AERCO BMK 3.0 LN Nat. Gas Jan 2009 User Manual Gas Jan 2009

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Page 1

Instruction

GF-116

AERCO INTERNATIONAL, Inc., Northvale, New Jersey, 07647 USA

No.

Installation, Operation

& Maintenance Instructions

Benchmark 3.0LN Series Gas Fired Low NOx Boiler System

Condensing, Modulating

Forced Draft, Hot Water Boiler

3,000,000 BTU/H Input

Applicable for Serial Numbers G-06-1069 and above

Printed in U.S.A. REVISED JANUARY, 2009

Page 2

Telephone Support

Direct to AERCO Technical Support (8 to 5 pm EST, Monday through Friday):

1-800-526-0288

AERCO International, Inc. 159 Paris Avenue Northvale, NJ 07647-0128

www.aerco,com

The information contained in this installation, operation and maintenance manual is subject to change without notice from AERCO International, Inc.

AERCO makes no warranty of any kind with respect to this material, including but not limited to implied warranties of merchantability and fitness for a particular application. AERCO International is not liable for errors appearing in this manual. Nor for incidental or consequential damages occurring in connection with the furnishing, performance, or use of this material.

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CONTENTS

GF-116 - AERCO BENCHMARK 3.0LN GAS FIRED LOW NOx BOILER

Operating & Maintenance Instructions

FOREWORD A

Chapter 1 – SAFETY PRECAUTIONS 1-1

Para. Subject Page

1-1 Warnings & Cautions 1-1 1-2 Emergency Shutdown 1-2

Chapter 2 – INSTALLATION 2-1

Para. Subject Page

2.1 Introduction 2-1

2.2 Receiving the Unit 2-1

2.3 Unpacking 2-1

2.4 Site Preparation 2-1

2.5 Supply and Return Piping 2-3

2.6 Condensate Drains 2-3

2.7 Gas Supply Piping 2-5

2.8 AC Electrical Power Wiring 2-6

Para. Subject Page

1-3 Prolonged Shutdown 1-2

Para. Subject Page

2.9 Modes of Operation and Field Control Wiring

2.10 I/O Box Connections 2-8

2.11 Auxiliary Relay Contacts 2-10

2.12 Flue Gas Vent Installation 2-10

2.13 Combustion Air 2-10

2-7

Chapter 3 – CONTROL PANEL COMPONENTS AND OPERATING PROCEDURES 3-1

Para. Subject Page

3.1 Introduction 3-1

3.2 Control Panel Description 3-1

3.3 Control Panel Menus 3-4

3.4 Operating Menu 3-5

3.5 Setup Menu 3-5

Para. Subject Page

3.6 Configuration Menu 3-6

3.7 Tuning Menu 3-7

3.8 Start Sequence 3-7

3.9 Start/Stop Levels 3-9

Chapter 4 – INITIAL START-UP 4-1

Para. Subject Page

4.1 Initial Startup Requirements 4-1

4.2 Tools and Instruments for Combustion Calibration

4.3 Natural Gas Combustion Calibration

4-1

4-2

Para. Subject Page

4.4 Unit Reassembly 4-5

4.5 Over-Temperature Limit Switch 4-5

Page 4

CONTENTS

Chapter 5 – MODE OF OPERATION 5-1

Para. Subject Page

5.1 Introduction 5-1

5.2 Indoor/Outdoor Reset Mode 5-1

5.3 Constant Setpoint Mode 5-2

5.4 Remote Setpoint Mode 5-2

5.5 Direct Drive Modes 5-3

Para. Subject Page

5.6 Boiler Management System (BMS)

5.7 Combination Control System (CCS)

5-4

5-5

Chapter 6 – SAFETY DEVICE TESTING PROCEDURES 6-1

Para. Subject Page

6.1 Testing of Safety Devices 6-1

6.2 Low Gas Pressure Fault Test 6-1

6.3 High Gas Pressure Test 6-2

6.4 Low Water Level Fault Test 6-2

6.5 Water Temperature Fault Test 6-2

6.6 Interlock Tests 6-3

6.7 Flame Fault Test 6-3

Para. Subject Page

6.8 Air Flow Fault Test 6-4

6.9 SSOV Proof of Closure Switch 6-4

6.10 Purge Switch Open During Purge

6.11 Ignition Switch Open During Ignition

6.12 Safety Pressure Relief Valve Test

6-5

6-6

Chapter 7 – MAINTENANCE REQUIREMENTS 7-1

Para. Subject Page

7.1 Maintenance Schedule 7-1

7.2 Spark Ignitor 7-1

7.3 Flame Detector 7-2

7.4 Combustion Calibration 7-2

7.5 Safety Device Testing 7-3

7.6 Burner 7-3

Para. Subject Page

7.7 Condensate Drain Trap 7-4

7.8 Shutting the Boiler Down For An Extended Period of Time

7.9 Placing The Boiler Back In Service After A Prolonged Shutdown

7-5

Chapter 8 – TROUBLESHOOTING GUIDE 8-1

Para. Subject Page

8.1 Introduction 8-1

Para. Subject Page

Page 5

CONTENTS

APPENDICES

App Subject Page

A Boiler Menu Item Descriptions A-1 B Startup, Status and Fault

Messages

C Temperature Sensor Resistance

Chart

D Indoor/Outdoor Reset Ratio

Charts E Boiler Default Settings E-1 F Dimensional and Part Drawings F-1

B-1

C-1

D-1

WARRANTIES W-1

App Subject Page

G Piping Drawings G-1 H Wiring Schematics H-1

I Recommended Periodic Testing

Checklist

J Benchmark Control Panel Views J-1

K Natural Gas Combustion

Calibration Procedure for Unit Serial Nos. Below G-07-1901

I-1

K-1

iii

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FOREWORD

Foreword

The AERCO Benchmark 3.0LN Boiler is a modulating unit. It represents a true industry advance that meets the needs of today's energy and environmental concerns. Designed for application in any closed loop hydronic system, the Benchmark's modulating capability relates energy input directly to fluctuating system loads. The Benchmark 3.0, with its 15:1 turn down ratio and condensing capability, provides extremely high efficiencies and makes it ideally suited for modern low temperature, as well as, conventional heating systems.

The Benchmark 3.0 operates at inputs ranging from 200,000 BTU/hr. to 3,000,000 BTU/hr. The output of the boiler is a function of the unit’s firing rate and return water temperature. Output ranges from 198,000 BTU/hr. to 2,900,000 BTU/hr., depending on operating conditions.

When installed and operated in accordance with this Instruction Manual, the Benchmark 3.0 Boiler complies with the NOx emission standards outlined in:

• South Coast Air Quality Management District (SCAQMD), Rule 1146.1

Whether used in singular or modular arrangements, the Benchmark 3.0 offers the maximum flexibility in venting with minimum installation space requirements. The Benchmark's advanced electronics are available in several selectable modes of operation offering the most efficient operating methods and energy management system integration.

For service or parts, contact your local sales representative or AERCO INTERNATIONAL.

NAME:

ORGANIZATION:

ADDRESS:

TELEPHONE:

INSTALLATION DATE: _____________________________________________

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SAFETY PRECAUTIONS

CHAPTER 1 SAFETY PRECAUTIONS

1.1 WARNINGS & CAUTIONS

Installers and operating personnel MUST, at all times, observe all safety regulations. The following warnings and cautions are general and must be given the same attention as specific precautions included in these instructions. In addition to all the requirements included in this AERCO Instruction Manual, the installation of units MUST conform with local building codes, or, in the absence of local codes, ANSI Z223.1 (National Fuel Gas Code Publication No. NFPA-

54). Where ASME CSD-1 is required by local jurisdiction, the installation must conform to CSD-1.

Where applicable, the equipment shall be installed in accordance with the current Installation Code for Gas Burning Appliances and Equipment, CGA B149, and applicable Provincial regulations for the class; which should be carefully followed in all cases. Authorities having jurisdiction should be consulted before installations are made.

IMPORTANT

This Instruction Manual is an integral part of the product and must be maintained in legible condition. It must be given to the user by the installer and kept in a safe place for future reference.

WARNINGS!

MUST BE OBSERVED TO PREVENT SERIOUS INJURY.

WARNING!

BEFORE ATTEMPTING TO PERFORM ANY MAINTENANCE ON THE UNIT, SHUT OFF ALL GAS AND ELECTRICAL INPUTS TO THE UNIT.

WARNING

DO NOT USE MATCHES, CANDLES, FLAMES, OR OTHER SOURCES OF IGNITION TO CHECK FOR GAS LEAKS.

WARNING!

FLUIDS UNDER PRESSURE MAY CAUSE INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT WHEN RELEASED. BE SURE TO SHUT OFF ALL INCOMING AND OUTGOING WATER SHUTOFF VALVES. CAREFULLY DECREASE ALL TRAPPED PRESSURES TO ZERO BEFORE PERFORMING MAINTENANCE.

WARNING!

ELECTRICAL VOLTAGES UP TO 460 VAC MAY BE USED IN THIS EQUIPMENT. THEREFORE THE COVER ON THE UNIT’S POWER BOX (LOCATED BEHIND THE FRONT PANEL DOOR) MUST BE INSTALLED AT ALL TIMES, EXCEPT DURING MAINTENANCE AND SERVICING.

CAUTIONS!

Must be observed to prevent equipment damage or loss of operating effectiveness.

CAUTION!

Many soaps used for gas pipe leak testing are corrosive to metals. The piping must clean water after leak checks have been completed.

be rinsed thoroughly with

WARNING!

THE EXHAUST VENT PIPE OF THE UNIT OPERATES UNDER A POSITIVE PRESSURE AND THEREFORE MUST BE COMPLETELY SEALED TO PREVENT LEAKAGE OF COMBUSTION PRODUCTS INTO LIVING SPACES.

CAUTION!

DO NOT use this boiler if any part has been under water. Call a qualified service technician to inspect and replace any part that has been under water.

1-1

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SAFETY PRECAUTIONS

1.2 EMERGENCY SHUTDOWN

If overheating occurs or the gas supply fails to shut off, close the manual gas shutoff valve (Figure 1-1) located external to the unit.

IMPORTANT

The Installer must identify and indicate the location of the emergency shutdown manual gas valve to operating personnel.

1.3 PROLONGED SHUTDOWN

After prolonged shutdown, it is recommended that the startup procedures in Chapter 4 and the safety device test procedures in Chapter 6 of this manual be performed, to verify all systemoperating parameters. If there is an emergency, turn off the electrical power supply to the AERCO boiler and close the manual gas valve located upstream the unit. The installer is to identify the emergency shut-off device.

Figure 1-1

Manual Gas Shutoff Valve

1-2

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INSTALLATION

CHAPTER 2 INSTALLATION

2.1 INTRODUCTION

This Chapter provides the descriptions and procedures necessary to unpack, inspect and install the AERCO Benchmark 3.0 Boiler. Brief descriptions are also provided for each available mode of operation. Detailed procedures for implementing these modes are provided in Chapter 5.

2.2 RECEIVING THE UNIT

Each Benchmark 3.0 System is shipped as a single crated unit. The shipping weight is approximately 2,170 pounds. The unit must be moved with the proper rigging equipment for safety and to avoid equipment damage. The unit should be completely inspected for evidence of shipping damage and shipment completeness at the time of receipt from the carrier and before the bill of lading is signed.

NOTE

AERCO is not responsible for lost or damaged freight.

Each unit has a Tip-N-Tell indicator on the outside of the crate. This indicates if the unit has been turned on its side during shipment. If the Tip-N-Tell indicator is tripped, do not sign for the shipment. Note the information on the carrier’s paperwork and request a freight claim and inspection by a claims adjuster before proceeding. Any other visual damage to the packaging materials should also be made clear to the delivering carrier.

2.3 UNPACKING

Carefully unpack the unit taking care not to damage the unit enclosure when cutting away packaging materials

• Pressure/Temperature Gauge

• Spare Spark Igniter

• Spare Flame Detector

• ASME Pressure Relief Valve

• Condensate Drain Trap

• 2” Gas Supply Shutoff Valve

When ordered, optional accessories may be packed separately, packed within the boiler shipping container, or may be installed on the boiler. Any standard or optional accessories shipped loose should be identified and stored in a safe place until ready for installation or use.

2.4 SITE PREPARATION.

Ensure that the site selected for installation of the Benchmark 3.0 Boiler includes:

• Access to AC Input Power corresponding to the ordered power configuration. The available power configurations are:

• 208 VAC, 3-Phase, 60 Hz @ 20 A

• 460 VAC, 3-Phase, 60 Hz @ 15 A

• Access to Natural Gas line at a static

pressure between 4 and 10 inches W.C.

2.4.1 Installation Clearances

The unit must be installed with the prescribed clearances for service as shown in Figure 2-1. The minimum AERCO, are listed below. However, if Local Building Codes require additional clearances, these codes shall supersede AERCO’s requirements. Minimum acceptable clearances required are:

• Sides: 24 inches

clearance dimensions, required by

A close inspection of the unit should be made to ensure that there is no evidence of damage not indicated by the Tip-N-Tell indicator. The freight carrier should be notified immediately if any damage is detected.

The following accessories come standard with each unit and are either packed separately within the unit’s packing container or are factory installed on the boiler:

• Front : 24 inches

• Rear: 43 inches

• Top: 18 inches

All gas piping, water piping and electrical conduit or cable must be arranged so that they do not interfere with the removal of any panels, or inhibit service or maintenance of the unit.

2-1

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INSTALLATION

Figure 2-1 Benchmark 3.0 Boiler Clearances

WARNING

KEEP THE UNIT AREA CLEAR AND FREE FROM ALL COMBUSTIBLE MATERIALS AND FLAMMABLE VAPORS OR LIQUIDS

CAUTION

While packaged in the shipping container, the boiler must be moved by pallet jack or forklift from the FRONT ONLY.

2.4.2 Setting the Unit

The unit must be installed on a 4 inch to 6 inch housekeeping pad to ensure proper condensate drainage. If anchoring the unit, refer to the dimensional drawings in Appendix F for anchor locations. A total of 3 lifting tabs are provided at the top of the primary heat exchanger as shown in Figure 2-2. However, USE ONLY TABS 1 AND 2 SHOWN IN FIGURE 2-2 TO MOVE THE ENTIRE UNIT. Tabs 1 and 3 are used only when removing or replacing the unit’s primary heat exchanger. Remove the front top panel from the unit to provide access to the lifting tabs. Remove the four (4) lag screws securing the unit to the shipping skid. Lift the unit off the shipping skid and position it on the 4 inch to 6 inch housekeeping concrete pad (required) in the desired location.

Figure 2-2

Lifting Lug Locations

In multiple unit installations, it is important to plan the position of each unit in advance. Sufficient space for piping connections and future service/maintenance requirements must also be taken into consideration. All piping must include ample provisions for expansion.

If installing a Combination Control Panel (CCP) system, it is important to identify the Combination Mode Boilers in advance and place them in the proper physical location. Refer to Chapter 5 for information on Combination Mode Boilers.

2-2

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2.4.3 Removal of Support Rod

Prior to installation of water supply and return piping, the 24” threaded rod shown in Figure 2-3 must be removed. This rod is installed prior to shipment from the factory to prevent damage to the insulated metal flex hose on the hot water supply outlet of the boiler. In order to install the water supply piping, this rod must be removed as follows:

1. Refer to Figure 2-3 and back off the hex nut on the outlet side of the flex hose.

2. Next, disconnect the coupling nut from the flange stud.

3. Completely remove the threaded rod, hex nut and coupling nut from the boiler.

5/8-11 x 24" LONG

THREADED ROD

OUTLET FLANGE

5/8-11

HEX NUT

8-11

COUPLING NUT

INSTALLATION

Figure 2-4

Supply and Return Locations

(SEE IMPORTANT

NOTE BELOW)

EXHAUST

MANIFOLD

PARTIAL TOP VIEW - REAR

Figure 2-3

Location of Threaded Support Rod

IMPORTANT

THE INSULATED FLEX HOSE SHOWN IN FIGURE 2-3 MUST LEVEL OR SLOPING UPWARD AS IT EXITS THE BOILER. FAILURE TO PROPERLY POSITION THIS HOSE MAY CAUSE INEFFECTIVE AIR ELIMINATION RESULTING IN ELEVATED TEMPERATURES THAT COULD COMPROMISE THE TOP HEAD GASKET.

2.5 SUPPLY AND RETURN PIPING

The Benchmark 3.0 Boiler utilizes 4” 150# flanges for the water system supply and return piping connections. The physical location of the supply and return piping connections are on the rear of the unit as shown in Figure 2-4. Refer to Appendix F, Drawing AP-A-811 for additional dimensional data.

2.6 CONDENSATE DRAINS

The Benchmark 3.0 Boiler is designed to condense water vapor from the flue products. Therefore, the installation must have provisions for suitable condensate drainage or collection.

Two condensate drain connections are provided on the rear of the unit as shown in Figure 2-5. One drain connection is located on the exhaust manifold and the other is located on the connecting manifold.

The drain at the bottom of the exhaust manifold also includes a condensate trap containing a float assembly. When condensate collects in the exhaust manifold, the float rises, thereby allowing it to discharge through the drain opening. The drain pipe located on the connecting manifold must be connected to a second condensate trap which is packed separately within the unit’s shipping container.

The procedures to install and connect both of the condensate drains are provided in paragraphs 2.6.1 and 2.6.2.

2-3

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INSTALLATION

EXHAUST

MANIFOLD

CONDENSATE

TRAP

DRAIN

NOTE

The condensate trap described in the following steps can be installed on the

floor behind the unit as shown in Figure 2-

6. There will be sufficient downward slope from the drain pipe to the trap inlet to drain the condensate by gravity. Ensure that the outlet hose from the trap slopes away (down) from the trap.

SHELL DRAIN

VALVE

CONNECTING

MANIFOLD

EXHAUST

MANIFOLD

CONDENSATE

TRAP

DRAIN

HOSE

CLAMP

1" I.D.

HOSE

VIEW “A - A”

DRAIN

UNIT

FRAME

TO FLOOR

DRAIN

REAR VIEW

DRAIN

VALVE

CONNECTING

CONDENSATE

DRAIN PIPE

UNIT

FRAME

SHELL

MANIFOLD

TRAP

VIEW “B - B”

Figure 2-5

Condensate Drain Connection Location

2.6.1 Exhaust Manifold Condensate

Drain

Refer to Figure 2-5, View A – A and install as follows:

1. Position the supplied condensate trap (part no. 24060) on the floor at the rear of the unit.

2. Install 3/4” NPT nipples in the tapped inlet and outlet of the condensate trap.

3. Attach a length of 1½” I.D (part no. GM-

123352). hose between the connecting manifold drain pipe and the inlet side of the condensate trap (Figure 2-6). Secure both ends of the hose with clamps.

4. Connect a second length of 1” I.D. polypropylene hose to the outlet side of the condensate trap and route it to a nearby floor drain.

If desired, a Tee fitting may be used to connect the two drain hoses from the exhaust manifold and the outlet side

of the of the condensate trap connected

If a floor drain is not available, a condensate pump can be used to remove the condensate to drain. The maximum condensate flow rate is 20 GPH. The condensate drain trap, associated fittings and drain lines must be removable for routine maintenance. Therefore, DO NOT hard pipe.

1. Connect a length of 1 inch I.D. hose (part no.

91030) to the drain on the connecting manifold and secure it in place with a hose clamp.

2. Route the hose to a nearby floor drain.

2.6.2 Connecting Manifold Condensate Drain

The connecting manifold drain pipe shown in Figure 2-5, View B – B must be connected to a separate condensate drain trap external to the unit. Refer to Figure 2-6 and install the trap as follows:

2-4

Figure 2-6

Condensate Trap Installation

Page 15

INSTALLATION

2.7 GAS SUPPLY PIPING

The AERCO Benchmark 3.0 Gas Components and Supply Design Guide, GF-3030 must be consulted prior to designing or installing any gas supply piping.

WARNING

NEVER USE MATCHES, CANDLES, FLAMES OR OTHER SOURCES OF IGNITION TO CHECK FOR GAS LEAKS

Many soaps used for gas pipe leak testing are corrosive to metals. Therefore, piping must be rinsed thoroughly with clean water after leak checks have been completed.

All gas piping must be arranged so that it does not interfere with removal of any covers, inhibit service/maintenance, or restrict access between the unit and walls, or another unit.

CAUTION

NOTE

2.7.1 Gas Supply Specification

The gas supply input specifications to the unit for Natural Gas are as follows:

The maximum static pressure to the unit must not exceed 2 psi. The minimum operating gas pressure for natural gas is 4 inches W.C. for both FM and IRI gas trains when the unit is firing at maximum input. The gas supply pressure to the unit must be of sufficient capacity to provide 3000 cfh while maintaining the gas pressure at 4 inches W.C. for FM or IRI gas trains.

2.7.2 Manual Gas Shutoff Valve

A manual shut-off valve must be installed in the gas supply line upstream of the Boiler as shown in Figure 2-7. Maximum allowable gas pressure to the Boiler is 2 psi

A 2 inch gas inlet connection is located on the rear of the unit as shown in Figure 2-4.

Prior to installation, all pipes should be deburred and internally cleared of any scale, metal chips or other foreign particles. Do Not install any flexible connectors or unapproved gas fittings. Piping must be supported from the floor, ceiling or walls only and must not be supported by the unit.

A suitable piping compound, approved for use with natural gas, should be used. Any excess must be wiped off to prevent clogging of components.

To avoid unit damage when pressure testing gas piping, isolate the unit from the gas supply piping. At no time should the gas pressure applied to the unit exceed 2 psi. Leak test all external piping thoroughly using a soap and water solution or suitable equivalent. The gas piping used must meet all applicable codes.

Figure 2-7

Manual Gas Shut-Off Valve Location

2-5

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INSTALLATION

2.7.3 IRI Gas Train Kit

The IRI gas train is an optional gas train configuration which is required in some areas for code compliance or for insurance purposes. The IRI gas train is factory pre-piped and wired. See Appendix F, Drawing AP-A-803 for details.

2.8 AC ELECTRICAL POWER WIRING

The AERCO Benchmark 3.0 Electrical Power Wiring Guide, GF-3060, must be consulted prior to connecting any AC power wiring to the unit. External AC power connections are made to the unit inside the Power Box on the front panel of the unit. Remove the front door of the unit to access the Power Box mounted directly above the Control Box. Loosen the four Power Box cover screws and remove cover to access the AC terminal connections inside the Power Box (Figure 2-8).

NOTE

All electrical conduit and hardware must be installed so that it does not interfere with the removal of any unit covers, inhibit service/maintenance, or prevent access between the unit and walls or another unit.

2.8.1 Electrical Power Requirements

The AERCO Benchmark 3.0 Boiler is available in two different AC power configurations:

• 208 VAC/3-Phase/60 @20 amps

• 460 VAC/3-Phase/60 Hz @ 15 amps

Each of the power configurations utilize a Power Box with a terminal block that matches the configuration ordered. The two different terminal block configurations are shown in Figure 2-9. A wiring diagram showing the required AC power connections is provided on the front cover of the Power Box.

Each Benchmark 3.0 Boiler must be connected to a dedicated electrical circuit. NO OTHER DEVICES SHOULD BE ON THE SAME ELECTRICAL CIRCUIT AS THE BENCHMARK BOILER. A means for disconnecting AC power from the unit (such as a service switch) must be installed near the unit for normal operation and maintenance. All electrical connections should be made in accordance with the National Electrical Code and/or with any applicable local codes.

For electrical power wiring diagrams, see the AERCO Benchmark 3.0 Electrical Power Wiring Guide, (GF-3060).

Figure 2-8

AC Input Terminal Block Location

Figure 2-9

AC Terminal Block Configurations

2-6

Page 17

2.9 MODES OF OPERATION AND FIELD CONTROL WIRING

The Benchmark 3.0 Boiler is available in several different modes of operation. While each unit is factory configured and wired for its intended mode, some additional field wiring may be required to complete the installation. This wiring is typically connected to the Input/Output (I/O) Box located on the lower portion of the unit front panel (Figure 2-10) behind the removable front door.

To access the I/O Box terminal strips shown in Figure 2-10, loosen the four cover screws and remove the cover. All field wiring is installed from the rear of the panel by routing the wires through one of the four bushings provided.

Refer to the wiring diagram provided on the cover of the I/O Box (Figure 2-11) when making all wiring connections.

In addition to the terminal strips shown in Figure 2-10, the I/O Box also contains a pre-wired temperature transmitter which receives inlet air temperature sensor readings and transmits this signal to the variable frequency drive (VFD) contained in the Benchmark 3.0 Boiler. The VFD utilizes this input signal to adjust the rotation speed of the blower.

INSTALLATION

Figure 2-10.

Input/Output (I/O) Box Location

Brief descriptions of each mode of operation, and their wiring requirements, are provided in the following paragraphs. Additional information concerning field wiring is provided in paragraphs

2.9.1 through 2.9.9. Refer to Chapter 5 for

detailed information on the available modes of operation.

Figure 2-11. I/O Box Terminal Strip

2-7

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INSTALLATION

2.9.1 Constant Setpoint Mode

The Constant Setpoint Mode is used when it is desired to have a fixed setpoint that does not deviate. No wiring connections, other than AC electrical power connections, are required for this mode. However, if desired, fault monitoring or enable/disable interlock wiring can be utilized (see paragraphs 2.9.9.1 and 2.9.10).

2.9.2 Indoor/Outdoor Reset Mode

This mode of operation increases supply water temperature as outdoor temperatures decrease. An outside air temperature sensor (AERCO Part No. 122790) is required. The sensor MUST BE wired to the I/O Box wiring terminals (see Figure 2-11). Refer to paragraph 2.10.1 for additional information on outside air temperature sensor installation.

2.9.3 Boiler Management System Mode

NOTE

BMS Model 168 can utilize either pulse width modulation (PWM) or RS485 Modbus signaling to the Boiler. BMS II Model 5R5-384 can utilize only RS485 signaling to the Boiler.

When using an AERCO Boiler Management System (BMS), the field wiring is connected between the BMS Panel and each Boiler’s I/O Box terminal strip (Figure 2-11). Twisted shielded pair wire from 18 to 22 AWG must be utilized for the connections. The BMS Mode can utilize either pulse width modulation (PWM) signaling, or RS485 Modbus signaling. For PWM signaling, connections are made from the AERCO Boiler Management System to the B.M.S. (PWM) IN terminals on the I/O Box terminal strip. For RS485 Modus signaling, connections are made from the BMS to the RS485 COMM terminals on the I/O Box terminal strip. Polarity must be maintained and the shield must be connected only at the AERCO BMS. The boiler end of the shield must be left floating. For additional instructions, refer to Chapter 5, paragraph 5.6 in this manual. Also, refer to GF108M (BMS Model 168) and GF-124 (BMS II Model 5R5-384), BMS -Operations Guides.

2.9.4 Remote Setpoint and Direct Drive Modes

The Benchmark 3.0 Boiler can accept several types of signal formats from an Energy Management System (EMS), Building Automation System (BAS) or other source, to control either the setpoint (Remote Setpoint

Mode) or firing rate (Direct Drive Mode) of the Boiler. These formats are:

• 4 to 20 mA/1 to 5 VDC

• 0 to 20 mA/0 to 5 VDC

• PWM – (Pulse Width Modulated signal. See

para. 2.10.4)

• Network (RS485 Modbus. See para. 2.10.7)

While it is possible to control a boiler or boilers using one of the previously described modes of operation, it may not be the method best suited for the application. Prior to selecting one of these modes of operation, it is recommended that you consult with your local AERCO representative or the factory for the mode of operation that will work best with your application. For more information on wiring the 4 to 20 mA / 1to 5VDC or the 0 to 20 mA / 0 to 5 VDC, see paragraph 2.9.3.

2.9.5 Combination Mode

NOTE

Only BMS Model 168 can be utilized for the Combination Mode, not the BMS II (Model 5R5-384).

With a Combination Mode unit, field wiring is between the unit’s I/O Box wiring terminals, the CCP (Combination Control Panel), and the BMS Model 168 (Boiler Management System). The wiring must be accomplished using twistedshielded pair wire from 18 to 22 AWG. Polarity must be maintained. For further instructions and wiring diagrams, refer to the GF-108 Boiler Management System Operations Guide and the CCP-1 data sheet.

2.10 I/O BOX CONNECTIONS

The types of input and output signals and devices to be connected to the I/O Box terminals shown in Figure 2-11 are described in the following paragraphs.

CAUTION

DO NOT make any connections to the I/O Box terminals labeled “NOT USED”. Attempting to do so may cause equipment damage.

2.10.1 OUTDOOR SENSOR IN

An outdoor air temperature sensor (AERCO Part No. 122790) will be required primarily for the Indoor/Outdoor reset mode of operation. It can also be used with another mode if it is desired to use the outdoor sensor enable/disable feature. This feature allows the boiler to be enabled or disabled based on the outdoor air temperature.

2-8

Page 19

INSTALLATION

The factory default for the outdoor sensor is DISABLED. To enable the sensor and/or select an enable/disable outdoor temperature, see the Configuration menu in Chapter 3.

The outdoor sensor may be wired up to 200 feet from the boiler. It is connected to the OUTDOOR SENSOR IN and SENSOR COMMON terminals in the I/O Box (see Figures 2-10 and 2-11). Wire the sensor using a twisted shielded pair wire from 18 to 22 AWG. There is no polarity to observe when terminating these wires. The shield is to be connected only to the terminals labeled SHIELD in the I/O Box. The sensor end of the shield must be left free and ungrounded.

When mounting the sensor, it must be located on the North side of the building where an average outside air temperature is expected. The sensor must be shielded from direct sunlight as well as impingement by the elements. If a shield is used, it must allow for free air circulation.

2.10.2 AUX SENSOR IN

The AUX SENSOR IN terminals can be used to add an additional temperature sensor for monitoring purposes. This input is always enabled and is a view-only input that can be seen in the Operating Menu. The sensor must be wired to the AUX SENSOR IN and SENSOR COMMON terminals and must be similar to AERCO BALCO wire sensor Part No. 12449. A resistance chart for this sensor is provided in Appendix C.

2-11). Polarity must be maintained. The shield must be connected only at the source end and must be left floating (not connected) at the Boiler’s I/O Box.

Regardless of whether voltage or current is used for the drive signal, they are linearly mapped to a 40°F to 240°F setpoint or a 0% to 100% firing rate. No scaling for these signals is provided

2.10.4 B.M.S. (PWM) IN

NOTE

Only BMS Model 168 can utilize Pulse Width Modulation (PWM), not the BMS II (Model 5R5-384).

These terminals are used to connect the AERCO Boiler Management System (BMS) Model 168 to the unit. The BMS Model 168 utilizes a 12 millisecond, ON/OFF duty cycle. This duty cycle is Pulse Width Modulated (PWM) to control firing rate. A 0% firing rate = a 5% ON pulse and a 100% firing rate = a 95% ON pulse.

2.10.5 SHIELD

The SHIELD terminals are used to terminate any shields used on sensor wires connected to the unit. Only shields must be connected to these terminals.

2.10.6 mA OUT

These terminals provide a 4 to 20 mA output to the VFD to control the rotational speed of the blower. This function is enabled in the Configuration Menu (Chapter 3, Table 3.4).

2.10.3 ANALOG IN

The ANALOG IN + and – terminals are used when an external signal is used to drive the firing rate (Direct Drive Mode) or change the setpoint (Remote Setpoint Mode) of the Boiler.

Either a 4 to 20 mA /1 to 5 VDC or a 0 to 20 mA / 0 to 5 VDC signal may be used to vary the setpoint or firing rate. The factory default setting is for 4 to 20 mA / 1 to 5 VDC, however this may be changed to 0 to 20 mA / 0 to 5 VDC using the Configuration Menu described in Chapter 3. If voltage rather than current is selected as the drive signal, a DIP switch must be set on the PMC Board located inside the Control Box. Contact the AERCO factory for information on setting DIP switches.

All of the supplied signals must be floating (ungrounded) signals. Connections between the signal source and the Boiler’s I/O Box must be made using twisted shielded pair wire from 18 to 22 AWG, such as Belden 9841 (see Figure

2.10.7 RS-485 COMM

These terminals are used for RS-485 MODBUS serial communication between the unit and an external “Master” such as a Boiler Management System (BMS), Energy Management System (EMS), Building Automation System (BAS) or other suitable device.

2.10.8 EXHAUST SWITCH IN

These terminals permit an external exhaust switch to be connected to the exhaust manifold of the boiler. The exhaust switch should be a normally open type switch (such as AERCO Part No. 123463) that closes (trips) at 500°F.

2.10.9 INTERLOCKS

The unit offers two interlock circuits for interfacing with Energy Management Systems and auxiliary equipment such as pumps or louvers. These interlocks are called the Remote Interlock and Delayed Interlock (Figure 2-11). The wiring terminals for these interlocks are

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INSTALLATION

located inside the I/O Box on the unit front panel. The I/O Box cover contains a wiring diagram which shows the terminal strip locations for these interlocks (REMOTE INTL’K IN and DELAYED INTL’K IN). Both interlocks, described below, are factory wired in the closed position.

NOTE

Both the Delayed Interlock and Remote Interlock MUST be in the closed position to allow the unit to fire.

2.10.9.1 REMOTE INTERLOCK IN

The remote interlock circuit is provided to remotely start (enable) and stop (disable) the Boiler, if desired. The circuit is labeled REMOTE INTL’K IN and is located inside the I/O Box on the front panel. The circuit is 24 VAC and is factory pre-wired in the closed (jumpered) position.

2.10.9.2 DELAYED INTERLOCK IN

The delayed interlock is typically used in conjunction with the auxiliary relay described in paragraph 2.10. This interlock circuit is located in the purge section of the start string. It can be connected to the proving device (end switch, flow switch etc.) of an auxiliary piece of equipment started by the Boiler’s auxiliary relay. The delayed interlock must be closed for the boiler to fire.

If the delayed interlock is connected to a proving device that requires time to close (make), a time delay (Aux Start On Dly) that holds the start sequence of the boiler long enough for a proving switch to make can be programmed. Should the proving switch not prove within the programmed time frame, the boiler will shut down. The Aux Start On Dly can be programmed from 0 to 120 seconds. This option is locate in the Configuration Menu (Chapter 3, Table 3-4).

2.10.10 FAULT RELAY

The fault relay is a single pole double throw (SPDT) relay having a normally open and normally closed set of relay contacts that are rated for 5 amps at 120 VAC and 5 amps at 30 VDC. The relay energizes when any fault condition occurs and remains energized until the fault is cleared and the CLEAR button is depressed. The fault relay connections are shown in Figure 2-11.

2.11 AUXILIARY RELAY CONTACTS

Each Boiler is equipped with a single pole double throw (SPDT) relay that is energized when there is a demand for heat and deenergized after the demand for heat is satisfied. The relay is provided for the control of auxiliary equipment, such as pumps and louvers, or can be used as a Boiler status indictor (firing or not firing). Its contacts are rated for 120 VAC @ 5 amps. Refer to Figure 2-11 to locate the AUX RELAY terminals for wiring connections.

2.12 FLUE GAS VENT INSTALLATION

The minimum allowable vent diameter for a single Benchmark 3.0 Boiler is 8 inches.

The AERCO Benchmark Venting and Combustion Air Guide, GF-3050, must be consulted before any flue gas vent or inlet air venting is designed or installed. U/L listed, positive pressure, watertight vent materials as specified in AERCO’s GF-3050, must be used for safety and code compliance. Since the unit is capable of discharging low temperature exhaust gases, horizontal sections of the flue vent system must be pitched back to the unit a minimum of 1/4 inch per foot to avoid condensate pooling and allow for proper drainage.

The combined pressure drop of vent and combustion air systems must not exceed 140 equivalent feet of 8 inch ducting. Fittings as well as pipe lengths must be calculated as part of the equivalent length.

For a natural draft installation the draft must not exceed ±0.25 inch W.C. These factors must be planned into the vent installation. If the maximum allowable equivalent lengths of piping are exceeded, the unit will not operate properly or reliably.

2.13 COMBUSTION AIR

The AERCO Benchmark Venting and Combustion Air Guide, GF-3050 MUST be consulted before any flue or combustion supply air venting is designed or implemented. Combustion air supply is a direct requirement of ANSI 223.1, NFPA-54, and local codes. These codes should be consulted before a permanent design is determined.

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INSTALLATION

The combustion air must be free of chlorine, halogenated hydrocarbons, or other chemicals that can become hazardous when used in gasfired equipment. Common sources of these compounds are swimming pools, degreasing compounds, plastic processing and refrigerants. Whenever the environment contains these types of chemicals, combustion air must be supplied from a clean area outdoors for the protection and longevity of the equipment.

The AERCO Benchmark 3.0 Boiler is UL listed for 100% sealed combustion. It can also be installed using room air, provided there is an adequate supply. (See paragraph 2.13.3 for more information concerning sealed combustion air). If the sealed combustion air option is not being used, an inlet screen will be attached at the air inlet on the top of the unit

The more common methods of supplying combustion air are outlined below. For more information concerning combustion air, consult the AERCO Benchmark Venting and Combustion Air Guide, GF-3050.

2.13.1 Combustion Air From Outside the Building

Air supplied from outside the building must be provided through two permanent openings. Each opening must have a free area of not less than one square inch for each 4000 BTU/H boiler input. The free area must take into account restrictions such as louvers and bird screens.

2.13.2 Combustion Air From Inside The

Building

When combustion air is provided from within the building, it must be supplied through two permanent openings in an interior wall. Each opening must have a free area of not less than one square inch per 1000 BTU/H of total boiler input. The free area must take into account any restrictions such as louvers.

2.13.3 Sealed Combustion

The AERCO Benchmark 3.0 Boiler is UL listed for 100%-sealed combustion. For sealed combustion installations, the screen on the air inlet duct of the unit must be removed. The inlet air ductwork must then be attached directly to the unit’s air inlet.

In a sealed combustion air application, the combustion air ducting pressure losses must be taken into account when calculating the total maximum allowable venting run. See the AERCO Benchmark Venting and Combustion Air Guide, GF-3050. When using the boiler in a sealed combustion air configuration, each unit must have a minimum 8 inch diameter connection at the unit.

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CONTROL PANEL OPERATING PROCEDURES

CHAPTER 3 CONTROL PANEL OPERATING PROCEDURES

3.1 INTRODUCTION

The information in this Chapter provides a guide to the operation of the Benchmark 3.0 Boiler using the Control Panel mounted on the front of the unit. It is imperative that the initial startup of this unit be performed by factory trained personnel. Operation prior to initial startup by factory trained personnel will void the equipment warranty. In addition, the following WARNINGS and CAUTIONS must be observed at all times.

CAUTION

All of the installation procedures in Chapter 2 must be completed before attempting to start the unit.

WARNING

ELECTRICAL VOLTAGES IN THIS SYSTEM MAY INCLUDE 460, 208 AND 24 VOLTS AC. IT MUST BE SERVICED ONLY BY FACTORY CERTIFIED SERVICE TECHNICIANS

WARNING

DO NOT ATTEMPT TO DRY FIRE THE BOILER. STARTING THE UNIT WITHOUT A FULL WATER LEVEL CAN SERIOUSLY DAMAGE THE UNIT AND MAY RESULT IN INJURY TO PERSONNEL OR PROPERTY DAMAGE. THIS SITUATION WILL VOID ANY WARRANTY.

3.2 CONTROL PANEL DESCRIPTION

The Benchmark 3.0 Control Panel shown in Figure 3-1 contains all of the controls, indicators and displays necessary to operate, adjust and troubleshoot the Benchmark 3.0 Boiler. These operating controls, indicators and displays are listed and described in Table 3-1. Additional information on these items are provided in the individual operating procedures provided in this Chapter.

Figure 3-1.

Control Panel Front View

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CONTROL PANEL OPERATING PROCEDURES

Table 3-1 Operating Controls, Indicators and Displays

ITEM

NO.

CONTROL, INDICATOR

OR DISPLAY

1 LED Status Indicators Four Status LEDs indicate the current operating status as

follows:

COMM

MANUAL

REMOTE

DEMAND

OUTLET

TEMPERATURE Display

3 VFD Display Vacuum Fluorescent Display (VFD) consists of 2 lines each

Lights when RS-232 communication is occurring

Lights when the unit is being controlled using the front panel keypad.

Lights when the unit is being controlled by an external signal from an Energy Management System

Lights when there is a demand for heat.

3–Digit, 7–Segment LED display continuously displays the outlet water temperature. The °F or °C LED next to the display lights to indicate whether the displayed temperature is in degrees Fahrenheit or degrees Celsius.

capable of displaying up to 16 alphanumeric characters. The information displayed includes:

Startup Messages

Fault Messages

Operating Status Messages

FUNCTION

Menu Selection

RS-232 Port

FAULT Indicator Red FAULT LED indicator lights when a boiler alarm

CLEAR Key Turns off the FAULT indicator and clears the alarm message

READY Indicator

ON/OFF Switch

LOW WATER LEVEL

TEST/RESET Switches

Port permits a Laptop Computer or External Modem to be connected to the unit’s Control Panel.

condition occurs. An alarm message will appear in the VFD.

if the alarm is no longer valid. Lockout type alarms will be latched and cannot be cleared by simply pressing this key. Troubleshooting may be required to clear these types of alarms.

Lights ON/OFF switch is set to ON and all Pre-Purge conditions have been satisfied.

Enables and disables boiler operation.

Allows operator to test operation of the water level monitor.

Pressing TEST opens the water level probe circuit and simulates a Low Water Level alarm.

Pressing RESET resets the water level monitor circuit.

Pressing the CLEAR key (item 6) resets the display.

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CONTROL PANEL OPERATING PROCEDURES

Table 3-1 Operating Controls, Indicators and Displays – Continued

ITEM

NO.

10 MENU Keypad Consists of 6 keys which provide the following functions for

CONTROL, INDICATOR

OR DISPLAY

the Control Panel Menus:

BACK

▲ (UP) Arrow When in one of the main menu categories (Figure 3-2),

▼ (DOWN) Arrow When in one of the main menu categories (Figure 3-2),

CHANGE

Steps through the main menu categories shown in Figure 3-

2. The Menu categories wrap around in the order shown.

Allows you to go back to the previous menu level without changing any information. Continuously pressing this key will bring you back to the default status display in the VFD. Also, this key allows you to go back to the top of a main menu category.

pressing the ▲ arrow key will select the displayed menu category. If the CHANGE key was pressed and the menu item is flashing, pressing the ▲ arrow key will increment the selected setting.

pressing this key will select the displayed menu category. If the CHANGE key was pressed and the menu item is flashing, pressing the ▼ arrow key will decrement the selected setting.

Permits a setting to be changed (edited). When the CHANGE key is pressed, the displayed menu item will begin to flash. Pressing the ▲ or ▼ arrow key when the item is flashing will increment or decrement the displayed setting.

FUNCTION

ENTER

AUTO/MAN Switch

FIRE RATE Bargraph

Saves the modified menu settings in memory. The display will stop flashing.

This switch toggles the boiler between the Automatic and Manual modes of operation. When in the Manual (MAN) mode, the front panel controls are enabled and the MANUAL status LED lights.

When in the Automatic (AUTO) mode, the MANUAL status LED will be off and the front panel controls disabled.

20 segment red LED bargraph continuously shows the Fire Rate in 5% increments from 0 to 100%

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CONTROL PANEL OPERATING PROCEDURES

3.3 CONTROL PANEL MENUS

The Control Panel incorporates an extensive menu structure which permits the operator to set up, and configure the unit. The menu structure consists of four major menu categories as shown in Figure 3-2. Each of the menus shown, contain options which permit operating parameters to be viewed or changed. The menus are protected by a password to prevent unauthorized use.

Prior to entering the correct password, the options contained in the Operating, Setup, Configuration and Tuning Menu categories can be viewed. However, with the exception of Internal Setpoint Temperature (Configuration Menu), none of the viewable menu options can be changed.

Once the valid password (159) is entered, the options listed in the Setup. Configuration and Tuning Menus can be viewed and changed, if desired.

3.3.1 Menu Processing Procedure

Accessing and initiating each menu and option is accomplished using the Menu Keys shown in Figure 3-1. Therefore, it is imperative that you be thoroughly familiar with the following basic steps before attempting to perform specific menu procedures.

around after the first or last available option is reached.

6. To change the value or setting of a displayed menu option, press the CHANGE key. The displayed option will begin to flash. Press the ▲ or ▼ arrow key to scroll through the available menu option choices for the option to be changed. The menu option choices do not wrap around.

7. To select and store a changed menu item, press the ENTER key.

1. The Control Panel will normally be in the Operating Menu and the VFD will display the current unit status. Pressing the ▲ or ▼ arrow key will display the other available data items in the Operating Menu.

2. Press the MENU key. The display will show the Setup Menu, which is the next menu category shown in Figure 3-2. This menu contains the Password option which must be entered if other menu options will be changed.

3. Continue pressing the MENU key until the desired menu is displayed.

4. With the desired menu displayed, press the ▲ or ▼ arrow key. The first option in the selected menu will be displayed.

5. Continue to press the ▲ or ▼ arrow key until the desired menu option is displayed. Pressing the ▲ arrow key will display the available menu options in the Top-Down sequence. Pressing the ▼ arrow key will display the options in the Bottom-Up sequence. The menu options will wrap-

Figure 3-2. Menu Structure

NOTE

The following paragraphs provide brief descriptions of the options contained in each menu. Refer to Appendix A for detailed descriptions of each menu option. Refer to Appendix B for listings and descriptions of displayed startup, status and error messages.

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CONTROL PANEL OPERATING PROCEDURES

3.4 OPERATING MENU

The Operating Menu displays a number of key operating parameters for the unit as listed in Table 3-2. This menu is “Read-Only” and does not allow personnel to change or adjust any displayed items. Since this menu is “Read-Only”, it can be viewed at any time without entering a password. Pressing the ▲ arrow key to display the menu items in the order listed (Top-Down). Pressing the ▼ arrow key will display the menu items in reverse order (Bottom-Up).

3.5 SETUP MENU

The Setup Menu (Table 3-3) permits the operator to enter the unit password (159) which is required to change the menu options. To prevent unauthorized use, the password will

Table 3-2. Operating Menu

Available Choices or Limits

Menu Item Display Minimum Maximum Default

Status Message

time-out after 1 hour. Therefore, the correct password must be reentered when required. In addition to permitting password entries, the Setup Menu is also used to enter date and time, units of temperature measurements and entries required for external communication and control of the unit via the RS-232 port. A view-only software version display is also provided to indicate the current Control Box software version.

NOTE

The Outdoor Temp display item shown with an asterisk in Table 3-2 will not be displayed unless the Outdoor Sensor function has been enabled in the Configuration Menu (Table 3-4).

Active Setpoint 40°F 240°F

Aux Temp 30°F 245°F

Outdoor Temp* -70°F 130°F

Fire Rate In 0% Max Fire Rate

Flame Strength 0% 100%

Run Cycles 0 999,999

Run Hours 0 999,999

Fault Log 0 9 0

Table 3-3. Setup Menu

Available Choices or Limits

Menu Item Display Minimum Maximum Default

Passsword 0 9999 0

Language English English

Time 12:00 am 11:59 pm

Date 01/01/00 12/31/99

Unit of Temp Fahrenheit or Celsius Fahrenheit

Comm Address 0 127 0

Baud Rate 2400, 4800, 9600, 19.2K 9600

Software Ver 0.00 Ver 9.99

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CONTROL PANEL OPERATING PROCEDURES

3.6 CONFIGURATION MENU

The Configuration Menu shown in Table 3-4 permits adjustment of the Internal Setpoint (Setpt) temperature regardless of whether the valid password has been entered. Setpt is required for operation in the Constant Setpoint mode. The remaining options in this menu require the valid password to be entered, prior to changing existing entries. This menu contains a number of other configuration settings which may or may not be displayed, depending on the current operating mode setting.

Table 3-4. Configuration Menu

Available Choices or Limits

Menu Item Display Minimum Maximum Default

Internal Setpt Lo Temp Limit Hi Temp Limit 130°F

Unit Type Boiler or Water Heater Boiler

Unit Size 0.5 MBTU, 1.0 MBTU

1.5 MBTU, 2.0 MBTU

2.5 MBTU, 3.0 MBTU

Boiler Mode Constant Setpoint,

Remote Setpoint,

Combination

Outdoor Reset

NOTE

The Configuration Menu settings shown in Table 3-4 are Factory-Set in accordance with the requirements specified for each individual order. Therefore, under normal operating conditions, no changes will be required.

1.0 MBTU

Constant

Setpoint

Direct Drive

Remote Signal (If Mode = Remote Setpoint, Direct Drive or Combination)

Bldg Ref Temp (If Mode = Outdoor Reset)

Reset Ratio (If Mode = Outdoor Reset)

Outdoor Sensor Enabled or Disabled Disabled

System Start Tmp (If Outdoor Sensor = Enabled)

Setpt Lo Limit 40°F Setpt Hi Limit 60°F

Setpt Hi Limit Setpt Lo Limit 220°F 200°F

Temp Hi Limit 40°F 240°F 210°F

Max Fire Rate 40% 100% 100%

Pump Delay Timer 0 min. 30 min. 0 min.

Aux Start On Dly 0 sec. 120 sec. 0 sec.

4 – 20 mA/1 – 5V

0 -20 mA/0 – 5V

PWM Input (BMS)

Network

40°F 230°F 70°F

0.1 9.9 1.2

30°F 100°F 60°F

4 – 20 mA,

1-5V

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CONTROL PANEL OPERATING PROCEDURES

Table 3-4. Configuration Menu - Continued

Available Choices or Limits

Menu Item Display Minimum Maximum Default

Failsafe Mode Shutdown or Constant Setpt Shutdown

*mA Output (See CAUTION)

Low Fire Timer 2 sec. 120 sec. 2 sec.

Setpt Limiting Enabled or Disabled Disabled

Setpt Limit Band 0°F 10°F 5°F

*CAUTION: DO NOT CHANGE mA Output Menu Itemfrom its Default setting.

Setpoint, Outlet Temp,

Fire Rate Out, Off

*Fire Rate

Out

3.7 TUNING MENU

The Tuning Menu items in Table 3-5 are Factory set for each individual unit. Do not change

these menu entries unless specifically requested to do so by Factory-Trained personnel.

Table 3-5. Tuning Menu

Available Choices or Limits

Menu Item Display Minimum Maximum Default

Prop Band 1°F 120°F 70°F

Integral Gain 0.00 2.00 1.00

Derivative Time 0.0 min 2.00 min 0.00 min

Reset Defaults? Yes

Are You Sure?

3.8 START SEQUENCE

When the Control Box ON/OFF switch is set to the ON position, it checks all pre-purge safety switches to ensure they are closed. These switches include:

• Safety Shut-Off Valve Proof of Closure

(POC) switch

• Low Water Level switch

• High Water Temperature switch

• High Gas Pressure switch

• Low Gas Pressure switch

• Blower Proof switch

If all of the above switches are closed, the READY light above the ON/OFF switch will light and the unit will be in the Standby mode.

When there is a demand for heat, the following events will occur:

NOTE

If any of the Pre-Purge safety device switches are open, the appropriate fault message will be displayed. Also, the appropriate fault messages will be displayed throughout the start sequence, if the required conditions are not observed.

1. The DEMAND LED status indicator will light.

2. The unit checks to ensure that the Proof of Closure (POC) switch in the downstream Safety Shut-Off Valve (SSOV) is closed. See Figure 3-3 for SSOV locations.

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CONTROL PANEL OPERATING PROCEDURES

DIAL (DETAIL “A”)

TO BLOWER

STEPPER

MOTOR

100

DETAIL “A”

AIR IN

Figure 3-4.

Air/Fuel Valve In Purge Position

Figure 3-3.

SSOV Locations

3. With all required safety device switches closed, a purge cycle will be initiated and the following events will occur:

(a) The Blower relay energizes and turns

on blower.

(b) The Air/Fuel Valve rotates to the full-

open purge position and closes purge position switch. The dial on the Air/Fuel Valve (Figure 3-4) will read 100 to indicate that it is full-open (100%).

100%.

4. Next, the blower proof switch on the Air/Fuel Valve (Figure 3-5) closes. The display will show Purging and indicate the elapsed time of the purge cycle in seconds. The normal (default) time for the purge cycle is 7 seconds.

Figure 3-5.

Blower Proof Switch

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CONTROL PANEL OPERATING PROCEDURES

5. Upon completion of the purge cycle, the Control Box initiates an ignition cycle and the following events occur:

(a) The Air/Fuel Valve rotates to the low-

fire ignition position and closes the ignition switch. The dial on the Air/Fuel Valve (Figure 3-6) will read between 25 and 35 to indicate that the valve is in the low-fire position.

(b) The igniter relay is activated and

provides ignition spark.

is energized (opened) allowing gas to flow into the Air/Fuel Valve.

6. Up to 7 seconds will be allowed for ignition to be detected. The igniter relay will be turned off one second after flame is detected.

7. After 2 seconds of continuous flame, Flame Proven will be displayed and the flame strength will be indicated. After 5 seconds, the current date and time will be displayed in place of the flame strength.

8. With the unit firing properly, it will be controlled by the temperature controller circuitry. The boiler’s FIRE RATE will be continuously displayed on the front panel bargraph.

Once the demand for heat has been satisfied, the Control Box will turn off the dual SSOV gas valves. The blower relay will be deactivated and the Air/Fuel Valve will be closed. Standby will be displayed.

DIAL (DETAIL “A”)

STEPPER

MOTOR

DETAIL “A”

Figure 3-6.

Air/Fuel Valve In Ignition

3.9 START/STOP LEVELS

The start and stop levels are the fire rate percentages that start and stop the unit, based on load. These levels are Factory preset as follows:

Start Level: 20%

Stop Level: 14%

Normally, these settings should not require adjustment.

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Page 33

CH APTER 4 INITIAL START-UP

INITIAL START-UP

4.1 INITIAL START-UP REQUIREMENTS

The requirements for the initial start-up of the Benchmark 3.0 Boiler consists of the following:

• Complete installation

• Perform combustion calibration

• Set proper controls and limits

• Set up mode of operation (see Chapter 5)

• Test safety devices (see Chapter 6)

Installation should be fully completed before performing initial start-up; and the start-up must be complete prior to putting the unit into service. Starting a unit without the proper piping, venting, or electrical systems can be dangerous and may void the product warranty. The following start-up instructions should be followed precisely in order to operate the unit safely and at a high thermal efficiency, with low flue gas emissions.

Initial unit start-up is to be performed ONLY by AERCO factory trained start-up and service personnel. After following the steps in this chapter, it will be necessary to perform the Mode of Operation settings in Chapter 5, and the Safety Device Testing procedures in Chapter 6 to complete the initial unit start-up.

An AERCO Gas Fired Startup Sheet, included with each Benchmark Boiler, must be completed for each unit for warranty validation and a copy must be returned promptly to AERCO at:

AERCO International, Inc.

159 Paris Ave. Northvale, NJ 07647

CAUTION

All applicable installation procedures in Chapter 2 must be completed before attempting to start the unit.

4.2 TOOLS AND INSTRUMENTATION FOR COMBUSTION CALIBRATION

To properly perform combustion calibration, the proper instruments and tools must be used and correctly attached to the unit. The following paragraphs outline the necessary tools and instrumentation as well as their installation.

4.2.1 Required Tools & Instrumentation

The following tools and instrumentation are necessary to perform combustion calibration of the unit:

• Digital Combustion Analyzer: Oxygen accuracy to ± 0.4%; Carbon Monoxide (CO) and Nitrogen Oxide (NOx) resolution to 1PPM.

• 16 inch W.C. manometer or equivalent gauge and plastic tubing.

• 1/8 inch NPT-to-barbed fittings for use with gas supply manometer or gauge.

• Small and large flat blade screwdrivers.

• Tube of silicone adhesive

4.2.2 Installing Gas Supply Manometer

The gas supply manometer is installed in the gas train as follows:

1. Close the main manual gas supply shut-off valve upstream of the unit.

WARNING

2. Remove the front door and left side panels from the boiler to access the gas train components.

3. Remove the 1/8 inch NPT pipe plug from the leak detection ball valve on the downstream side of the Safety Shut Off Valve (SSOV) No. 1 as shown in Figure 4-1.

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INITIAL START-UP

4. Install a NPT-to-barbed fitting into the tapped plug port.

5. Attach one end of the plastic tubing to the barbed fitting and the other end to the 16 inch W.C. manometer.

Figure 4.2

Analyzer Probe Hole Location

Figure 4-1.

1/8 Inch Gas Plug Location

4.2.3 Accessing the Vent Probe Port

The unit contains NPT plugs on both the left and right side of the exhaust manifold at the rear of the unit as shown in Figure 4-2. Prepare the port for the combustion analyzer probe as follows:

1. Remove the plug from the probe port on the

right side of the exhaust manifold.

left or

2. If necessary, adjust the stop on the combustion analyzer probe so that it will extend mid-way into the flue gas flow. DO NOT install the probe at this time.

IMPORTANT

The Combustion Calibration procedure specified in paragraph 4.3 applies ONLY to units with serial numbers G-07-1901 and above.

For units with serial numbers below G-07-1901, use the Combustion Calibration procedure provided in Appendix K.

4.3 NATURAL GAS COMBUSTION CALIBRATION

The Benchmark 3.0LN Boiler is combustion calibrated at the factory prior to shipping. However, recalibration as part of initial start-up is necessary due to changes in the local altitude, gas BTU content, gas supply piping and supply regulators. Factory Test Data sheets are shipped with each unit. These sheets must be filled out and returned to AERCO for proper Warranty Validation.

It is important to perform the following procedure as outlined. This will keep readjustments to a minimum and provide optimum performance.

1. Open the water supply and return valves to the unit and ensure that the system pumps are running.

2. Open the natural gas supply valve(s) to the unit.

3. Set the control panel ON/ OFF switch to the OFF position.

4. Turn on external AC power to the unit. The

display will show LOSS OF POWER and the

time and date.

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INITIAL START-UP

5. Set the unit to the Manual Mode by pressing

the AUTO/MAN key. A flashing Manual Fire Rate message will be displayed with the present rate in %. Also, the MANUAL LED

will light.

6. Adjust the fire rate to 0% by pressing the ▼ arrow key.

7. Ensure that the leak detection ball valve down-stream of SSOV No. 2 is open.

8. Set the ON/OFF switch to the ON position.

9. Change the fire rate to 29% using the ▲ arrow key. The unit should begin its start sequence and fire.

10. Next, verify that the gas pressure downstream of SSOV No. 1 is 1.8” W.C. for both FM and IRI gas trains. If gas pressure adjustment is required, remove the brass hex nut on downstream SSOV No. 1 containing the gas pressure regulator (Figure 4-3). Make gas regulator adjustments using a flat-tip screwdriver to obtain

1.8” W.C.

11. Raise the firing rate to 100% and verify that the gas pressure downstream of SSOV No. 1 remains at 1.8” W.C. Readjust pressure if necessary.

12. With the firing rate at 100%, insert the combustion analyzer probe into the flue probe opening and allow enough time for the combustion analyzer to settle.

13. Compare the measured oxygen level to the oxygen range for the inlet air temperature shown in Table 4-1. Also, ensure that the carbon monoxide (CO) and nitrogen oxide (NOx) readings do not exceed the values shown.

Table 4-1

Combustion Oxygen Levels for a 100%

Firing Rate

Inlet Air

Temp

>100°F 4.8 % <100 ppm <30 ppm

90°F 5.0 % <100 ppm <30 ppm 80°F 5.2 % <100 ppm <30 ppm

<70°F 5.3 % <100 ppm <30 ppm

14. If necessary, adjust the iris air damper shown in Figure 4-4 until the oxygen level is within the range specified in Table 4-1.

Oxygen %

± 0.2

Carbon

Monoxide NOx

Figure 4-3

Regulator Adjustment Screw Location

15. Once the oxygen level is within the specified range at 100%, lower the firing rate to 70%.

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INITIAL START-UP

Figure 4-5

VFD Controls and Displays

17. Press the M (Menu) programming key on

the VFD.

18. Using the up (▲) arrow key, select VFD

parameter 65. The selected parameter will

appear in the left part of the display and the frequency (Hz) will appear in the right part of the display.

Figure 4-4

Iris Air Damper Location/Adjustment

NOTE

The remaining combustion calibration steps utilize the Variable Frequency Drive (VFD) located behind the front door of the unit. The VFD controls will be used to adjust the oxygen level (%) at firing rates of 70%, 50%, 40%, 30% and 14% as described in the following steps. These steps assume that the inlet air temperature is within the range of 50°F to 100°F.

16. Locate the Variable Frequency Drive (VFD) behind the front door of the unit. Refer to the VFD operating controls shown in Figure 4-5.

19. With the selected VFD parameter display

flashing, press the M key. Code will be

displayed, requesting the valid code to be

entered. Enter code 59 using the arrow

keys.

20. Press the M key again and observe the

frequency shown in the right part of the display. The oxygen level at the 70% firing rate should be as shown in the following tabular listing. Also, ensure that the carbon monoxide (CO) and nitrogen oxide (NOx) readings do not exceed the values shown.

Combustion Oxygen Level at

70% Firing Rate

Oxygen %

± 0.2

6.0 % <100 ppm <30 ppm

21. If the oxygen level is not within the specified range, adjust the level using the up (▲) and down (▼) arrow keys on the VFD. Using the up (▲) arrow key will increase oxygen level and the down (▼) arrow key will decrease the oxygen level.

Carbon

Monoxide

NOx

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INITIAL START-UP

22. Once the oxygen level is within the specified range at 70%, lower the firing rate to 50%

and select VFD parameter 64. The oxygen

level at the 50% firing rate should be as shown below.

Combustion Oxygen Level at

50% Firing Rate

Oxygen %

± 0.2

7.0 % <50 ppm <20 ppm

23. Adjust the oxygen level as necessary to obtain the required reading at the 50% firing rate.

24. Once the oxygen level is within the specified range at 50%, lower the firing rate to 40%

and select VFD parameter 63. The oxygen

level at the 40% firing rate should be as shown below.

Carbon

Monoxide

NOx

Combustion Oxygen Level at

40% Firing Rate

Oxygen %

± 0.2

7.8% <50 ppm <20 ppm

Carbon

Monoxide

NOx

NOTE

At a 14% fire rate, if parameter 61 is

above 326, the VFD software will use 326 by default. 326 corresponds to a frequency of 32.6 Hz.

Combustion Oxygen Level at

14% Firing Rate

Oxygen %

± 0.2

8.5 % <50 ppm <20 ppm

29. Adjust the oxygen level as necessary to obtain the required reading at the 14% firing rate.

30. This completes the combustion calibration procedures.

Carbon

Monoxide

NOx

4.4 UNIT REASSEMBLY

Once the combustion calibration adjustments are properly set, the unit can be reassembled for service operation.

25. Adjust the oxygen level as necessary to obtain the required reading at the 40% firing rate.

26. Next, set the firing rate to 30% and select

VFD parameter 62. The oxygen level at the

30% firing rate should be as shown below.

Combustion Oxygen Level at

30% Firing Rate

Oxygen %

± 0.2

8.0 % <50 ppm <20 ppm

27. Adjust the oxygen level as necessary to obtain the required reading at the 30% firing rate.

28. Finally, reduce the firing rate to 14% and

select VFD parameter 61. The oxygen level

at the 14% firing rate should be as shown in the following tabular listing:

Carbon

Monoxide

NOx

1. Set the ON/OFF switch in the OFF position.

2. Disconnect AC power from the unit.

3. Shut off the gas supply to the unit.

4. Remove the manometer and barbed fittings and reinstall the NPT plug using a suitable pipe thread compound.

5. Remove the combustion analyzer probe from the vent hole. Replace the NPT plug in the vent hole using a suitable pipe joint compound.

6. Replace the unit’s side panels and front door.

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INITIAL START-UP

4.5 OVER-TEMPERATURE LIMIT SWITCHES

The unit contains both automatic and manual reset over-temperature limit switches. These switches are mounted on a plate attached to the boiler shell as shown in Figure 4-6. The switches can be accessed by removing the left side panels of the unit. The manual reset switch is not adjustable and is permanently fixed at 210°F. This switch will shut down and lock out the boiler if the water temperature exceeds 210°F. Following an over-temperature condition, it must be manually reset by pressing the RESET button before the boiler can be restarted. The automatic reset over-temperature switch is adjustable and allows the boiler to restart, once the temperature drops below its temperature setting. Set the automatic overtemperature switch to the desired setting.

Figure 4-6

Over Temperature Limit Switch

Locations

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MODE OF OPERATION

CHAPTER 5 MODE OF OPERATION

5.1 INTRODUCTION

The Benchmark 3.0 Boiler is capable of being operated in any one of six different modes. The following paragraphs in this Chapter provide descriptions of each of these operating modes. Each Benchmark 3.0 Boiler is shipped from the factory tested and configured for the ordered mode of operation. All temperature related parameters are at their factory default values which work well in most applications. However, it may be necessary to change certain parameters to customize the unit to the system environment. A complete listing and descriptions of the temperature related parameters are included in Appendix A. Factory defaults are listed in Appendix E. After reading this chapter, parameters can be customized to suit the needs of the specific application.

5.2 INDOOR/OUTDOOR RESET MODE

This mode of operation is based on outside air temperatures. As the outside air temperature decreases, the supply header temperature will increase and vice versa. For this mode, it is necessary to install an outside air sensor as well as select a building reference temperature and a reset ratio.

5.2.1 Reset Ratio

Reset ratio is an adjustable number from 0.1 to

9.9. Once adjusted, the supply header temperature will increase by that number for each degree that the outside air temperature decreases. For instance, if a reset ratio of 1.6 is used, for each degree that outside air temperature decreases the supply header temperature will increase by 1.6 degrees.

5.2.3 Outdoor Air Temperature Sensor

Installation

The outdoor air temperature sensor must be mounted on the North side of the building in an area where the average outside air temperature is expected. The sensor must be shielded from the sun's direct rays, as well as direct impingement by the elements. If a cover or shield is used, it must allow free air circulation. The sensor may be mounted up to two hundred feet from the unit. Sensor connections are made at the Input/Output (I/O) Box on the front of the Benchmark 3.0 Boiler. Connections are made at the terminals labeled OUTDOOR SENSOR IN and SENSOR COMMON inside the I/O Box. Use shielded 18 to 22 AWG wire for connections. A wiring diagram is provided on the cover of the I/O Box. Refer to Chapter 2, paragraph 2.9.1 for additional wiring information.

5.2.4 Indoor/ Outdoor Startup

Startup in the Indoor/Outdoor Reset Mode is accomplished as follows:

1. Refer to the Indoor/Outdoor reset ratio charts in Appendix D.

2. Choose the chart corresponding to the desired Building Reference Temperature.

3. Go down the left column of the chart to the coldest design outdoor air temperature expected in your area.

NOTE

A design engineer typically provides design outdoor air temperature and

header temperature data

supply

5.2.2 Building Reference Temperature

This is a temperature from 40°F to 230°F. Once selected, it is the temperature that the system references to begin increasing its temperature. For instance, if a reset ratio of 1.6 is used, and we select a building reference temperature of 70°F, then at an outside temperature of 69°F, the supply header temperature will increase by

1.6° to 71.6°F.

4. Once the design outdoor air temperature is chosen, go across the chart to the desired supply header temperature for the design temperature chosen in step 3.

5. Next, go up that column to the Reset Ratio row to find the corresponding reset ratio.

6. Access the Configuration Menu and scroll through it until the display shows Bldg Ref Temp. (Building Reference Temperature).

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MODE OF OPERATION

7. Press the CHANGE key. The display will begin to flash.

8. Use the ▲ and ▼ arrow keys to select the desired Building Reference Temperature.

9. Press ENTER to save any changes.

10. Next, scroll through the Configuration Menu until the display shows Reset Ratio.

11. Press the CHANGE key. The display will begin to flash.

12. Use the ▲ and ▼ arrow keys to select the Reset Ratio determined in step 5.

13. Press ENTER to save the change.

Refer to paragraph 3.3 for detailed instructions on menu changing.

5.3 CONSTANT SETPOINT MODE

The Constant Setpoint mode is used when a fixed header temperature is desired. Common uses of this mode of operation include water source heat pump loops, and indirect heat exchangers for potable hot water systems or processes.

5.4 REMOTE SETPOINT MODES

The unit’s setpoint can be remotely controlled by an Energy Management System (EMS) or Building Automation System (BAS). The Remote Setpoint can be driven by a current or voltage signal within the following ranges:

4-20 mA/1-5 Vdc

0-20 mA/0-5 Vdc

The factory default setting for the Remote Setpoint mode is 4 - 20 mA/1 - 5 Vdc. With this setting, a 4 to 20 mA/1 to 5 Vdc signal, sent by an EMS or BAS, is used to change the unit's setpoint. The 4 mA/1V signal is equal to a 40°F setpoint while a 20 mA /5V signal is equal to a 240°F setpoint. When a 0 to 20 mA/0 to 5 Vdc signal is used, 0 mA is equal to a 40°F setpoint.

In addition to the current and voltage signals described above, the Remote Setpoint mode can also driven by a RS485 Modbus Network signal from an EMS or BAS.

The Remote Setpoint modes of operation can be used to drive single as well as multiple units.

No external sensors are required to operate in this mode. While it is necessary to set the desired setpoint temperature, it is not necessary to change any other temperature-related functions. The unit is factory preset with settings that work well in most applications. Prior to changing any temperature-related parameters, other than the setpoint, it is suggested that an AERCO representative be contacted. For descriptions of temperature-related functions and their factory defaults, see Appendices A and E.

5.3.1 Setting the Setpoint

The setpoint temperature of the unit is adjustable from 40°F to 240°F. To set the unit for operation in the Constant Setpoint Mode, the following menu settings must be made in the Configuration Menu:

MENU OPTION SETTING

Boiler Mode Constant Setpoint

Internal Setpt Select desired setpoint

using ▲ and ▼ arrow keys (40°F to 240°F)

NOTE

If a voltage, rather than current signal is used to control the remote setpoint, a DIP switch adjustment must be made on the PMC Board located in the Control Panel Assembly. Contact your local AERCO representative for details.

In order to enable the Remote Setpoint Mode, the following menu setting must be made in the Configuration Menu:

MENU OPTION SETTING

Boiler Mode Remote Setpoint

Remote Signal 4-20mA/1-5V,

0-20mA/0-5V, or

Network

Refer to paragraph 3.3 for detailed instructions on changing menu options.

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MODE OF OPERATION

If the Network setting is selected for RS485 Modbus operation, a valid Comm Address must be entered in the Setup Menu. Refer to Modbus Communication Manual GF-114 for additional information.

While it is possible to change the settings of temperature related functions, the unit is factory preset with settings that work well in most applications. It is suggested that an AERCO representative be contacted, prior to changing any temperature related function settings. For descriptions of temperature-related functions and their factory defaults, refer to Appendices A and E.

5.4.1 Remote Setpoint Field Wiring

The only wiring connections necessary for the Remote Setpoint mode are connection of the remote signal leads from the source to the unit’s I/O Box. The I/O Box is located on the front panel of the Benchmark 3.0 Boiler. For either a 4-20mA/0-5V or a 0-20mA/0-5V setting, the connections are made at the ANALOG IN terminals in the I/O Box. For a Network setting, the connections are made at the RS-485 COMM terminals in the I/O Box. The signal must be floating, (ungrounded) at the I/O Box and the wire used must be a two wire shielded pair from 18 to 22 AWG. Polarity must be observed. The source end of the shield must be connected at the source. When driving multiple units, each unit’s wiring must conform to the above.

5.4.2 Remote Setpoint Startup

Since this mode of operation is factory preset and the setpoint is being externally controlled, no startup instructions are necessary. In this mode, the REMOTE LED will light when the external signal is present.

To operate the unit in the Manual mode, press the AUTO/MAN switch. The REMOTE LED will go off and the MANUAL LED will light.

To change back to the Remote Setpoint mode, simply press the AUTO/MAN switch. The REMOTE LED will again light and the MANUAL LED will go off.

5.5 DIRECT DRIVE MODES

The unit’s fire rate can be changed by a remote signal which is typically sent from an Energy Management System (EMS) or from a Building Automation System (BAS). The Direct Drive mode can be driven by a current or voltage signal within the following ranges:

4-20 mA/1-5 Vdc

0-20 mA/0-5 Vdc

The factory default setting for the Direct Drive mode is 4-20 mA/1-5 Vdc. With this setting, a 4 to 20 mA signal, sent by an EMS or BAS is used to change the unit’s fire rate from 0% to 100%. A 4 mA/1V signal is equal to a 0% fire rate, while a 20 mA /5V signal is equal to a 100% fire rate. When a 0-20 mA/0-5 Vdc signal is used, zero is equal to a 0% fire rate.

In addition to the current and voltage signals described above, the Direct Drive mode can also driven by a RS485 Modbus Network signal from an EMS or BAS.

When in a Direct Drive mode, the unit is a slave to the EMS or BAS and does not have a role in temperature control. Direct Drive can be used to drive single, or multiple units.

NOTE

If a voltage, rather than current signal is used to control the remote setpoint, a DIP switch adjustment must be made on the PMC Board located in the Control Box Assembly. Contact your local AERCO representative for details.

To enable the Direct Drive Mode, the following menu setting must be made in the Configuration Menu:

MENU OPTION SETTING

Boiler Mode Direct Drive

Remote Signal 4-20mA/1-5V,

0-20mA/0-5V, or

Network

Refer to paragraph 3.3 for instructions on changing menu options.

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MODE OF OPERATION

If the Network setting is selected for RS485 Modbus operation, a valid Comm Address must be entered in the Setup Menu. Refer to Modbus Communication Manual GF-114 for additional information.

5.5.1 Direct Drive Field Wiring

The only wiring connections necessary for Direct Drive mode are connection of the remote signal leads from the source to the unit’s I/O Box. For either a 4-20mA/0-5V or a 0-20mA/0-5V setting, the connections are made at the ANALOG IN terminals in the I/O Box. For a Network setting, the connections are made at the RS-485 COMM terminals in the I/O Box. The signal must be floating, (ungrounded) at the I/O Box and the wire used must be a two wire shielded pair from 18 to 22 AWG. Polarity must be observed. The source end of the shield must be connected at the source. When driving multiple units, each unit’s wiring must conform to the above.

5.5.2 Direct Drive Startup

Since this mode of operation is factory preset and the fire rate is being externally controlled, no startup instructions are necessary. In this mode, the REMOTE LED will light when the signal is present.

To operate the unit in manual mode, press the AUTO/MAN switch. The REMOTE LED will go off and the MANUAL LED will light.

To change back to the Direct Drive mode, simply press the AUTO/MAN switch. The REMOTE LED will again light and the MANUAL LED will go off.

5.6 BOILER MANAGEMENT SYSTEM

(BMS)

NOTE

BMS Model 168 can utilize either pulse width modulation (PWM) or RS485 Modbus signaling to the Boiler. BMS II Model 5R5-384 can utilize only RS485 signaling to the Boiler.

The BMS mode of operation is used in conjunction with an AERCO Boiler Management System. The BMS mode is used when it is desired to operate multiple units in the most efficient manner possible. The BMS can control up to 40 boilers; 8 via pulse width modulation (PWM) and up to 32 via Modbus (RS485)

network communication. For BMS programming and operation, see GF-108M (BMS Model 168) and GF-124 (BMS II Model 5R5-384), BMS Operations Guides. For operation via an RS485 Modbus network, refer to Modbus Communication Manual GF-114.

To enable the BMS Mode, the following menu settings must be made in the Configuration Menu:

MENU OPTION SETTING

Boiler Mode Direct Drive

Remote Signal BMS (PWM Input)

or Network (RS485)

Refer to paragraph 3.3 for instructions on changing menu options.

5.6.1 BMS External Field Wiring

Wiring connections for BMS control using PWM signaling are made between connector JP2 on the BMS panel (boilers 1 through 8), and the B.M.S. (PWM) IN terminals in the I/O Box on the front of the Benchmark 3.0 Boilers. Refer to the wiring diagram provided on the cover of the I/O Box.

Wiring connections for RS485 Modbus control are made between connector JP11 on the BMS (boilers 9 through 40) and the RS485 COMM terminals in the I/O Box on the front of the Benchmark 3.0 Boilers.

Wire the units using shielded twisted pair wire between 18 and 22 AWG. Observe the proper polarity for the B.M.S. (PWM) IN and/or RS485 COMM wiring connections. Shields should be terminated only at the BMS and the boiler end must be left floating. Each unit’s wiring must conform to the above.

5.6.2 BMS Setup and Startup

This mode of operation is factory preset and the AERCO BMS controls the firing rate. There are no setup instructions for each individual unit.

To operate the unit in manual mode, press the AUTO/MAN switch. The REMOTE LED will go off and the MANUAL LED will light

To change back to the BMS mode, simply press the AUTO/MAN switch. The REMOTE LED will again light and the MANUAL LED will go off.

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MODE OF OPERATION

5.7 COMBINATION CONTROL SYSTEM

(CCS)

NOTE

Only BMS Model 168 can be utilized for the Combination Mode, not the BMS II (Model 5R5-384).

A Combination Control System (CCS) is one that uses multiple boilers to cover both spaceheating and domestic hot water needs. An AERCO Boiler Management System (BMS) Model 168 and a Combination Control Panel (CCP) are necessary to configure this system. Typically, an adequate number of boilers are installed to cover the space-heating load on the design day, however one or more units are used for the domestic hot water load.

The theory behind this type of system is that the maximum space-heating load and the maximum domestic hot water load do not occur simultaneously.+ Therefore, boilers used for the domestic hot water are capable of switching between constant setpoint and BMS modes of operation. These boilers are the combination units and are referred to as the combo boilers. The combo boilers heat water to a constant setpoint temperature. That water is then circulated through a heat exchanger in a domestic hot water storage tank.

When the space-heating load is such that all the space-heating boilers are at 100% firing rate, the BMS will then ask the Combination Control Panel for the domestic boilers to become spaceheating boilers. Provided the domestic hot water load is satisfied, the combo (hot water) boilers will then become space-heating boilers. If the domestic hot water load is not satisfied, the combo boiler(s) remain on the domestic hot water load. If the combo boilers switch over to space heating, but there is a call for domestic hot water, the CCP switches the combo units back to the domestic load.

When the combo units are satisfying the domestic load they are in constant setpoint mode of operation. When the combo units switch over to space heating, their mode of operation changes to the BMS mode. For more information concerning the operation of the Combination Control Panel see the AERCO CCP-1 literature.

5.7.1 Combination Control System Field Wiring

Wiring for this system is between the BMS Model 168 panel, the CCP and the B.M.S. (PWM) IN terminals in the I/O Box. Wire the units using a shielded twisted pair of 18 to 22 AWG wire. When wiring multiple units, each unit’s wiring must conform to the above. For a complete CCP system-wiring diagram see the AERCO CCP-1 literature.

5.7.2 Combination Control System Setup and Startup

Setup for the Combination Mode requires entries to be made in the Configuration Menu for boiler mode, remote signal type and setpoint. The setpoint is adjustable from 40°F to 240°F.

Enter the following settings in the Configuration Menu:

MENU OPTION SETTING

Boiler Mode Combination

Remote Signal BMS (PWM Input)

Internal Setpt 40°F to 240°F

Refer to paragraph 3.3 for instructions on changing menu options.

While it is possible to change other temperaturerelated functions for combination mode, thes functions are preset to their factory default values. These default settings work well in most applications. It is suggested that AERCO be contacted prior to changing settings other than the unit’s setpoint. For a complete listing of temperature related function defaults, see Appendix E.

To set the unit to the manual mode, press the AUTO/MAN switch. The MANUAL LED will light.

To set the unit back to the auto mode, press the AUTO/MAN switch. The MANUAL LED will go off and the REMOTE LED will light.

When the boiler is switched to BMS mode, the AERCO BMS controls the firing rate. There are no setup requirements to the boiler(s) in this mode.

5-5

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SAFETY DEVICE TESTING

CHAPTER 6 SAFETY DEVICE TESTING

6.1 TESTING OF SAFETY DEVICES

Periodic safety device testing is required to ensure that the control system and safety devices are operating properly. The Benchmark

3.0LN control system comprehensively monitors

all combustion-related safety devices before, during and after the start sequence. The following tests check to ensure that the system is operating as designed.

Operating controls and safety devices should be tested on a regular basis or following service or replacement. All testing must conform to local codes such as ASME CSD-1.

NOTE

MANUAL and AUTO modes of operation are required to perform the following tests. For a complete explanation of these modes, see Chapter 3.

NOTE

It will be necessary to remove the front door and side panels from the unit to perform the following tests.

4. Place the unit in Manual Mode and adjust the firing rate between 25 and 30%.

5. While the unit is firing, slowly external manual gas shut-off valve.

6. The unit should shut down and display a LOW GAS PRESSURE fault message at approximately 2.6” W.C. The FAULT indicator should also start flashing.

close the

WARNING

ELECTRICAL VOLTAGES IN THIS SYSTEM MAY INCLUDE 460, 220, 120 AND 24 VOLTS AC. POWER MUST BE REMOVED PRIOR TO PERFORMING WIRE REMOVAL OR OTHER TEST PROCEDURES THAT CAN RESULT IN ELECTRICAL SHOCK.

6.2 LOW GAS PRESSURE FAULT TEST

Refer to Figure 6-1 and ensure that the leak detection ball valve located at the high gas pressure switch is closed.

1. Remove the 1/8 “ plug from the ball valve at the low gas pressure switch shown in the lower portion of Figure 6-1.

2. Install a 0 – 16 “ W.C. manometer or a W.C. gauge where the 1/8" plug was removed.

3. Slowly open the ball valve near the low gas pressure switch.

Figure 6-1

Low & High Gas Pressure Testing

7. Fully open the external manual gas shut-off valve and press the CLEAR button on the Control Box.

8. The fault message should clear and the FAULT indicator should go off. The unit should restart.

9. Upon test completion, close the ball valve and remove the manometer. Replace the 1/8 “ plug removed in step 1.

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SAFETY DEVICE TESTING

6.3 HIGH GAS PRESSURE TEST

To simulate a high gas pressure fault, refer to Figure 6-1 and proceed as follows:

1. Remove the 1/8 “ plug from the leak detection ball valve shown in the upper portion of Figure 6-1.

2. Install a 0 – 16” W.C. manometer (or W.C. gauge) where the 1/8” plug was removed.

3. Slowly open the leak detection ball valve

4. Start the unit in Manual mode at a firing rate between 25 and 30%.

5. Slowly increase the gas pressure using the adjustment screw on SSOV No. 1.

6. The unit should shut down and display a HIGH GAS PRESSURE fault message when the gas pressure exceeds 2.6” W.C. The FAULT indicator should also start flashing.

7. Reduce the gas pressure back to 1.7” W.C.

8. Press the CLEAR button on the Control Box to clear the fault.

unit should not start. If the unit does start, shut the unit off immediately and refer fault to qualified service personnel.

7. Close the drain and pressure relief valve used in draining the unit.

8. Open the water shut-off valve in the return piping to the unit.

9. Open the water supply shut-off valve to the unit to refill.

10. After the shell is full, press the LOW WATER LEVEL RESET button to reset the low water cutoff.

11. Press the CLEAR button to reset the FAULT LED and clear the displayed error message.

12. Set the ON/OFF switch to the ON position. The unit is now ready for operation.

6.5 WATER TEMPERATURE FAULT

TEST

A high water temperature fault is simulated by adjusting the automatic over-temperature switch. This switch is accessible from the left side of the unit as shown in Figure 6-2.

9. The fault message should clear and the FAULT indicator should go off. The unit should restart.

10. Upon test completion, close the ball valve and remove the manometer. Replace the 1/8“ plug removed in step 1.

6.4 LOW WATER LEVEL FAULT TEST

To simulate a low water level fault:

1. Set the ON/OFF switch to the OFF position

2. Close the water shut-off valves in the supply and return piping to the unit.

3. Slowly open the drain valve on the rear of the unit. If necessary the unit’s relief valve may be opened to aid in draining.

4. Continue draining the unit until a LOW WATER LEVEL fault message is displayed and the FAULT indicator flashes.

5. Place the unit in the Manual Mode and raise the firing rate above 30%.

1. Start the unit in the normal operating mode. Allow the unit to stabilize at its setpoint.

2. Lower the adjustable over-temperature switch setting to match the displayed OUTLET TEMPERATURE.

3. Once the adjustable over-temperature switch setting is approximately at, or just below, the actual outlet water temperature, the unit should shut down. The FAULT indicator should start flashing and a HIGH WATER TEMP SWITCH OPEN fault message should be displayed. It should not be possible to restart the unit.

4. Reset the adjustable over-temperature switch to its original setting.

5. The unit should start once the adjustable temperature limit switch setting is above the actual outlet water temperature.

6. Set the ON/OFF switch to the ON position. The READY light should remain off and the

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SAFETY DEVICE TESTING

that a device such as a pump, gas booster, or louver is operational.

6.6.1 REMOTE INTERLOCK

1. Remove the cover from the I/O Box and locate the REMOTE INTL’K IN terminals.

2. Start the unit in the Manual Mode and set the firing rate between 25% and 30%.

3. If there is a jumper across the REMOTE INTL’K IN terminals, remove one side of the jumper. If the interlock is being controlled by an external device, either open the interlock via the external device or disconnect one of the wires leading to the external device.

4. The unit should shut down and display INTERLOCK OPEN.

5. Once the interlock connection is reconnected, the INTERLOCK OPEN message should automatically clear and the unit should restart.

Figure 6-2

Temperature Limit Switch Setting

6. Once the adjustable over-temperature switch setting is approximately at, or just below, the actual outlet water temperature, the unit should shut down. The FAULT indicator should start flashing and a HIGH WATER TEMP SWITCH OPEN fault message should be displayed. It should not be possible to restart the unit.

7. Reset the adjustable over-temperature switch to its original setting.

8. The unit should start once the adjustable temperature limit switch setting is above the actual outlet water temperature.

6.6 INTERLOCK TESTS

The unit is equipped with two interlock circuits called the Remote Interlock and Delayed Interlock. Terminal connections for these circuits are located in the I/O Box (Figure 2-9) and are labeled REMOTE INTL’K IN and DELAYED INTL’K IN. These circuits can shut down the unit in the event that an interlock is opened. These interlocks are shipped from the factory jumpered (closed). However, each of these interlocks may be utilized in the field as a remote stop and start, an emergency cut-off, or to prove

6.6.2 DELAYED INTERLOCK

1. Remove the cover from the I/O Box and locate the DELAYED INTL’K IN terminals.

2. Start the unit in the Manual Mode at a firing rate between 25% and 30%.

3. If there is a jumper across the DELAYED INTL’K IN terminals, remove one side of the jumper. If the interlock is connected to a proving switch of an external device, disconnect one of the wires leading to the proving switch.

4. The unit should shut down and display a DELAYED INTERLOCK OPEN fault message. The FAULT LED should be flashing.

5. Reconnect the wire or jumper removed in step 3 to restore the interlock.

6. Press the CLEAR button to reset the fault

7. The unit should start.

6.7 FLAME FAULT TESTS

Flame faults can occur during ignition or while the unit is already running. To simulate each of these fault conditions, proceed as follows:

1. Set the ON/OFF switch to the OFF position.

2. Place the unit in the Manual Mode and set the firing rate between 25% and 30%.

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SAFETY DEVICE TESTING

3. Close the manual gas shutoff valve located between the Safety Shut-Off Valve (SSOV) and the Air/Fuel Valve (see Figure 6-3).

4. Set the ON/OFF switch to the ON position to start the unit.

5. The unit should shut down after reaching the Ignition cycle and display FLAME LOSS

DURING IGN.

6. Open the valve previously closed in step 3 and press the CLEAR button.

7. Restart the unit and allow it to prove flame.

8. Once flame is proven, close the manual gas valve located between the SSOV and the Air/Fuel Valve.

9. The unit should shut down and display FLAME LOSS DURING RUN.

10. Open the valve previously closed in step 8.

11. Press the CLEAR button. The unit should restart and fire.

AIR

INLET

BLOCKED

INLET

SWITCH

BLOWER PROOF

SWITCH

BLOWER

6.8 AIR FLOW FAULT TESTS

These tests check the operation of the Blower Proof Switch and Blocked Inlet Switch shown in Figure 6-3.

1. Start the unit in the Manual Mode at a firing rate between 25% and 30%.

2. Once the unit has proved flame, remove the memory stick from the Variable Frequency Drive (VFD).

3. The Blower Proof Switch will open and the blower should stop. The unit should shut down and display AIRFLOW FAULT DURING RUN.

4. Replace the memory stick in the VFD.

5. Press the CLEAR button. The unit should restart.

6. Next, check the Blocked Inlet Switch by closing the Iris Air Damper to position 8.

7. .The unit should shut down and again display AIRFLOW FAULT DURING RUN.

8. Return the Iris Air Damper to its previous setting.

9. Press the CLEAR button. The unit should restart.

AIR/FUEL

VALVE

MANUAL GAS

SHUTOFF

VALVE

HANDLE

GAS

INLET

PARTIAL LEFT SIDE VIEW

Figure 6-3

Manual Gas Shut-Off Valve Location

6.9 SSOV PROOF OF CLOSURE SWITCH

The downstream SSOV (#1) shown in Figure 6-1 contains the proof of closure switch. The proof of closure switch circuit is checked as follows:

1. Set the unit’s ON/OFF switch to the OFF position.

2. Place the unit in Manual Mode and set the firing rate between 25% and 30%

3. Refer to Figure 6-1 and locate downstream SSOV #1.

4. Remove the cover from SSOV #1 by loosening the screw shown in Figure 6-4. Lift off the cover to access the terminal wiring connections.

5. Disconnect wire #148 from SSOV #1 to “open” the proof of closure switch circuit.

6. The unit should fault and display SSOV SWITCH OPEN.

7. Replace wire #148 and press the CLEAR button.

6-4

Page 49

SAFETY DEVICE TESTING

8. Set the ON/OFF switch to ON to start the unit.

9. Remove the wire again when the unit reaches the purge cycle and PURGING is displayed.

10. The unit should shut down and display SSOV FAULT DURING PURGE.

11. Replace the wire on SSOV #1 and press the CLEAR button. The unit should restart.

Figure 6-4

SSOV #1 Actuator Cover Location

6.11 IGNITION SWITCH OPEN DURING IGNITION

The Ignition Switch (and the Purge Switch) is located on the Air/Fuel Valve. To check the switch, proceed as follows:

1. Set the unit’s ON/OFF switch to the OFF position.

2. Place the unit in Manual Mode and set the firing rate between 25% and 30%.

3. Remove the Air/Fuel Valve cover (Figure 6-5) by rotating the cover counterclockwise to unlock and lift up to remove.

4. Remove one of the two wires (#169 or #170) from the Ignition Switch (Figure 6-6).

5. Initiate a unit start sequence.

6. The unit should begin it’s start sequence and then shut down and display IGN SWITCH OPEN DURING IGNITION.

7. Replace the wire on the Ignition Switch and press the CLEAR button. The unit should restart.

6.10 PURGE SWITCH OPEN DURING PURGE

The Purge Switch (and Ignition Switch) is located on the Air/Fuel Valve. To check the switch, proceed as follows:

1. Set the unit’s ON/OFF switch to the OFF position. Place the unit in manual mode and set the fire rate between 25% and 30%.

2. Remove the Air/Fuel Valve cover by rotating the cover counterclockwise to unlock it and then lift up (see Figure 6-5).

3. Remove one of the two wires (#171 or #172) from the Purge Switch (Figure 6-6).

4. Initiate a unit start sequence.

5. The unit should begin it’s start sequence, then shut down and display PRG SWITCH OPEN DURING PURGE.

6. Replace the wire on the Purge Switch and depress the CLEAR button. The unit should restart.

Figure 6-5

Air/Fuel Valve Cover Location

6-5

Page 50

SAFETY DEVICE TESTING

Figure 6-6

Air/Fuel Valve Purge and Ignition Switch

Locations

6.12 SAFETY PRESSURE RELIEF

VALVE TEST

Test the safety Pressure Relief Valve in accordance with ASME Boiler and Pressure Vessel Code, Section VI.

6-6

Page 51

MAINTENANCE

CHAPTER 7 MAINTENANCE

7.1 MAINTENANCE SCHEDULE

The unit requires regular routine maintena nce to keep up efficiency and reliability. For best operation and life of the unit, the following routine maintenance procedures should be carried out in the tim e periods spec ified in T able 7-1. See Appendix I for a complete CSD-1 inspection check list.

WARNING

TO AVOID PERSONAL, PRIOR TO SERVICING:

• DISCONNECT THE AC SUPPLY BY TURNING OFF THE SERVICE SWITCH AND AC SUPPLY CIRCUIT BREAKER.

• SHUT OFF THE GAS SUPPLY AT THE MANUAL SHUT-OFF VALVE PROVIDED WITH THE UNIT

• ALLOW THE UNIT TO COOL TO A SAFE WATER TEMPERATURE TO PREVENT BURNING OR SCALDING

5. The igniter is gapped at 1/8-inch. If there is a substantial erosion of the spark gap or ground electrode, the igniter should be replaced. If carbon buil d-up is pres ent, clean the igniter using fine emery cloth. Repeate d carbon build-up on the igniter is an indication that a check of the combustion settings is required (see Chapter 4 for combustion calibration.

6. Prior to reinstalling the igniter, a high temperature anti-seize compound must applied to the igniter threads.

7. Reinstall the igniter. Do not over tig hten the igniter. A slight snugging up is sufficient. Reconnect the igniter cable.

8. Reinstall the side and top panels on the unit.

7.2 SPARK IGNITER

The spark igniter, part no. GP-122435-S, is located in the bod y of the burner (see Figure 7-

1). The igniter may be HOT. Care should be exercised. It is easier to re move the igniter from the unit after the unit has cooled to room temperature.

To inspect/replace the Igniter:

1. Set the ON/OFF switch on the con trol pa nel, to the OFF position. Disconnect AC power from the unit

2. Remove the side and top panels from the unit.

3. Disconnect the igniter cable from the igniter.

4. Using a 15/16” wrench, unscrew the igniter from the burner head. Remove the igniter from the burner shell, by grasping the contact end of the igniter.

Figure 7-1

Spark Igniter and Flame Detector

Location – Top View

7-1

Page 52

MAINTENANCE

Table 7-1 - Maintenance Schedule

PARAGRAPH I TEM 6 Mos. 12 Mos. 24 Mos.

7.2

7.3

7.4

7.5

7.6 Burner Inspect 2 hrs.

7.7

* Only performed after initial 6 month period after initial startup.

7.3 FLAME DETECTOR

The flame detector, part no. 66006 , is located in the body of the burner (see Fig. 7-1) . The flame detector may be HOT. Allow the unit to cool sufficiently before removing the flame detector.

To inspect or replace the flame detector:

1. Set the ON/O FF s witch on the c ontrol panel , to the OFF position. Disconnect AC power from the unit.

2. Remove the top panels from the unit.

3. Disconnect the flame detector lead wire. Unscrew the flame detector and remove it. (See Fig 7-2)

Spark Igniter Flame

Detector

Combustion

Calibration

Testing of

Safety

Devices

Condensate Drain Traps

*Inspect Inspect Replace 15 mins. *Inspect Inspect Replace 15 mins.

*Check Check 1 hr.

See CSD-1

Chart in

20 mins.

Appendix I

*Inspect

Inspect &

Clean

BURNER

HOUSING

SPARK

IGNITER

1 hr.

Labor

Time

FLAME DETECTOR

4. Inspect the detector thoroughly. If eroded, the detector should be replac ed. Otherwise clean the detector with a fine emery cloth.

5. Reinstall the flame detector and flame detector gasket, if removed.

6. Reconnect the flame detector lead wire.

7. Reinstall the side and top panels on the unit.

7.4 COMBUSTION CALIBRATION

Combustion settings must be checked at the intervals shown in Table 7-1 as part of the maintenance requirem ents. Refer to Chapter 4 for combustion calibration instructions.

7-2

Figure 7-2

Spark Igniter and Flame Detector

Location Cut-Away View

Page 53

7.5 SAFETY DEVICE TESTING

Systematic and thorough tests of the operating and safety devices should be performed to ensure that they are operating as designed. Certain code requirements, such as ASME CSD-1, require that t hese tests be perform ed on a scheduled basis. Test schedules must conform to local jurisdictions. The results of the tests should be recorded in a log book. See Chapter 6-Safety Device Testing Procedures.

7.6 BURNER

The burner assem bly is located at the top front of the unit. The burner as sembly ma y be HOT. Allow the unit to cool sufficiently before removing the burner assembly.

The following parts will be necessary for reassembly after inspection :

Part No. Description

81030 Burner Gaskets (Qty=2) 81047 Gas Injector Gasket (Qty=1)

To inspect or replace the burner assembly:

1. Set the ON/OFF switch on the con trol pa nel, to the OFF position. Disconnect AC power from the unit and turn off the gas supply.

MAINTENANCE

9. Remove the grounding screw.

10. If there is an extension ring around the burner, remove it.

11. Remove the burner by pulling straight up.

12. Remove and replace the burner gaskets.

13. Beginning with the burner removed in step 11, reinstall all the components in the reverse order that they were removed. However, if the burner wa s replaced, follow the instructions in step 14.

14. If the burner is being replac ed, measure the outside diameter (O.D.) of the new burner flange. If the O.D. is approximately 13”, do

reinstall the extension ring. However, if

not the O.D. of the new burner flange is approximately 12.4”, t he ex tensio n ring must be reinstalled.

15. Make sure to align the Spark Igniter (S/I) and Flame Rod (F/R) s l ots in the burn er with the heat exchanger top head.

16. Check to ensure that the ground ing screw is reinstalled.

3/8-16 NUTS (8)

STAGED IGNITION ASSEMBLY

10-32 SCREWS (2)

2. Remove the side and top panels from the unit.

3. Disconnect the lead wire from the flame detector. Unscrew the flame detector.

4. Disconnect the igniter cabl e from the igniter contactor. Unscrew the igniter.

5. Remove the two (2) 10-32 screws securing the gas injector to the burner. Sep arate the gas injector and gasket from the burner.

6. Disconnect the burner housing from the blower by removing the six (6) 1/4-20 screws using a 3/8” wrench.

7. Remove the eight (8) 3/8-16 nuts from the burner flange (Figure 7-3) using a 9/16” wrench.

NOTE

The burner housing is heavy, weighing approximately 20 pounds.

8. Remove the burner housing from burner flange by pulling straight up.

GROUNDING SCREW

BURNER

BURNER HOUSING

1/4-20 SCREWS (6)

Figure 7-3

Burner Disassembly Diagram

7-3

Page 54

MAINTENANCE

7.7 CONDENSATE DRAIN TRAPS

The Benchmark 3.0 Boiler contains two condensate traps as shown in Figure 2-5. One trap is located external to t he unit and attached to the drain pipe from the connecting manifold. The other trap is an integr al part of the exhaust manifold. These tr aps should be inspected and, if necessary, cleaned to ensure proper operation. Follow the proc edures in paragraphs

7.7.1 and 7.7.2.

7.7.1 Connecting Manifold Condensate

Trap

To inspect and clean the trap, proceed as follows:

1. Disconnec t the external condensate trap by loosening the hose c lam ps between the trap and the connecting manifold drain pipe.

2. Remove the connections on the inlet and outlet sides of the condensate tr ap shown in Figure 7-4.

3. Loosen the four (4) thumbscrews securing the cover on the condensate trap. Remove the cover.

4. Remove the float from the condensate trap.

5. Remove the orifice gasket from the trap.

6. Thoroughly clean the trap, f loat and gasket. Also inspect the drain pipin g for blockage. If the trap cannot be thoroughly cleaned, replace the trap.

7. After the above it ems have been inspected and thoroughly cleaned, replace the orifice gasket and float in the condensat e trap and replace the trap cover.

8. Reassemble all piping and hose connections to the condensate trap inlet and outlet. Reconnect trap to conn ecting manif old drain pipe.

Figure 7-4

External Condensate Trap

7.7.2 Exhaust Manifold Condensate Trap

The exhaust manifold condensate trap also contains a float and orifice gasket identical to those shown in Fi gure 7-4. To inspec t and clea n the trap, refer to Figure 7-5 and proceed as follows:

1. Loosen the clamp securing the hose to the condensate drain (Figure 7-5). Disconnect the hose.

2. Remove the four bolts securing the flue to the top of the exhaust manifold. Separate the flue from the exhaust manifold.

3. From the top of the exhaust manifold, remove the float and or ifice gasket from the condensate trap.

4. Thoroughly clean the trap, f loat and gasket. Also, inspect the drain hose for blockage.

5. After the above it ems have been inspected and cleaned, replace the g asket and float in the condensate trap.

6. Replace the four bolts securing the flue to the exhaust manifold and connect the hose to the manifold condensate drain.

7-4

Page 55

FLUE

BOLTS

(4)

EXHAUST

MANIFOLD

UNIT FRAME

MAINTENANCE

7.9 PLACING THE BOILER BACK IN

SERVICE AFTER A PROLONGED SHUTDOWN

After a prolonged shutdo wn (one year or more), the following procedures must be followed:

1. Review installation requirements inc luded in Chapter 2.

CONDENSATE

DRAIN

HOSE

CLAMP

1" I.D.

HOSE

TRAP

TO FLOOR

DRAIN

Figure 7-5

Exhaust Manifold Condensate Trap &

Drain

7.8 SHUTTING THE BOILER DOWN FOR AN EXTENDED PERIOD OF TIME

If the boiler is to be taken out of s ervice for an extended period of tim e (one year or more), the following instructions must be followed.

2. Inspect all piping and connections to the unit.

3. Inspect exhaust vent, air duct (if applicable).

4. Perform initial startup per Chapter 4.

5. Perform safety device testing and the scheduled maintenance procedures per Chapters 6 and 7 of this manual.

1. Set ON/OFF s witch on the f ront panel to the OFF position to shut down the boiler’s operating controls.

2. Dis c onnect AC po wer fr om the unit.

3. Close the water supply and return valv es to isolate boiler.

4. Close external gas supply valve.

5. O pen relief valve to vent water pressure.

7-5

Page 56

Page 57

TROUBLESHOOTING

Chapter 8- TROUBLESHOOTING GUIDE

8.1 INTRODUCTION

This troubleshooting guide is intended to aid service/maintenance personnel in isolating the cause of a fault in a Benchmark 3.0 Boiler. The troubleshooting procedures contained herein are presented in tabular form on the following pages. These tables are comprised of three columns labeled: Fault Indication, Probable Cause and Corrective Action. The numbered items in the Probable Cause and Corrective Action columns correspond to each other. For example, Probable Cause No. 1 corresponds to Corrective Action No. 1, etc.

When a fault occurs in the Benchmark Boiler, proceed as follows to isolate and correct the fault:

1. Observe the fault messages displayed in the Control Box display.

2. Refer to the Fault Indication column in Troubleshooting Table 8-1 which follows and locate the Fault that best describes the existing conditions.

3. Proceed to the Probable Cause column and start with the first item (1) listed for the Fault Indication.

4. Perform the checks and procedures listed in the Corrective Action column for the first Probable Cause candidate.

5. Continue checking each additional Probable Cause for the existing fault until the fault is corrected.

6. Paragraph 8.2 and Table 8-2 contain additional troubleshooting information which may apply when no fault message is displayed.

7. If the fault cannot be corrected using the information provided in the Troubleshooting Tables, contact your local AERCO Representative.

8-1

Page 58

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

AIRFLOW FAULT

DURING IGNITION

1. Blower stopped running due to thermal or current overload

2. Blocked Blower inlet or inlet ductwork

3. Blocked Blower proof switch

4. Blocked blocked-air inlet switch

5. Defective Blower proof switch

6. Defective blocked-air inlet switch

7. Loose temperature transmitter to VFD’s analog input wire connection

8. Loose temperature sensor to temperature transmitter wire connection.

9. Defective temperature transmitter

10. Defective temperature sensor

11. Loose wire connection between the 420 mA signal from I/O box to VFD analog input

12. Defective I/O box

13. W rong 4-20 mA output selection on the control box

14. Defective air-fuel valve potentiometer

15. Defective or missing VFD’s logic stick

16. Defective program on the logic stick or Defective VFD.

1. Check combustion blower for signs of excessive heat or high current drain that may trip thermal or current overload devices.

2. Inspect the inlet to the combustion blower including any ductwork leading up to the combustion blower for signs of blockage.

3. Remove the Blower proof switch and inspect for signs of blockage, clean or replace as necessary.

4. Remove the blocked-air inlet switch and inspect for signs of blockage, clean or replace as necessary.

5. Measure the Blower proof switch for continuity with the combustion blower running. If there is an erratic resistance reading or the resistance reading is greater than zero ohms, replace the switch.

6. Measure the blocked-air inlet switch for continuity with the combustion blower running. If there is an erratic resistance reading or the resistance reading is greater than zero ohms, replace the switch.

7. Check the actual inlet air temperature and measure voltage at temperature transmitter and VFD analog input. Verify that the voltage conforms to Table 8-3 for the inlet air temperature.

8. Refer to CORRECTIVE ACTION 7 and verify that the resistance conforms to Table 8-3.

9. See CORRECTIVE ACTION 7.

10. See CORRECTIVE ACTION 8.

11. Measure amperage at the I/O box output and VFD analog input, 4mA equates to 0% fire rate and 20 mA equates to 100% fire rate

12. See CORRECTIVE ACTION 11.

13. Check C-More configuration menu, mA OUT – Fire Rate should be selected

14. Check air fuel valve position at 0%, 50% and 100% fire rates,

the position on the c-more barograph should match the valve

15. Confirm that the logic stick is securely mounted on the VFD

16. Check the following VFD parameters: Max Hz = 67, Min Hz = 0,

parameter 59 & 60 should be set to 2.

-2

Page 59

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

AIRFLOW FAULT

DURING PURGE

AIRFLOW FAULT

DURING RUN

1. Blower not running or running too slow

2. Defective Air Flow Switch

3. Blocked Air flow Switch

4. Blocked Blower inlet or inlet ductwork.

5. No voltage to switch from control box.

PROBABLE CAUSES

6. for AIRFLOW FAULT DURING IGNITION applies for this fault

1. Blower stopped running due to thermal or current overload

2. Blocked Blower inlet or inlet ductwork

3. Blocked airflow switch

4. Defective airflow switch

5. Combustion oscillations

PROBABLE CAUSES

6. for AIRFLOW FAULT DURING IGNITION applies for this fault

from 3 to 16

1. Start the unit. If the blower does not run check the blower solid state relay for input and output voltage. If the relay is okay, check the blower.

2. Start the unit. If the blower runs, check the airflow switch for continuity. Replace the switch if there is no continuity.

3. Remove the air flow switch and inspect for signs of blockage, clean or replace as necessary.

4. Inspect the inlet to the combustion blower including any ductwork leading up to the combustion blower for signs of blockage.

5. Measure for 24 VAC during start sequence from each side of the switch to ground. If 24VAC is not present refer to qualified service personnel.

6. See

1. Check combustion blower for signs of excessive heat or high

2. Inspect the inlet to the combustion blower including any ductwork

3. Remove the airflow switch and inspect for signs of blockage,

4. Measure the airflow switch for continuity with the combustion

5. Run unit to full fire. If the unit rumbles or runs rough, perform

CORRECTIVE ACTION

FAULT DURING IGNITION

current draw that may trip thermal or current overload devices.

leading up to the combustion blower for signs of blockage.

clean or replace as necessary.

blower running. If there is an erratic resistance reading or the resistance reading is greater than zero ohms, replace the switch.

combustion calibration.

PROBABLE CAUSES

DURING IGNITION applies for this fault

from 3 to 16 for AIRFLOW FAULT

from 3 to 16 for AIRFLOW

-3

Page 60

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION

DELAYED

INTERLOCK OPEN

DIRECT DRIVE SIGNAL FAULT

FLAME LOSS

DURING IGN

1. Delayed Interlock Jumper not installed or removed.

2. Device proving switch hooked to interlocks is not closed

1. Direct drive signal is not present: Not yet installed. Wrong polarity. Signal defective at source. Broken or loose wiring.

2. Signal is not isolated (floating).

3. Control Box signal type selection switches not set for correct signal type (voltage or current).

1. Burner Ground Screw not installed or loose.

2. Worn flame detector

3. No spark from Spark Plug

4. Defective Ignition Transformer

5. Defective Ignition/Stepper (IGST) Board

6. Defective SSOV

PROBABLE CAUSES

1. Check for a jumper properly installed across the delayed interlock terminals in the I/O box.

2. If there are 2 external wires on these terminals, check to see if an end switch for a device such as a pump, louver, etc. is tied these interlocks. Ensure that the device and or its end switch are functional. (jumper may be temporarily installed to test interlock)

1. Check I/O Box to ensure signal is hooked up. Hook up if not installed. If installed, check polarity. Measure signal level. Check continuity of wiring between source and boiler.

2. Check signal at source to ensure it is isolated.

3. Check DIP switch on PMC board to ensure it is set correctly for the type of signal being sent. Check control signal type set in Configuration Menu.

1. Inspect and install/retighten Burner Ground Screw.

2. Remove and inspect the flame detector for signs of wear. Replace if necessary.

3. Close the internal gas valve in the boiler. Install and arc a spark ignitor outside the unit.

4. If there is no spark, check for 120VAC at the primary side to the ignition transformer during the ignition cycle.

5. If 120VAC is not present, the IGST Board in the Control Box may be defective. Refer fault to qualified service personnel.

6. While externally arcing the spark ignitor, observe the open/close indicator in the Safety Shut-Off Valve to ensure it is opening. If the valve does not open, check for 120VAC at the valves input terminals. If 120VAC is not present, the IGST board in the Control Box may be defective. Refer fault to qualified service personnel.

CORRECTIVE ACTION

-4

Page 61

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION

(continued) 7. Defective Differential Pressure

FLAME LOSS

DURING RUN

HEAT DEMAND

FAILURE

HIGH EXHAUST TEMPERATURE

HIGH GAS

PRESSURE

8. Carbon or other debris on Burner

1. Worn Flame Detector or cracked

2. Defective Differential Regulator.

3. Poor combustion calibration.

4. Debris on burner.

5. Blocked condensate drain.

1. The Heat Demand Relays on the

2. Relay is activated when not in

1. Defective exhaust sensor.

2. Carboned heat exchanger due to

1. Incorrect supply gas pressure.

2. Defective SSOV Supply Regulator.

PROBABLE CAUSES

Regulator

ceramic.

Ignition/Stepper board failed to activate when commanded

Demand

incorrect combustion calibration

7. Check gas pressure readings using gauge or manometer into and out of the Air/Fuel Valve to ensure gas is getting to the burner.

8. Remove the burner and inspect for any carbon or debris. Clean and reinstall

1. Remove and inspect the Flame Detector for signs of wear or cracked ceramic. Replace if necessary.

2. Check gas pressure readings using a gauge or manometer into and out of the Air/Fuel Valve to ensure that the gas pressure into and out of the valve is correct.

3. Check combustion calibration. Adjust as necessary.

4. Remove the burner and inspect for any carbon or debris. Clean and reinstall.

5. Remove blockage in condensate drain.

1. Press CLEAR button and restart the unit. If the fault persists, replace Ignition/Stepper (IGST) Board.

2. Defective relay. Replace IGST Board.

1. Measure the actual exhaust temperature and continuity of the exhaust sensor. If the exhaust temperature is less than 475 and the exhaust sensor shows continuity replace the sensor.

2. If exhaust temperature is greater than 500 combustion calibration. Calibrate or repair as necessary.

1. Check to ensure gas pressure at inlet of SSOV is 2 psig maximum.

2. If gas supply pressure downstream of SSOV cannot be lowered, to 1.8” W.C. (see para. 4.3, step 10), the SSOV Supply Regulator may be defective.

CORRECTIVE ACTION

F, check

-5

Page 62

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION

continued 3. Defective High Gas Pressure Switch

HIGH WATER TEMP

SWITCH OPEN

HIGH WATER

TEMPERATURE

IGN BOARD

COMM FAULT

4. Gas pressure snubber not installed.

1. Faulty Water temperature switch.

2. Incorrect PID settings.

3. Faulty shell temperature sensor.

4. Unit in Manual mode

5. Unit setpoint is greater than Over

6. Boiler Management System PID or

7. No interlock to boiler or BMS to

8. System flow rate changes are

1. See HIGH WATER TEMPERATURE

2. Temp HI Limit setting is too low.

1. Communication fault has occurred

PROBABLE CAUSES

Temperature Switch setpoint.

other settings not correctly setup.

disable boiler(s) in event that system pumps have failed.

occurring faster than boilers can respond.

SWITCH OPEN.

between the PMC board and Ignition/Stepper (IGST) board

3. Remove the leads from the high gas pressure switch and measure continuity across the common and normally closed terminals with the unit not firing. Replace the switch if it does not show continuity.

4. See Figure 8-1. Ensure that the gas pressure snubber is installed at the high gas pressure switch.

1. Test the temperature switch to insure it trips at its actual water temperature setting.

2. Check PID settings against Menu Default settings in the Appendix. If the settings have been changed, record the current readings then reset them to the default values.

3. Using the resistance charts in the Appendix C, Measure the resistance of Shell sensor and BTU sensor at a known water temperature.

4. If unit is in Manual Mode switch to Auto Mode.

5. Check setpoint of unit and setpoint of Temperature Switch; Ensure that the temperature switch is set higher than the unit’s setpoint.

6. Check the BMS for changes to PID default values, correct as necessary.

7. If system pump is controlled by Energy Management System other than BMS or pumps are individually controlled by boiler, check to see if there are flow switches interlocked to the BMS or boiler.

8. If the system is a variable flow system, monitor system flow changes to ensure that the rate of flow change is not faster than what the boilers can respond to.

1. See HIGH WATER TEMPERATURE SWITCH OPEN.

2. Check Temp HI Limit setting.

1. Press CLEAR button and restart unit. If fault persists, contact qualified Service Personnel.

CORRECTIVE ACTION

8-6

Page 63

TROUBLESHOOTING

FAULT INDICATION

IGN SWTCH CLOSED

DURING PURGE

IGN SWTCH OPEN

DURING IGNITION

INTERLOCK

OPEN

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

1. Air/Fuel Valve not rotating

2. Defective or shorted switch

3. Switch wired incorrectly

4. Defective Power Supply Board or fuse

5. Defective IGST Board

1. Air/Fuel Valve not rotating to ignition position.

2. Defective ignition switch

3. Defective Power Supply Board or fuse

4. Defective IGST Board

1. Interlock jumper not installed or removed

2. Energy Management System does not have boiler enabled.

PROBABLE CAUSES

1. Start the unit. The Air/Fuel Valve should rotate to the purge (open) position. If the valve does not rotate at all or does not rotate fully open, check the Air/Fuel Valve calibration. If calibration is okay, the problem may be in the Air-Fuel Valve or the Control Box. Refer to qualified service personnel

2. . If the Air/Fuel Valve does rotate to purge, check the ignition switch for continuity between the N.O. and COM terminals. If the switch shows continuity when not in contact with the cam replace the switch.

3. Check to ensure that the switch is wired correctly (correct wire numbers on the normally open terminals). If the switch is wired correctly, replace the switch

4. Check DS1 & DS2 LEDs on Power Supply Board. If they are not steady ON, replace Power Supply Board.

5. Check “Heartbeat” LED DS1 and verify it is blinking ON & OFF every second. If not, replace IGST Board

1. Start the unit. The Air/Fuel Valve should rotate to the purge (open) position, then back to ignition position (towards closed) during the ignition cycle. If the valve does not rotate back to the ignition position, check the Air/Fuel Valve calibration. If calibration is okay, the problem may be in the Air/Fuel Valve or the Control Box. Refer fault to qualified service personnel.

2. If the Air/Fuel Valve does rotate to the ignition position, check the ignition position switch for continuity between the N.O. and COM terminals when in contact with the cam.

3. Check DS1 & DS2 LEDs on Power Supply Board. If they are not steady ON, replace Power Supply Board.

4. Check “Heartbeat” LED DS1 and verify it is blinking ON & OFF every second. If not, replace IGST Board.

1. Check for a jumper properly installed across the interlock terminals in the I/O box

2. If there are two external wires on these terminals check any Energy Management system to see if they have the units disabled (a jumper may be temporarily installed to see if the interlock circuit is functioning).

CORRECTIVE ACTION

8-7

Page 64

TROUBLESHOOTING

FAULT INDICATION PROBABLE CAUSES

continued 3. Device proving switch hooked to

LINE VOLTAGE

OUT OF PHASE

LOW GAS

PRESSURE

LOW WATER

LEVEL

MODBUS COMM

FAULT

PRG SWTCH CLOSED

DURING IGNITION

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

interlocks is not closed.

1. Line and Neutral switched in AC Power Box.

2. Incorrect power supply transformer wiring.

1. Incorrect supply gas pressure.

2. Defective Low Pressure Gas Switch

1. Insufficient water level in system

2. Defective water level circuitry.

3. Defective water level probe.

1. Boiler not seeing information from modbus network

1. A/F Valve rotated open to purge and did not rotate to ignition position

2. Defective or shorted switch.

3. Switch wired incorrectly.

4. Defective Power Supply Board or fuse

5. Defective IGST Board

3. Check that proving switch for any device hooked to the interlock circuit is closing and that the device is operational.

1. Check hot and neutral in AC Power Box to ensure they are not reversed

2. Check transformer wiring, in AC Power Box, against the power box transformer wiring diagram to ensure it is wired correctly

1. Measure gas pressure upstream of the supply gas regulator with the unit firing. Ensure it is between 4” W.C. and 2 psig (see para.

2.7.1).

2. Measure gas pressure at the low gas pressure switch. If it is greater than 2.6” W.C., measure continuity across the switch and replace if necessary.

1. Check system for sufficient water level.

2. Test water level circuitry using the Control Box front panel LOW WATER TEST and RESET buttons. Replace water level circuitry if it does not respond.

3. Check continuity of probe end to the shell, change probe if there is no continuity.

1. Check network connections. If fault persists, contact qualified Service Personnel.

2. If the Air/Fuel Valve does rotate to the ignition position, check the purge switch for continuity between the N.O. and COM terminals. If the switch shows continuity when not in contact with the cam, check to ensure that the switch is wired correctly (correct wire numbers on the normally open terminals).

3. If the switch is wired correctly, replace the switch.

4. Check DS1 & DS2 LEDs on Power Supply Board. If they are not steady ON, replace Power Supply Board.

5. Check “Heartbeat” LED DS1 and verify it is blinking ON & OFF every second. If not, replace IGST Board.

CORRECTIVE ACTION

8-8

Page 65

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

PRG SWTCH OPEN

DURING PURGE

OUTDOOR TEMP

SENSOR FAULT

REMOTE SETPT

SIGNAL FAULT

RESIDUAL

FLAME

1. Defective purge switch.

2. No voltage present at switch.

3. Switch wired incorrectly.

4. Defective Power Supply Board or fuse

5. Defective IGST Board

1. Loose or broken wiring.

2. Defective Sensor.

3. Incorrect Sensor.

1. Remote setpoint signal not present: Not yet installed. Wrong polarity. Signal defective at source. Broken or loose wiring.

2. Signal is not isolated (floating) if 4 to 20 mA.

3. Control Box signal type selection switches not set for correct signal type (voltage or current).

1. SSOV not fully closed. 1. Check open/close indicator window of Safety Shut-Off Valve

1. If the air-fuel valve does rotate, check the purge switch for continuity when closing. Replace switch if continuity does not exist.

2. Measure for 24 VAC from each side of the switch to ground. If 24VAC is not present, refer fault to qualified service personnel.

3. Check to ensure that the switch is wired correctly (correct wire numbers on the normally open terminals).

4. Check DS1 & DS2 LEDs on Power Supply Board. If they are not steady ON, replace Power Supply Board.

5. Check “Heartbeat” LED DS1 and verify it is blinking ON & OFF every second. If not, replace IGST Board.

1. Inspect Outdoor Temperature sensor for loose or broken wiring.

2. Check resistance of sensor to determine if it is within specification.

3. Ensure that the correct sensor is installed.

1. Check I/O Box to ensure signal is hooked up. Hook up if not installed. If installed, check polarity. Measure signal level. Check continuity of wiring between source and boiler.

2. Check signal at source to ensure it is isolated.

3. Check DIP switch on PMC board to ensure it is set correctly for the type of signal being sent. Check control signal type set in Configuration Menu.

(SSOV) and ensure that the SSOV is fully closed. If not fully closed, replace the valve and or actuator.

Close gas shut-off valve downstream of SSOV. Install a manometer or gauge in a gas test port between the SSOV and the gas shut off valve. If a gas pressure reading is observed replace the SSOV valve and or actuator.

8-9

Page 66

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

(continued) 2. Defective Flame Detector

SSOV FAULT

DURING PURGE

SSOV FAULT

DURING RUN

SSOV RELAY

FAILURE

SSOV

SWITCH OPEN

STEPPER MOTOR

FAILURE

See SSOV SWITCH OPEN

1. SSOV switch closed for 15 seconds during run.

1. SSOV relay failed on board. 1. Press CLEAR button and restart unit. If fault persists, replace

1. Actuator not allowing for full closure of gas valve

2. SSOV powered when it should not be

3. Defective Switch or Actuator

4. Incorrectly wired switch.

1. Air/Fuel Valve out of calibration.

2. Air/Fuel Valve unplugged.

3. Loose wiring connection to the stepper motor.

4. Defective Air/Fuel Valve stepper motor.

5. Defective Power Supply Board or fuse

6. Defective IGST Board

2. Replace Flame Detector.

1. Replace or adjust microswitch in SSOV actuator. If fault persists, replace actuator.

Ignition/Stepper (IGST) Board.

1. Observe operation of the Safety Shut-Off Valve (SSOV) through indicator on the Valve actuator and ensure that the valve is fully and not partially closing.

2. If the SSOV never closes, it may be powered continuously. Close the gas supply and remove power from the unit. Refer fault to qualified service personnel.

3. Remove the electrical cover from the SSOV and check switch continuity. If the switch does not show continuity with the gas valve closed, either adjust or replace the switch or actuator.

4. Ensure that the SSOV Proof of Closure switch is correctly wired.

1. Refer to GF-112 and perform Stepper Test (para. 6.3.5) to ensure stepper motor rotates properly between the 0% (fully closed) and 100% (fully open) positions. Verify that the FIRE RATE bargraph and the dial on the Air/Fuel Valve track each other to indicate proper operation. If operation is not correct, perform the Stepper Feedback Calibration (GF-112, para. 6.2.1).

2. Check that the Air/Fuel Valve is connected to the Control Box.

3. .Inspect for loose connections between the Air/Fuel Valve motor and the wiring harness.

4. Replace stepper motor.

5. Check DS1 & DS2 LEDs on Power Supply Board. If they are not steady ON, replace Power Supply Board.

6. Check “Heartbeat” LED DS1 and verify it is blinking ON & OFF every second. If not, replace IGST Board.

-10

Page 67

TROUBLESHOOTING

8.2 ADDITIONAL FAULTS WITHOUT SPECIFIC FAULT MESSAGES

Refer to Table 8-2 to troubleshoot faults which may occur without a specific fault message being displayed.

TABLE 8-2. BOILER TROUBLESHOOTING WITH NO FAULT MESSAGE DISPLAYED

OBSERVED INCIDENT PROBABLE CAUSES CORRECTIVE ACTION

Hard Light-Off 1. Staged Ignition Ball Valve closed.

2. Clogged/damaged Gas Injector (Figure 8-2).

3. Defective Staged Ignition Solenoid (Figure 8-2)

Fluctuating Gas Pressure 1. Gas pressure going into unit is

fluctuating.

2. Damping Orifice not installed.

Air/Fuel Valve “hunting” at 80%

Firing Rate

1. IGST and Power Supply Boards in Control Box are outdated.

1. Open the 1/4” Ball Valve downstream of the SSOV (Fig. 8-1).

2. Remove and inspect Gas Injector to ensure it is not clogged or damaged.

3. Close the 2” and the 1/4” Ball Valve downstream of the SSOV (Fig. 8-1). Start the unit and listen for a “clicking” sound that the Staged Ignition Solenoid makes during Ignition Trial. If “clicking” sound is not heard after 2 or 3 attempts, replace the Staged Ignition Solenoid.

1. Stabilize gas pressure going into unit. If necessary, troubleshoot Building Supply Regulator.

2. Check to ensure that the Damping Orifice is installed in the downstream SSOV/Regulator Actuator (Figure 8-3).

1. Check to ensure that the IGST and Power Supply Boards are Rev. E or higher.

8-11

Page 68

TROUBLESHOOTING

Figure 8-2

Staged Ignition Solenoid Location

8-12

Figure 8-1

High Pressure Gas Switch & Snubber Locations

Figure 8-3

Damping Orifice Location

Page 69

TROUBLESHOOTING

Table 8-3

BMK 3.0 LN (3.3 KΩ) Temperature Sensor and Temperature

Transmitter Outputs

TEMP

ºC

-40 -40 111177 0.289 28 82.4 2915 6.16

-30 -22 58443 0.523 29 84.2 2787 6.31

-20 -4 32814 0.904 30 86 2659 6.470

-10 14 18200 1.560 31 87.8 2549 6.610

-5 23 13972 1.972 32 89.6 2443 6.760 0 32 10775 2.459 33 91.4 2343 6.900 1 33.8 10240 2.564 34 93.2 2247 7.040 2 35.6 9735 2.680 35 95 2156 7.180 3 37.4 9256 2.791 36 96.8 2068 7.320 4 39.2 8806 2.906 37 98.6 1984 7.460 5 41 8380 3.022 38 100.4 1905 7.600 6 42.8 7977 3.143 39 102.2 1830 7.730 7 44.6 7595 3.267 40 104 1758 7.860 8 46.4 7234 3.387 41 105.8 1688 8.000 9 48.2 6891 3.514 42 107.6 1622 8.130

10 50 6566 3.643 43 109.4 1559 8.250 11 51.8 6260 3.772 44 111.2 1499 8.490 12 53.6 5969 3.900 45 113 1441 8.510 13 55.4 5692 4.040 46 114.8 1386 8.630 14 57.2 5432 4.170 47 116.6 1334 8.750 15 59 5184 4.310 48 118.4 1283 8.960 16 60.8 4972 4.440 49 120.2 1234 8.980 17 62.6 4759 4.570 50 122 1189 9.100 18 64.4 4547 4.710 51 123.8 1145 9.210 19 66.2 4334 4.860 52 125.6 1102 9.320 20 68 4122 5.020 53 127.4 1061 9.430 21 69.8 3958 5.150 54 129.2 1023 9.530 22 71.6 3793 5.290 55 131 986 9.640 23 73.4 3629 5.520 56 132.8 950 9.740 24 75.2 3464 5.580 57 134.6 916 9.840 25 77 3300 5.740 58 136.4 883 9.920 26 78.8 3172 5.870 59 138.2 852 10.030 27 80.6 3044 6.010 60 140 821 10.120

TEMP

ºF

UA33

Resistance

Ohm

Volts

outputs

UA33

TEMP

ºC

TEMP

ºF

UA33

Resistance

Ohm

Volts

outputs

UA33

8-13

Page 70

Page 71

APPENDIX A - BOILER MENU ITEM DESCRIPTIONS

MENU LEVEL & OPTION DESCRIPTION

OPERATING MENU

Active Setpoint This is the setpoint temperature to which the

control is set when operating in the Constant Setpoint, Remote Setpoint or Outdoor Reset Mode. When in the Constant Setpoint Mode, this value is equal to the Internal Setpoint setting in the Configuration Menu. When in the Remote Setpoint Mode, this value is the setpoint equivalent to the remote analog signal supplied to the unit. When in the Outdoor Reset Mode, this is the derived value from the charts in Appendix D.

Aux Temp For monitoring purposes only

APPENDIX A

Outdoor Temp Displayed only if outdoor sensor is installed and

enabled.

Fire Rate In Desired input fire rate. This would normally be the

same as the fire rate shown on the bar-graph (fire rate out) when the boiler is operating.

Flame Strength Displays flame strength from 0% to 100%.

Run Cycles Displays the total number of run cycles from 0 to

999,999.

Run Hours Displays total run time of unit in hours from 0 to

9,999,999.

Fault Log Displays information on the last 9 faults.

A-1

Page 72

APPENDIX A

APPENDIX A - BOILER MENU ITEM DESCRIPTIONS - Continued

MENU LEVEL & OPTION DESCRIPTION

SETUP MENU

Password Allows password to be entered.

Once the valid password (159) is entered, options in the Setup, Configuration and Tuning Menus can be modified.

Language Permits selection of English, Spanish or French for

displayed messages. Default is English.

Time Displays time from 12:00 am to 11:59 pm.

Date Displays dates from 01/01/00 to 12/31/99

Unit of Temp Permits selection of temperature displays in degrees

Fahrenheit (°F) or degrees Celsius (°C). Default is °F.

Comm Address For RS-485 communications (0 to 127). Default

address is 0. RS-232 should have its own (programmable) password.

Baud Rate Allows communications Baud Rate to be set (2400

to 19.2K). Default is 9600.

Software Version Identifies the current software version of the control

box (Ver 0.0 to Ver 9.9).

CONFIGURATION MENU

Internal Setpoint Allows internal setpoint to be set . Default is 130°F.

Unit Type Allows selection of Boiler or Water Heater.

Unit Size Sets unit size from 0.5 to 3.0 MBTUs. Default is 1.0

MBTU.

Boiler Mode It allows selection of: Constant Setpoint, Remote

Setpoint, Direct Drive, Combination, or Outdoor Reset Mode. Default is Constant Setpoint Mode.

Remote Signal Used to set the type of external signal which will be

used when operating in the Remote Setpoint, Direct Drive or Combination Mode. The factory default is 4-20 mA/1-5V.

Bldg Ref Temp

Allows the building reference temperature to be set when operating a boiler in the Outdoor Reset Mode. Default is 70°F.

A-2

Page 73

APPENDIX A

APPENDIX A - BOILER MENU ITEM DESCRIPTIONS - Continued

MENU LEVEL & OPTION DESCRIPTION

Reset Ratio Permits setting of Reset Ratio when operating boiler

in the Outdoor Reset Mode. Reset Ratio is adjustable from 0.1 to 9.9. Default is 1.2.

Outdoor Sensor Allows outdoor sensor function to be enabled or

disabled. Default is disabled.

System Start Tmp If outdoor sensor is enabled, this menu item allows

the system start temperature to be set from 30 to 100°F. Default is 60°F.

Setpoint Lo Limit Used to set the minimum allowable setpoint (40°F to

Setpoint Hi Limit). Default is 60°F

Setpoint Hi Limit Used to set the maximum allowable setpoint

(Setpoint Lo Limit to 240°F). Default is 200°F.

Temp Hi Limit This is the maximum allowable outlet temperature

(40 to 240°F). Any temperature above this setting will turn off the unit. The temperature must then drop 5° below this setting to allow the unit to run. Default Hi Limit is 210°F.

Max Fire Rate Sets the maximum allowable fire rate for the unit

(40% to 100%). Default is 100%.

Pump Delay Timer Specifies the amount of time (0 to 30 min.) to keep

the pump running after the unit turns off. Default is zero.

Aux Start On Dly Specifies the amount of time to wait (0 to 120 sec.)

between activating the Aux Relay (due to a demand) and checking the pre-purge string to start the boiler. Default is 0 sec.

Failsafe Mode Allows the Failsafe mode to be set to either

Constant Setpoint or Shutdown. Default is Shutdown.

mA Output Must be set to Fire Rate Out for Benchmark 3.0LN.

Lo Fire Timer Specifies how long (2 to 600 sec.) to remain in the

low fire position after ignition, before going to the desired output. Default is 2 sec.

A-3

Page 74

APPENDIX A

APPENDIX A - BOILER MENU ITEM DESCRIPTIONS - Continued

MENU LEVEL & OPTION DESCRIPTION

TUNING MENU

Prop Band Generates a fire rate based on the error that exists

between the setpoint temperature and the actual outlet temperature. If the actual error is less than the proportional band setting (1 to 120°F), the fire rate will be less than 100%. If the error is equal to or greater than the proportional band setting, the fire rate will be 100%.

Integral Gain This sets the fraction of the output, due to setpoint

error, to add or subtract from the output each minute to move towards the setpoint. Gain is adjustable from 0.00 to 1.00 (Default is 0.10).

Derivative Time This value (0.0 to 20.0 min.) responds to the rate of

change of the setpoint error. This is the time that this action advances the output.

Reset Defaults? Allows Tuning Menu options to be reset to their

Factory Default values.

A-4

Page 75

APPENDIX B - STARTUP, STATUS AND FAULT MESSAGES

MESSAGE DESCRIPTION

DISABLED

HH:MM pm MM/DD/YY

STANDBY Displayed when ON/OFF switch is in the ON position, but

DEMAND DELAY

XX sec

PURGING

XX sec

IGNITION TRIAL

XX sec

FLAME PROVEN

WARMUP

XX sec

WAIT Prompts the operator to wait.

APPENDIX B

TABLE B-1. STARTUP AND STATUS MESSAGES

Displayed if ON/OFF switch is set to OFF. The display also shows the time and date that the unit was disabled.

there is no demand for heat. The time and date are also displayed. Displayed if Demand Delay is active.

Displayed during the purge cycle during startup. The duration of the purge cycle counts up in seconds. Displayed during ignition trial of startup sequence. The duration of cycle counts up in seconds. Displayed after flame has been detected for a period of 2 seconds. Initially, the flame strength is shown in %. After 5 seconds has elapsed, the time and date are shown in place of flame strength. Displayed for 2 minutes during the initial warmup only.

B-1

Page 76

APPENDIX B

FAULT MESSAGE FAULT DESCRIPTION

HIGH WATER TEMP

SWITCH OPEN

LOW WATER

LEVEL

LOW GAS

PRESSURE

HIGH GAS

PRESSURE

INTERLOCK

OPEN

DELAYED

INTERLOCK OPEN

AIRFLOW FAULT

DURING PURGE

PRG SWTCH OPEN

DURING PURGE

IGN SWTCH OPEN

DURING IGNITION

IGN SWTCH CLOSED

DURING PURGE

PRG SWTCH CLOSED

DURING IGNITION

AIRFLOW FAULT

DURING IGN

AIRFLOW FAULT

DURING RUN

SSOV

SWITCH OPEN

SSOV FAULT

DURING PURGE

SSOV FAULT

DURING IGN

SSOV FAULT DURING RUN SSOV RELAY

FAILURE

FLAME LOSS

DURING IGN FLAME LOSS DURING RUN

HIGH EXHAUST TEMPERATURE

LOSS OF POWER

TABLE B-2. FAULT MESSAGES

The High Water Temperature Limit Switch is open.

The Water Level Control board is indicating low water level.

The Low Gas Pressure Limit Switch is open.

The High Gas Pressure Limit Switch is open.

The Remote Interlock is open.

The Delayed Interlock is open.

The Blower Proof Switch opened during purge, or air inlet is blocked. The Purge Position Limit switch on the air/fuel valve opened during purge. The Ignition Position Limit switch on the air/fuel valve opened during ignition. The Ignition Position Limit switch on the air/fuel valve closed during purge. The Purge Position Limit switch on the air/fuel valve closed during ignition. The Blower Proof Switch opened during ignition.

The Blower Proof Switch opened during run.

The SSOV switch opened during standby.

The SSOV switch opened during purge.

The SSOV switch closed or failed to open during ignition.

The SSOV switch closed for more than 15 seconds during run. A failure has been detected in one of the relays that control the SSOV. The Flame signal was not seen during ignition or lost within 5 seconds after ignition. The Flame signal was lost during run.

The High Exhaust Temperature Limit Switch is closed.

A power loss had occurred. The time and date when power was restored is displayed.

B-2

Page 77

APPENDIX B

TABLE B-2. FAULT MESSAGES - Continued

FAULT MESSAGE FAULT DESCRIPTION

RESIDUAL

FLAME

HEAT DEMAND

FAILURE

IGN BOARD

COMM FAULT DIRECT DRIVE SIGNAL FAULT

REMOTE SETPT

SIGNAL FAULT

OUTDOOR TEMP

SENSOR FAULT

OUTLET TEMP

SENSOR FAULT

FFWD TEMP

SENSOR FAULT

HIGH WATER

TEMPERATURE

LINE VOLTAGE

OUT OF PHASE

STEPPER MOTOR

FAILURE

NETWORK COMM

FAULT

The Flame signal was seen for more than 60 seconds during standby. The Heat Demand Relays on the Ignition board failed to activate when commanded. A communication fault has occurred between the PMC board and Ignition board. The direct drive signal is not present or is out of range.

The remote setpoint signal is not present or is out of range.

The temperature measured by the Outdoor Air Sensor is out of range. The temperature measured by the Outlet Sensor is out of range. The temperature measured by the FFWD Sensor is out of range. The temperature measured by the Outlet Sensor exceeded the Temp Hi Limit setting. The High AC voltage is out of phase from the low AC voltage.

The stepper motor failed to move the valve to the desired position. The RS-485 network information is not present or is corrupted.

B-3

Page 78

Page 79

TEMPERATURE SENSOR RESISTANCE CHART

(BALCO)

TEMPERATURE SENSOR AERCO PART NO. 123449

R = RESISTANCE (OHMS) T = TEMPERATURE (°F)

R=.00161T^2+1.961T+854.841

APPENDIX C

TEMP (°F) RES. (OHMS)

-40 779.0

-30 797.5

-20 816.3

-10 835.4 0 854.8

10 874.6 20 894.7 30 915.1 40 935.9 50 956.9 60 978.3 70 1000.0 80 1022.0

90 1044.4 100 1067.0 110 1090.0 120 1113.3 130 1137.0 140 1160.9 150 1185.2 160 1209.5 170 1234.7 180 1260.0 190 1285.6 200 1311.4 210 1337.7 220 1364.2 230 1391.0 240 1418.2 250 1445.7

C-1

Page 80

Page 81

Air

Temp

50F 45F 40F 35F 30F 25F 20F 15F 10F

5F 0F

-5F

-10F

-15F

-20F

Air

Temp

60F 55F 50F 45F 40F 35F 30F 25F 20F 15F 10F

5F 0F

-5F

-10F

-15F

-20F

APPENDIX D

APPENDIX D. - INDOOR/OUTDOOR RESET RATIO CHARTS

Table D-1. Header Temperature for a Building Reference Temperature of 50F

RESET RATIO

0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

50 50 50 50 50 50 50 50 50 50 53 54 55 56 57 58 59 60 60 62 56 58 60 62 64 66 68 70 72 74 59 62 65 68 71 74 77 80 83 86 62 66 70 74 78 82 86 90 94 98 65 70 75 80 85 90 95 100 105 110 68 74 80 86 92 98 104 110 116 122 71 78 85 92 99 106 113 120 127 134 74 82 90 98 106 114 122 130 138 146 77 86 95 104 113 122 131 140 149 158 80 90 100 110 120 130 140 150 160 170 83 94 105 116 127 138 149 160 171 182 86 98 110 122 134 146 158 170 182 194 89 102 115 128 141 154 167 180 193 206 92 106 120 134 148 162 176 190 204 218

Table D-2. Header Temperature for a Building Reference Temperatrure of 60F

RESET RATIO

0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

60 60 60 60 60 60 60 60 60 60 63 64 65 66 67 68 69 70 71 72 66 68 70 72 74 76 78 80 82 84 69 72 75 78 81 84 87 90 93 96 72 76 80 84 88 92 96 100 104 108 75 80 85 90 95 100 105 110 115 120 78 84 90 96 102 108 114 120 126 132 81 88 95 102 109 116 123 130 137 144 84 92 100 108 116 124 132 140 148 156 87 96 105 114 123 132 141 150 159 168 90 100 110 120 130 140 150 160 170 180 93 104 115 126 137 148 159 170 181 192 96 108 120 132 144 156 168 180 192 204

99 112 125 138 151 164 177 190 203 216 102 116 130 144 158 172 186 200 214 105 120 135 150 165 180 195 210 108 124 140 156 172 188 204

D-1

Page 82

APPENDIX D

Table D-3. Header Temperature for a Building Reference Temperature of 65F

Air

Temp

65 60 55 50 45 40 35 30 25 20 15 10

5 0

-5

-10

-15

-20

Air

Temp

70F 65F 60F 55F 50F 45F 40F 35F 30F 25F 20F 15F 10F

5F 0F

-5F

-10F

-15F

-20F

0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

65 65 65 65 65 65 65 65 65 65 68 69 70 71 72 73 74 75 76 77 71 73 75 77 79 81 83 85 87 89 74 77 80 83 86 89 92 95 98 101 77 81 85 89 93 97 101 105 109 113 80 85 90 95 100 105 110 115 120 125 83 89 95 101 107 113 119 125 131 137 86 93 100 107 114 121 128 135 142 149 89 97 105 113 121 129 137 145 153 161 92 101 110 119 128 137 146 155 164 173 95 105 115 125 135 145 155 165 175 185

98 109 120 131 142 153 164 175 186 197 101 113 125 137 149 161 173 185 197 209 104 117 130 143 156 169 182 195 208 107 121 135 149 163 177 191 205 219 110 125 140 155 170 185 200 215 113 129 145 161 177 193 209 116 133 150 167 201 218

Table D-4. Header Temperature for a Building Reference Temperature of 70F

0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

70 70 70 70 70 70 70 70 70 70

73 74 75 76 77 78 79 80 81 82

76 78 80 82 84 86 88 90 92 94

79 82 85 88 91 94 97 100 103 106

82 86 90 94 98 102 106 110 114 118

85 90 95 100 105 110 115 120 125 130

88 94 100 106 112 118 124 130 136 142

91 98 105 112 119 126 133 140 147 154

94 102 110 118 126 134 142 150 158 166

97 106 115 124 133 142 151 160 169 178 100 110 120 130 140 150 160 170 180 190 103 114 125 136 147 158 169 180 191 202 106 118 130 142 154 166 178 190 202 214 109 122 135 148 161 174 187 200 213 112 126 140 154 168 182 196 210 115 130 145 160 175 190 205 118 134 150 166 182 198 214 121 138 155 172 189 206 124 142 160 178 196 214

RESET RATIO

D-2

Page 83

APPENDIX D

Table D-5. Header Temperature for a Building Reference Temperature of 75F

RESET RATIO

Air

Temp

75F 70F 65F 60F 55F 50F 45F 40F 35F 30F 25F 20F 15F 10F

5F 0F

-5F

-10F

-15F

Air

Temp

80F 80 80 80 80 80 80 80 80 80 80 75F 83 84 85 86 87 88 89 90 91 92 70F 86 88 90 92 94 96 98 100 102 104 65F 89 92 95 98 101 104 107 110 113 116 60F 92 96 100 104 108 112 116 120 124 128 55F 95 100 105 110 115 120 125 130 135 140 50F 98 104 110 116 122 128 134 140 146 152 45F 101 108 115 122 129 136 143 150 157 164 40F 104 112 120 128 136 144 152 160 168 176 35F 107 116 125 134 143 152 161 170 179 188 30F 110 120 130 140 150 160 170 180 190 200 25F 113 124 135 146 157 168 174 190 201 212 20F 116 128 140 152 164 176 188 200 212 15F 119 132 145 158 171 184 197 210 10F 122 136 150 164 178 192 206

5F 125 140 155 170 185 200 215 0F 128 144 160 176 192 208

-5F 131 148 165 182 199 216

-10F 134 152 170 188 206

0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

75 75 75 75 75 75 75 75 75 75

78 79 80 81 82 83 84 85 86 87

81 83 85 87 89 91 93 95 97 99

84 87 90 93 96 99 102 105 108 111

87 91 95 99 103 107 111 115 119 123

90 95 100 105 110 115 120 125 130 135

93 99 105 111 117 123 129 135 141 17

96 103 110 117 124 131 138 145 152 159

99 107 115 123 131 139 147 155 163 171 102 111 120 129 138 147 156 165 174 183 105 115 125 135 145 155 165 175 185 195 108 119 130 141 152 163 174 185 196 207 111 123 135 147 159 171 183 195 207 219 114 127 140 153 166 179 192 205 218 117 131 145 159 173 187 201 215 120 135 150 165 180 195 210 123 139 155 171 187 203 219 126 143 160 177 194 211 129 147 165 183 201 219

Table D-6. Header Temperature for a Building Reference Temperature of 80F

RESET RATIO

0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

D-3

Page 84

APPENDIX D

Table D-7. Header Temperature for a Building Reference Temperature of 90F

RESET RATIO

Air

Temp

90F 85F 80F 75F 70F 65F 60F 55F 50F 45F 40F 35F 30F 25F 20F 15F 10F

5F 0F

0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

90 90 90 90 90 90 90 90 90 90

93 94 95 96 97 98 99 100 101 102

96 98 100 102 104 106 108 110 112 114

99 102 105 108 111 114 117 120 123 126 102 106 110 114 118 122 126 130 134 138 105 110 115 120 125 130 135 140 145 150 108 114 120 126 132 138 144 150 156 162 111 118 125 132 139 146 153 160 167 174 114 122 130 138 146 154 162 170 178 186 117 126 135 144 153 162 171 180 189 198 120 130 140 150 160 170 180 190 200 210 123 134 145 156 167 178 189 200 126 138 150 162 174 186 198 210 129 142 155 168 181 194 207 132 146 160 174 188 202 216 135 150 165 180 195 210 138 154 170 186 202 218 141 158 175 192 209 144 162 180 198 216

D-4

Page 85

APPENDIX E

MENU & OPTION FACTORY DEFAULT

BOILER DEFAULT SETTINGS

Setup Menu

Password 0

Language English

Unit of Temp Fahrenheit

Comm Address 0

Baud Rate 9600

Configuration Menu

Internal Setpt 130°F

Unit Type Boiler

Unit Size 3.0 MBTU

Boiler Mode Constant Setpoint

Remote Signal (If Mode = Remote Setpoint, Direct Drive or Combination)

Bldg Ref Temp (If Boiler Mode = Outdoor Reset)

4 – 20 mA / 1-5V

70°F

Reset Ratio (If Boiler Mode = Outdoor Reset)

Outdoor Sensor Disabled

System Start Tmp (If Outdoor Sensor = Enabled)

Setpt Lo Limit 60°F

Setpt Hi Limit 200°F

Temp Hi Limit

Max Fire Rate 100%

Pump Delay Timer 0 min

Aux Start On Dly 0 sec

Failsafe Mode Shutdown

mA Output Fire Rate Out

CAUTION: DO NOT Change

Lo Fire Timer 2 sec

Setpt Limit Band (If Setpt Limiting = Enabled) 5°F

1.2

60°F

215°F

Tuning Menu

Prop Band 70°F

Integral Gain 1.00

Derivative Time 0.0 min

E-1

Page 86

Page 87

APPENDIX F

REV.

(71.1)

3/4" ELECTRICAL

CONDUIT CONNECTION

LIFTING LUGS

(20.1)

7 15/16

CAPACITY MBH

MIN. RELIEF VA.

(38.0)

PANEL

DISPLAY

CONTROL

AP-A-811

CONDENSATE PORT

INLET CONN.

(201.4)

5 7/8

2" NPT NATURAL GAS

(14.9)

1" NPT GAS

VENT CONN.

INLET CONN.

(92.2)

36 1/4

"B"

"C"

"A"

FOR "IRI" GAS

TRAIN OPTION" ONLY

(58.4)

DOOR SWING

(84.7)

64 (162.6)

6 7/8

(17.4)

(36.4)

14 5/16

3000

8" EXHAUST

OUTLET

7 7/16

(18.9)

8" AIR INLET

78 (198.1)

(45.7)

(96.7)

THIS AREA TO BE

ACCESSIBLE FOR

MAINTENANCE.

(6.6)

2 5/8

4"-150# FLG'D

COLD WATER

PRESS. RELIEF VALVE

NORTHVALE, NJ 07647

GAS FIRED BOILER

DIMENSIONAL DRAWINGS

BENCHMARK 3 MIL. LOW NOx BTU

AERCO

CONDENSATE PORT

UNIT FLUSH AT REAR

4" CONCRETE PAD - SET

INLET CONN.

OPTION ONLY

FOR DUAL-FUEL

2" NPT PROPANE GAS

1-1/2" NPT

DRAIN CONN.

072606

SIZE

DATE

REV.DATE

CHKD. APPD.CZDWN.BY

SCALE

SQ.FT.

HT'G SURFACE

TEST PRESS.

(PSIG)

TEMP. (°F)

MAXIMUM

HEAT EXCHANGERS & COMBUSTION CHAMBER DESIGN STANDARDS

PRESS. (PSIG)

MAX. WORKING

(32.4)

178

13.5

(137.0)

54 5/16

240

4"-150# FLG'D

SECTION VIII STAMP U (SECONDARY H.X.)

160 210

69 5/8

(176.9)

"C"

DIM.

25 5/16

PRESS./TEMP. GAUGE

"B"

DIM.

"A"

DIM.

42 1/8

(107.0)

(64.3)

FOR IRI

N/A

(73.5)

28 15/16

N/A

OPTION

GAS TRAIN

(39.2)

15 7/16

(64.6)

25 7/16

(30.6)

12 1/16

(41.1)

16 3/16

(64.6)

25 7/16

HOT WATER OUTLET CONN. (SEE NOTE 3)

MODEL

ASME B & PV CODE: SECTION IV STAMP H (PRIMARY H.X.)

BMK3.0 LN

ONLY

NAT. GAS

WITH FM

DUAL-FUEL

WITH IRI

GAS TRAIN

DUAL-FUEL

12 3/4

(34.3)

5 1/4

(13.3)

23 5/8 (60.0)

23 3/16 (58.8)

(LOCATED INSIDE THE BOILER) IS LEVEL OR SLOPING UP AS IT EXITS THE BOILER.

3) FIELD PIPING TO THE BOILER MUST ENSURE THAT THE HOT WATER OUTLET CONNECTION FLEXIBLE PIPING

2) RELIEF VALVE, TRIDICATOR & CONDENSATE TRAP ARE INCLUDED SEPARATELY IN SHIPMENT.

1) ALL DIMENSIONS SHOWN ARE IN INCHES (CENTIMETERS).

NOTES:

GAS TRAIN

F-1

Page 88

APPENDIX F

F-2

Page 89

APPENDIX F

F-3

Page 90

APPENDIX F

F-4

Page 91

APPENDIX F

F-5

Page 92

APPENDIX F

F-6

Page 93

EXHAUST MANIFOLD

APPENDIX F

F-7

DESCRIPTIONQTYPART NO.ITEM

1 2 3

EXHAUST MANIFOLD139033

EXHAUST MANIFOLD SEAL349102

CONNECTING MANIFOLD139036

GAS TRAIN ASSEMBLY

ITEM PART NO. QTY DESCRIPTION

STD FM GAS TRAIN ASSEMBLY

IRI GAS TRAIN ASSEMBLY

DUAL FUEL FM GAS TRAIN

DUAL FUEL IRI GAS TRAIN

(3)

22026-1 22026-2 22040-1 22040-2

BURNER & AIR/FUEL VALVE

DESCRIPTION

BURNER ASSEMBLY

(SEE PL-A-151)

A/F VALVE ASSEMBLY

DUEL FUEL A/F VALVE ASSY.

QTYPART NO.ITEM

1240306

24010

24010-1

BMK3.0LN STAGED

1240398 2810309

18101910

IGNITION ASSY.

(PART OF BURNER ASSY.)

BURNER GASKET

(PART OF BURNER ASS'Y)

BURNER HOUSING GASKET

(PART OF BURNER ASS'Y)

HOSES,GASKETS, & INSULATION

ITEM PART NO. QTY DESCRIPTION

27 88003 1 O-RING #2-339 28 59041 1 HOSE ASSEMBLY, 4"

29 80024-8 1 30 80024-12 1

31 80021-12 1

INSULATION 4" FLEX PIPE 8 LONG

INSULATION 4" FLEX PIPE 12" LONG

INSULATION 4" PIPE 12" LONG

32 80022 1 CONNECTING INSULATION 33 80023

TOP MANIFOLD INSULATION

34 4-58 3 4" FLANGE GASKET 35 62005 1 CORD GRIP 36 59030 1 HOSE ASSY, 4" (FLEXIBLE) 37

HEAT EXCHANGER

DESCRIPTIONQTYPART NO.ITEM

80018

1 18001912 18002013

PRIMARY HEAT EXCH.

UPPER INSULATION

PRIMARY HEAT EXCH.

LOWER INSULATION

SECONDARY HEAT EXCH.

INSULATION

PRIMARY HEAT EXCH.12803014

SECONDARY HEAT EXCH.12802915

BLOWER

ITEM PART NO. QTY

16 24045

1 BLOWER ASSEMBLY

DESCRIPTION

17 123815 1 IRIS AIR DAMPER 18 123681 1

8"x6" REDUCING COUPLING

19 33028 1 BLOWER BRACKET 20 124245 4 5/16 DAMPENER 21 81057 1 BLOWER GASKET 22 96006 1 6" 90 DEG ELBOW 23 96009 1 24

6" DIAM. x 4" LG DUCT W/POR

6" DIAM. x 4" LG DUCT196008

REDUCER OFFSET COVER112399025

CLAMP HOSE SAE #96112358326

AERCO

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

BENCHMARK 3.0 LOW NOx

BOILER PARTS LIST

DRAWN BY ESD

DATE 12/02/08

PL - A - 150

(SHEET 1 OF 7)

Page 94

CONTROLS

APPENDIX F

F-8

ITEM PART NO. QTY DESCRIPTION

38 123966 1 OVER TEMP SWITCH AUTO 39 123552 1 OVER TEMP SWITCH MANUAL 40 61002-7 1 41 61002-5 1

BLOWER PROOF SWITCH

BLOCKED INLET SWITCH

42 161560 1 I /O WIRING BOX 43 181197 1 C-MORE CONTROL BOX

GP-122464

1 IGNITION TRANSFORMER

45 33030 1 VFD MOUNTING BRACKET

64012-1

64012-2 VFD (460V)

VFD (208-230 V)

(4)

48 124310 1 460V TRANSFORMER

(4)

49 124380 1 500 VAC, 4 AMP FUSE 50 58009 1 460V Terminal Cover Kit

(4)

52 79002 1 460V TRANSFORMER LABEL 53 61011 1 AIR TEMP SENSOR 54 64018 1 TEMPERATURE TRANSMITTER

GP-122569

1 IGNITION CABLE ASSY. 56 63016 1 BMK3.0LN SHELL HARNESS 57 124320 1 BLOWER HARNESS

PROGRAMMED LOGICSTICK

(NON DUAL FUEL)

DUAL FUEL, NAT. GAS - STICK24065-2 DUAL FUEL, PROPANE - STICK

208V POWER WIRING BOX

460V POWER WIRING BOX64017

16301560

BMK3.0LN GAS TRAIN WIRING

HARNESS

(1)

(6)

24065

24065-3

64016

SHELL TEMP. SENSOR112344962

THERMOWELL, DUAL AQUASTAT BULB

116152163

(6)

(7)

(8)

61002-3 61002-15 61002-16

161002-164

LOW GAS PRESSURE SWITCH

HIGH GAS PRESSURE SWITCH

(NON DUAL FUEL)

DUAL FUEL HGPS - NAT. GAS DUAL FUEL HGPS - PROPANE

OTHER ACCESORIES / PARTS

DESCRIPTIONQTYPART NO.ITEM

(1)(2)

(1)

(7) (1)

SEE SD-A-700

69087 −

112354068

PRESS./TEMP. GAUGE1

PRESSURE RELIEF VALVE1

EXT. MANUAL SHUT-OFF VALVE

1" DRAIN HOSE, 60" LG19103069 1-1/2" NPT BALL VALVE112820-1170

CONDENSATE FLOAT15904371

(1)

COND. TRAP ASSEMBLY12406072

OTHER DUAL FUEL COMPONENTS

DESCRIPTIONQTYPART NO.ITEM

(1)

(5)

(1)

(5)

(5)(6)

(5) (5) (5)

(5)

16303275

3303677

1 17203078

"PROPANE" LABEL17203173 "NAT. GAS" LABEL17203274

DOUBLE GAS TRAIN WIRING

HARNESS

FUEL SELECTOR SWITCH16502476

FUEL SELECTOR SWITCH

MOUNTINGBRACKET

FUEL SELECTOR SWITCH LABEL

DUAL FUEL WIRING HARNESS16303479

SHEET METAL / PANEL ASSEMBLY

ITEM PART NO QTY DESCRIPTION

80 37004 1 LEFT REAR PANEL 81 37003 1 RIGHT REAR PANEL 82 49028 2 TOP RAIL 83 201233 1 MOUNTING PANEL

84 201113 1

FRONT PANEL

ENCLOSURE

85 201120 1 FRONT DOOR ASSY.

GP-122620

86 87 30022

4 HANDLE 2

TOP PANEL

SIDE PANEL43700288

BMK3.0LN LOGO17400489

OTHER PARTS

ITEM PART NO QTY DESCRIPTION

CUT-OFFLOW WATER 112284361

90 99017 1

NOTES:

NOT SHOWN IN DRAWING

(1) (2)

-5 (30 AND 50 PSI RELIEF VALVE SETTING)

-6 (60,75,100 & 125 PSI RELIEF VALVE SETTING)

-7 (150 PSI RELIEF VALVE SETTING)

(3)

FOR PICTORAL PURPOSES ONLY, FM GAS TRAIN (NON DUAL FUEL) IS SHOWN

(4)

FOR 460 V OPTION ONLY (5) ONLY NEEDED ON DUAL FUEL (6)

PART OF GAS TRAIN ASSY.

TWO (2) REQUIRED FOR DUAL FUEL BMK3.0 LN(7)

(8)

SEE DRAWING AP-A-826 FOR DUAL FUEL DETAILS

GAS PRESSURE SNUBBER -

PART OF GAS TRAIN

AERCO

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

BENCHMARK 3.0 LOW NOx

BOILER PARTS LIST

DRAWN BY

DATE 12/02/08

PL - A - 150

(SHEET 2 OF 7)

Page 95

APPENDIX F

F-9

18 24

23 40

DETAIL A

SCALE 1 : 10

AERCO

BENCHMARK 3.0 LOW NOx

DRAWN BY ESD

DATE 12/02/08

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

BOILER PARTS LIST

PL - A - 150

(SHEET 3 OF 7)

Page 96

APPENDIX F

F-10

SECTION B-B

SCALE 1 : 18

35 63

AERCO

BENCHMARK 3.0 LOW NOx

BOILER PARTS LIST

DATE

12/02/08

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

SDDRAWN BY

PL - A - 150

(SHEET 4 OF 7)

Page 97

APPENDIX F

F-11

DETAIL B:

SEE DETAIL C

DETAIL C:

FUEL SELECTOR SWITCH

(DUAL FUEL ONLY)

7776

65 90

FM GAS TRAIN

(NON DUAL FUEL)

AERCO

BENCHMARK 3.0 LOW NOx

DRWN BY

DATE 12/02/08

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

BOILER PARTS LIST

PL - A - 150

(SHEET 5 OF 7

)

Page 98

APPENDIX F

F-12

AERCO

BENCHMARK 3.0 LOW NOx

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

BOILER PARTS LIST

DRWN BY SD

DATE 12/02/08

PL - A - 150

(SHEET 6 OF 7

)

Page 99

APPENDIX F

F-13

AERCO

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

BENCHMARK 3.0 LOW NOx

BOILER PARTS LIST

DRWN BY SD

DATE 12/02/08

PL - A - 150

(SHEET 7 OF 7

)

Page 100

AERCO BMK 3.0 LN Nat. Gas Jan 2009 User Manual Gas Jan 2009

Specifications and Main Features

Frequently Asked Questions

User Manual

Foreword

Chapter 8- TROUBLESHOOTING GUIDE

APPENDIX A - BOILER MENU ITEM DESCRIPTIONS

APPENDIX B - STARTUP, STATUS AND FAULT MESSAGES