AERCO BMK 2.0 LN Nat. Gas User Manual

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Page 1

Instruction

GF-110LN

No.

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

Installation, Operation

& Maintenance Instructions

Benchmark™ Series Gas Fired Low NOx Boiler System

Condensing, Modulating

Forced Draft, Hot Water Boiler

2,000,000 BTU/H Input

Applicable To Serial Numbers G-05-1393 and above

Patent # : 2.155.12

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) (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-110LN - AERCO BENCHMARK 2.0 GAS FIRED LOW NOx BOILER

Operating & Maintenance Instructions

FOREWARD A

Chapter 1 – SAFETY PRECAUTIONS 1-1

Para. Subject Page

1-1 Safety Warnings 1-1 1-2 Emergency Shutdown 1-1

Chapter 2 – INSTALLATION PROCEDURES 2-1

Para. Subject Page

2.1 Receiving the Unit 2-1

2.2 Unpacking 2-1

2.3 Installation 2-2

2.4 Gas Supply Piping 2-3

2.5 Electrical Supply 2-4

2.6 Mode of Operation and Field Control Wiring

2-5

Para. Subject Page

1-3 Prolonged Shutdown 1-1

Para. Subject Page

2.7 I/O Box Connections 2-7

2.8 Auxiliary Relay Contacts 2-8

2.9 Flue Gas Vent Installation 2-9

2.10 Combustion Air 2-9

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 3-3

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

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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 6-1

6.4 Low Water Level Fault Test 6-2

6.5 Water Temperature Fault Test 6-2

6.6 Interlock Tests 6-2

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

Chapter 7 – MAINTENANCE REQUIREMENTS 7-1

Para. Subject Page

7.1 Maintenance Schedule 7-1

7.2 Spark Igniter 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

7-4

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

B-1

C-1

D-1

WARRANTIES W-1

App Subject Page

E Boiler Default Settings E-1 F Dimensional and Part Drawings F-1 G Piping Drawings G-1 H Wiring Schematics H-1 I Recommended Periodic Testing

Checklist

J Benchmark Control Panel Views J-1

I-1

iii

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FOREWORD

Foreword

The AERCO Benchmark 2.0 LN Boiler is 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’s 20:1 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.

When installed and operated in accordance with this Instruction Manual, the Benchmark 2.0 LN Boiler complies with the NOx emission standards outlined in:

• South Coast Air Quality Management District (SCAQMD), Rule 1146.2

• Texas Commission on Environmental Quality (TCEQ), Title 30, Chaptr 117, Rule117.465

Whether used in singular or modular arrangements the Benchmark 2.0 LN 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 general warnings and cautions must be given the same attention as specific precautions included in these instructions. In addition to all the requirements included in this 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 ANY BOILER 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 the loss of operating effectiveness.

CAUTION!

Many soaps used for gas pipe leak testing are corrosive to metals. The piping must

be rinsed thoroughly with clean water after leak checks have been completed.

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.

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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 must 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 RECEIVING THE UNIT

Each Benchmark is shipped as a single crated unit. The shipping weight is approximately 1850 pounds, and must be moved with the proper rigging equipment for safety and to avoid damages. The unit should be completely inspected for shipping damage and 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. 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.

2.2 UNPACKING

Carefully unpack the unit taking care not to damage the unit jacket when cutting away packaging materials. A close inspection of the unit should be made to determine if there has been any damage not indicated by the Tip-NTell. The freight carrier should be notified immediately if any damage is detected. The following accessories come standard with each unit and are packed separately within the unit’s’ packing container or are factory installed on the boiler.

• Pressure/Temperature Gauge

• Spare Spark Ignitor

• Spare Flame Detector

• ASME Pressure Relief Valve

• Regulator Adjustment Tool (One per

Site)

• Condensate Drain Trap

• 2” Gas Supply Shutoff Ball Valve

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

Figure 2.1

Boiler Clearances

2-1

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INSTALLATION

2.3 INSTALLATION

The unit must be installed by qualified personnel (i.e. licensed plumber, gas fitter, etc.) in compliance with local and state regulations. The prescribed clearances for service are shown in Figure 2.1. The minimum required by AERCO, are listed below. Local building codes may require more clearance and take precedence

Minimum clearances required: Sides 24" Front 24" Rear 36" Top 18"

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

clearance dimensions,

WARNING!

KEEP UNIT AREA CLEAR AND FREE FROM COMBUSTIBLE MATERIALS AND

FLAMMABLE VAPORS AND LIQUIDS.

CAUTION!

While packaged on the shipping skid, the boiler must be moved by pallet jack or forklift from the rear only.

2.3.1. SETTING THE UNIT

The unit must be installed on a 4 to 6 inch housekeeping pad for proper condensate drainage. If anchoring the unit, see the dimensional drawings in Appendix F for anchor location. Lifting lugs are provided for moving the unit when it has been removed from the shipping skid (See Fig. 2.2). USE ONLY THE LIFTING LUGS TO MOVE THE UNIT. Remove the rear top panel from the unit to provide access to the lifting lugs. Remove the four (4) lag screws securing the boiler to the shipping skid. Lift the unit off the shipping skid and position it on to the 4 to 6 inch housekeeping concrete pad (required) in the desired location.

In multiple unit installations, it is important to plan the position of each unit. Sufficient space for piping connections and future maintenance requirements must be given. All piping must include ample provision for expansion.

If installing a Combination Control (CCP) system, it is important to identify and place the

Combination Mode units in the proper physical location. If these boilers are not properly located, it will be necessary to reprogram them.

Figure 2.2

Lifting Lug Location

2.3.2 SUPPLY AND RETURN PIPING

The Benchmark 2.0 utilizes 4" 150# flanges for the water system supply and return piping connections. See Appendix F for dimensional data. The physical location of the supply and return piping connections is on the rear of the unit (See Fig 2.3 For Details).

BOILER SUPPLY (4"-150# FLG'D CONN.)

BOILER RETURN (4"-150# FLG'D CONN.)

Figure 2.3

Supply and Return Location

2-2

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2.3.3 CONDENSATE DRAIN & PIPING

The Benchmark Boiler is designed to condense water vapor from the flue products. Therefore, the installation must have provisions for suitable drainage or collection. A 1/2” NPT drain connection is provided on the exhaust manifold (see Fig 2.4). A separate condensate drain trap (part no. 24060) is shipped loose and must be installed on the floor behind the unit. Connect the trap to the exhaust manifold as follows:

1. First, install a 1/2” NPT nipple in the condensate drain port (Fig. 2.4). Next, connect a 3/4-to 1/2” reducer to the 1/2” nipple.

2. On the condensate drain trap, install 3/4” NPT nipples in the tapped inlet and outlet of the trap.

3. Attach a length of 1” I.D. polypropylene hose between the exhaust manifold drain and the inlet side of the condensate trap (Fig 2.5). Secure both ends of the hose with clamps. Drainage from the condensate drain trap outlet must be by gravity to a nearby floor drain via a polypropylene hose or suitable piping.

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 11 GPH. The condensate drain trap, associated fittings and drain line must be removable for routine maintenance. Do Not

Figure 2.4

Condensate Drain Connection Location

hard pipe.

INSTALLATION

Figure 2.5

Condensate Trap Installation

2.4. GAS SUPPLY PIPING

The AERCO Gas Fired Equipment Gas Components and Supply Design Guide (GF-2030LN) must be consulted before any gas piping is designed or started.

WARNING!

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

CAUTION!

Many soaps used for gas pipe leak testing are corrosive to metals. Therefore, AERCO recommends the use of non-corrosive soaps for leak tests. The piping must be rinsed thoroughly with clean water after leak checks have been completed.

NOTE:

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

The location of the 2" inlet gas connection is on the rear of the unit as shown in Figure 2.5.

All pipes should be de-burred and internally cleared of any scale or iron chips before installation. No flexible connectors or nonapproved gas fittings should be installed. Piping

2-3

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INSTALLATION

should be supported from floor, ceiling or walls only and must not be secured to the unit.

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

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

2.4.1 GAS SUPPLY SPECIFICATONS

− Natural Gas : The maximum static pressure to the unit must be no more than 2 psi. Minimum natural gas operating pressure is 5.3“ W.C. for FM gas trains & 5.5“ W.C. for IRI gas trains when the unit is firing at maximum input (2000 cfh). For Benchmark 2.0 Low NOx boilers configured for De-Rated capacity, the required minimum natural gas operating pressure is 4.0” W.C. for FM gas trains (4.2” W.C. for IRI gas trains) at maximum input of 1,750,000 BTU/hr (1750 cfh).

2.4.3 IRI GAS TRAIN KIT

The IRI gas train is an optional gas train required in some areas by code or for insurance purposes. The IRI gas train is factory pre-piped and wired.

2.5 ELECTRICAL SUPPLY

The AERCO Gas Fired Equipment Electrical Power Wiring Guide, (GF-2060), must be consulted in addition to the following material before wiring to the unit is started. External AC power connections are made to the unit inside the power box on the front panel of the unit, behind the removable front door (Figure 2.6).

NOTE:

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

2.4.2 MANUAL GAS SHUTOFF VALVE

A 2” manual gas shut-off valve is furnished with each unit. The valve should be positioned on the inlet to the unit, as shown in Figure 2.5.

Figure 2.5

Manual Shut-Off Valve Location

Figure 2.6

AC Input Terminal Location

2.5.1 ELECTRICAL REQUIREMENTS

The Benchmark Boiler is available in one three different AC power configurations:

220 Vac/1 Phase/60 Hz @ 20 amps 208 Vac/3-Phase/60 @15 amps 460 Vac/3-Phase/60 Hz @ 15 amps

2-4

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INSTALLATION

Each of the above power configurations contain a Power Box with a terminal block which matches the configuration ordered. The three different terminal block configurations are shown in Figure 2.7. A wiring diagram showing the required AC power connections is provided on the front panel of each Power Box.

Each Benchmark Boiler must be connec ted 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 acc ordance with the National Electrical Code and/or with any applicable local codes.

For electrical power wiring diagrams, see the Benchmark Electrical, Power Wiring Guide, GF2060

2.6 MODE OF OPERATION and FIELD CONTROL WIRING

The Benchmark Boiler is available in several different modes of operation. While each unit is factory configured and wired for a particular mode, some field wiring may be required to complete the installation. This wiring is typically run to the Input/Output (I/O) Box located on the front of the unit behind the removable front door (see Fig. 2.8). A brief description of each mode of operation, and their requirements, is described in the following paragraphs. Additional information concerning field wiring is provided in paragraphs 2.7.1 through 2.7.9. For additional information on modes of operation, refer to Chapter 5.

Figure 2.7

AC Terminal Block Configurations

Figure 2.8

I/O Box Terminal Location

2.6.1 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 electrical supply connections are required for this mode. However, if desired, fault monitoring or enable/disable interlock wiring can be utilized (see paragraphs 2.7.9.1 and 2.7.10).

2-5

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INSTALLATION

2.6.2 INDOOR/OUTDOOR RESET MODE

This mode of operation increases supply water temperature as outdoor temperatures decrease. An outside air temperature sensor (AERCO PN

122790) is required. The sensor MUST BE wired

to the I/O Box wiring terminals (see Fig. 2.9). For more information concerning the outside air sensor installation, refer to paragraph 2.7.1

Figure 2.9 I/O Box Terminal Strip

2.6.3 BOILER MANAGEMENT SYSTEM

(BMS) 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 2-9). 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 Modbus 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 GF-108M (BMS Model 168) and GF-124 (BMS II Model 5R5-

384), BMS -Operations Guides.

2.6.4 REMOTE SETPOINT and DIRECT DRIVE MODES

The Benchmark Boiler can accept several types of signal formats from an Energy Management System 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

paragraph 2.7.4) Network – (RS485 Modbus. See para. 2.7.7)

2-6

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INSTALLATION

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 2.7.3.

2.6.4 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 connected 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 done using a shielded twisted pair of 18- 22 AWG wire and 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.

2.7 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 2.9 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.

2.7.1 OUTDOOR SENSOR IN

An outdoor air temperature sensor (AERCO Part No. 122790) will be required mainly 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. The factory default for the outdoor sensor is DISABLED. To enable the sensor and/or choose 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 Figs. 2.8 and 2.9). Wire the sensor using a twisted shielded pair cable of 1822 AWG wire. There is no polarity when terminating the wires. The shield is to be connected only to the terminals labeled SHEILD 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.

2.7.2 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 and must be similar to AERCO BALCO wire sensor P/N 12449. A resistance chart for this sensor can be found in APPENDIX C.

2.7.3 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 supplied signals must be floating (ungrounded) signals. Connections between the source and the Boiler’s I/O Box must be made using twisted shielded pair of 18 –22 AWG wire such as Belden 9841(see Fig. 2.9). Polarity must be maintained and the shield must be connected only at the source end and must be left floating (not connected) at the Boiler’s I/O Box.

2-7

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INSTALLATION

Whether using voltage or current for the drive signal, they are linearly mapped to a 40

F setpoint or a 0% to 100% firing rate. No

240 scaling for these signals is provided

2.7.4 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.

2.7.5 SHIELD

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

2.7.6 mA OUT

These terminals provide a 4 to 20 mA output that can be used to monitor setpoint ( 40

F), outlet temperature (30o to 240oF), or fire

240 rate (0% to 100%). This function is enabled in the Configuration Menu (Chapter 3, Table 3.4).

2.7.7 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 or other suitable device.

2.7.8 EXHAUST SWITCH IN

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

2.7.9 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 (Fig. 2.9). The wiring terminals for thes e interlocks are 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 labeled REMOTE INTL’K IN and

2-8

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.

2.7.9.1 REMOTE INTERLOCK IN

The remote interlock circuit (REMOTE INTL’K IN) is provided to remotely start (enable) and stop (disable) the Boiler if desired. The circuit is 24 VAC and comes factory pre-wired closed (jumped).

2.7.9.2 DELAYED INTERLOCK IN

The delayed interlock circuit (DELAYED INTL’K IN) is typically used in conjunction with the auxiliary relay described in paragraph 2.8. 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).

2.7.10 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 2.9

2.8 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

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INSTALLATION

firing). Its contacts are rated for 120 VAC @ 5 amps. Refer to Figure 2.9 to locate the AUX RELAY terminals for wiring connections.

2.9 FLUE GAS VENT INSTALLATION

The AERCO Venting and Combustion Air Guide, GF-2050, 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-2050, must be used for safety and code compliance. Because the unit is capable of discharging low temperature exhaust gases, the flue must be pitched back to the unit a minimum of 1/4" per foot to avoid any condensate pooling and to 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”/+0.25" 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.

2.10 COMBUSTION AIR

The AERCO Venting and Combustion Air Guide, GF-2050, MUST be consulted before any flue or combustion supply air venting is designed or started. 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.

The combustion air must be free of chlorine, halogenated hydrocarbons, or other chemicals that can become hazardous when us ed 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 Benchmark is UL listed for 100% sealed combustion and can be ordered with a sealed combustion option, or can be installed using room air as long as there is an adequate supply.

(See paragraph 2.10.3 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 blower suction and the knockout at the top of the unit will be and should remain in place.

The more common methods of supplying combustion air are outlined below. For more information concerning combustion air, consult the AERCO GF-2050, Venting and Combustion Air Guide.

2.10.1 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 boiler input. The free area must take into account restrictions such as louvers and bird screens.

2.10.2 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 BTUH of total boiler input. The free area must take into account any restrictions such as louvers.

2.10.3 SEALED COMBUSTION

The BENCHMARK boiler is UL listed for 100%sealed combustion and can be ordered with a sealed combustion option or without. Units ordered in the sealed combustion configuration will come with an air inlet assembly installed on the blower. The knockout at the top of the boiler must be removed and the combustion air ductwork must be attached to the 6" x 8" adapter that is provided just below the knockout. Remove and discard the screen attached to the adapter.

In a sealed combustion air application, the combustion air ducting pressure los ses must be taken into account when calculating the total maximum allowable venting run. See the AERCO Venting and Combustion Air Guide, GF-

2050. When using the boiler in a sealed combustion air configuration, each unit must have a minimum 8" diameter connection at the unit.

2-9

Page 20

Page 21

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 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 initial installation procedures must be satisfied before attempting to start the unit.

WARNING:

THE ELECTRICAL VOLTAGES IN THIS SYSTEM MAY INCLUDE 460, 220, 120 AND 24 VOLTS AC. IT MUST NOT BE SERVICED OR ACCESSED BY OTHER THAN 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 PERSONNEL INJURY OR PROPERTY DAMAGE. THIS SITUATION WILL VOID ANY WARRANTY.

3.2. CONTROL PANEL DESCRIPTION

The Benchmark Control Panel shown in Figure 3-1 contains all of the controls, indicators and displays necessary to operate, adjust and troubleshoot the Benchmark 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

4 RS-232 Port Port permits a Laptop Computer or External Modem to be

5 FAULT Indicator Red FAULT LED indicator lights when a boiler alarm

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

7 READY Indicator 8 ON/OFF Switch

LOW WATER LEVEL TEST/RESET Switches

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 Menu Selection

connected to the boiler 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 when 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 CLEAR resets the display.

FUNCTION

3-2

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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

11 AUTO/MAN Switch This switch toggles the boiler between the Automatic and

12 FIRE RATE Bargraph 20 segment red LED bargraph continuously shows the Fire

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

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.

Rate in 5% increments from 0 to 100%

3-3

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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 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.

display the options in the Bottom-Up sequence. The menu options will wraparound 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

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. Factory Default settings for all menu options are listed in Appendix E. Refer to Appendix B for listings and descriptions of displayed

startup, status and error messages.

3-4

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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 other displayed items. Since this menu is “ReadOnly”, it can be viewed at any time without entering a password. Press the ▲ arrow key to display the menu items in the order listed (TopDown). 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 time-out after 1 hour. Therefore, the correct password must be reentered when required. In addition to permitting password entries, the

Table 3-2. Operating Menu

Available Choices or Limits

Menu Item Display Minimum Maximum Default

Status Message 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

Comm Address 0 127 0 Baud Rate 2400, 4800

9600, 19.2K

Software Ver 0.00 Ver 9.99

Setup Menu is also used to enter date and time, language to be used for display messages, 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).

Fahrenheit

Celsius

9600

3-5

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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

Water Heater

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 Remote Signal (If Mode = Remote Setpoint, Direct Drive or Combination) Bldg Ref Temp (If Boiler Mode = Outdoor Reset) Reset Ratio (If Boiler 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 240°F 200°F Temp Hi Limit 40°F 240°F 215°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 Failsafe Mode Shutdown or Constant Setpt Shutdown mA Output Setpoint, Outlet Temp,

Lo Fire Timer 2 sec 120 sec 2 sec Setpt Limiting Enabled or Disabled Disabled Setpt Limit Band 0°F 10°F 5°F

4 – 20 mA/1 – 5V

0 -20 mA/0 – 5V

BMS (PWM Input

40°F 240°F 70°F

0.1 9.9 1.2

30°F 100°F 60°F

Fire Rate Out, Off

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

Boiler

1.0 MBTU

Constant Setpoint

Direct Drive

4 – 20 mA, 1-5V

Network

Off

3-6

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CONTROL PANEL OPERATING PROCEDURES

3.7. TUNING MENU

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

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 2.0 min 0.0 min Reset Defaults? Yes

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

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:

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

Are You Sure?

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 switch in the Safety Shut-Off Valve (SSOV) is closed (Figure 3-3).

Figure 3-3.

Safety Shut-Off Valve

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

3-7

Page 28

CONTROL PANEL OPERATING PROCEDURES

(a) Blower relay energizes and turns on

blower.

(b) Air/Fuel Valve rotates to 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%.

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 lowfire position.

Figure 3-5.

Blower Proof Switch

Figure 3-4.

Air/Fuel Valve In Purge Position

4. Next, the blower proof switch (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.

(b) Simultaneously, the ignition transformer

and the staged ignition solenoid valve will be activated. The ignition transformer provides ignition spark. The activated (open) solenoid valve allows a small volume of gas to flow directly to the burner assembly (Appendix F).

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.

3-8

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CONTROL PANEL OPERATING PROCEDURES

8. With the unit firing properly, it will be controlled by the temperature controller

circuitry. The FIRE RATE will be continu-

ously displayed on the front panel bargraph.

BLOWER

DIAL (DETAIL "A")

BURNER

Once the demand for heat has been satisfied, the Control Box will turn off the gas valve. The blower relay will be deactivated and the Air/Fuel

Valve will be closed. Standby will be displayed.

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: 16%

Normally, these settings should not require adjustment

DETAIL "A"

Figure 3-6.

Air/Fuel Valve In Ignition Position

3-9

Page 30

Page 31

INITIAL START-UP

Chapter 4 - INITIAL START- UP

4.1 INITIAL START- UP REQUIREMENTS

The initial start-up of the Benchmark Boiler is comprised of the following steps:

• installation completed

• combustion calibration

• proper setting of controls and limits

• mode of operation settings (see Chapter 5)

• safety device testing (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 for the unit to operate safely, at a high thermal efficiency, and 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 control test procedures in chapter 6 to complete the initial unit start-up.

An AERCO Gas Fired Startup Sheet, included with each BENCHMARK, 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

WARNING!

DO NOT ATTEMPT TO FIRE THE BOILER WITHOUT FULL WATER LEVEL. THIS CAN SERIOUSLY DAMAGE THE UNIT AND MAY RESULT IN PERSONAL INJURY OR PROPERTY DAMAGE. THIS IS NOT COVERED BY WARRANTY.

CAUTION!

All 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 AND INSTRUMENTATION

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

1. A digital combustion analyzer with oxygen accuracy to ± 0.2%, and carbon monoxide in PPM.

2. A 16" W .C. manometer or equivalent gauge and plastic tubing.

3. Adjustable wrench to remove 1/8” plug from pressure sensing port on SSOV.

4. Two, 1/8" NPT to barbed fittings for use with the gas supply regulator.

5. AERCO differential gas pressure regulator adjustment tool P/N 123643

6. Small and large flat blade screwdrivers.

7. Tube of silicone adhesive

4.2.2 INSTALLING THE SUPPLY GAS

MANOMETER

1. Check to ensure that the 1/8” NPT ball valve downstream of the SSOV is closed.

2. Remove the 1/8" NPT pipe plug from the ball valve downstream valve (SSOV) (see Figure 4.1).

3. Install a barbed fitting into the pipe plug tapping.

4. Attach one end of a length of plastic tubing to the barbed fitting and one end to the 16" W.C. manometer.

5. Open the 1/8” NPT ball valve downstream of the SSOV.

of the safety shut off

4-1

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INITIAL START-UP

Figure 4.1

1/8” Gas Plug Location

4.2.3 PREPARING THE FLUE VENT PROBE HOLE

1. Locate and remove the plug on the left or right side of the exhaust manifold (see Figure 4.2).

2. Adjust the stop on the combustion analyzer probe, if so equipped, so that it extends approximately midway into the flue gas flow. Do not insert the probe at this time.

4.2.4 INSTALLING THE DIFFERENTIAL REGULATOR ADJUSTMENT TOOL FOR NATURAL GAS UNIT.

1. Remove the cap from the differential pressure regulator (see Figure 4.3).

2. Place the gasket from the regulator cap onto the regulator adjustment tool.

3. Prior to installing the tool on the regulator, pull up the screwdriver blade of the tool. Then thread the tool into the regulator and hand tighten.

4. Engage the tool’s screwdriver blade into the regulator’s adjustment screw slot.

REGULATOR CAP

CAP GASKET

REGULATOR ADJUSTMENT TOOL (P.N. 123643)

4-2

Figure 4.2

A Location nalyzer Probe Hole

DIFFERENTIAL

PRESSURE

REGULATOR

Figure 4.3

Differential Regulator Adjustment Tool

Installation For Natural Gas Unit

4.3 NATURAL GAS COMBUSTION

CALIBRATION

The Benchmark ships combustion calibrated from the factory. Recalibration as part of a startup is necessary due to altitude, gas BTU content, gas supply piping and supply gas pressure. Factory test data sheets are shipped with each unit as a reference.

Page 33

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

3. Set the ON/OFF switch in the OFF position. Turn on AC power to the unit. The display will show LOSS OF POWER and the time and date.

4. 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.

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

6. Ensure that the 1/4” ball valve downstream of the SSOV is open.

7. Set the ON/OFF switch to the ON position. Change the fire rate to 40% using the ▲ arrow key. The unit should begin its start sequence and fire.

8. Next, gradually increase the firing rate to 100% in 20% increments and verify that the gas pressure downstream of the SSOV is

4.8” W.C. for both FM and IRI gas trains at 100% firing rate. If not, remove the brass hex nut on the SSOV using the black plastic wrench from the Iris Damper. Make the gas regulator adjustment using a flat-tip screwdriver to obtain 4.8” W.C (see Figure

4.4). For Benchmark 2.0 Low NOx boilers configured for De-Rated capacity (see para.

2.4.1), the gas pressure downstream of the SSOV must be 3.7” W.C. for both FM and IRI gas trains at a 100% firing rate.

CAUTION:

Turn the gas regulator adjustment screw very slowly. Unlike ordinary regulators, this adjustment is very sensitive.

INITIAL START-UP

REGULATOR ADJUSTMENT SCREW

Figure 4.4

Regulator Adjustment Screw Location

9. Lower the firing rate to 40% using the ▼ arrow key. Insert the combustion analyzer probe into the exhaust manifold and allow enough time for the combustion analyzer to settle. Compare the measured oxygen level to the oxygen range for inlet air temperature in Table 1.

10. If needed, adjust the differential regulator until the oxygen reading is within the specified range in Table 1.

NOTE:

Adjust only the differential regulator at 40% control signal. Do not adjust the iris air damper.

Table 1 - Combustion Oxygen Levels for a

40% Firing Rate

Temp (°F)

130 4.6 <30ppm <20ppm 120 4.8 <30ppm <20ppm 110 5.0 <30ppm <20ppm 100 5.2 <25ppm <20ppm

90 5.3 <25ppm <20ppm 80 5.5 <25ppm <20ppm 70 5.6 <25ppm <20ppm 60 5.9 <25ppm <20ppm 50 6.2 <25ppm <20ppm 40 6.4 <25ppm <20ppm 30 6.5 <25ppm <20ppm 20 6.5 <25ppm <20ppm 10 6.5 <25ppm <20ppm

0 6.6 <25ppm <20ppm

-10 6.6 <25ppm <20ppm

-20 6.7 <25ppm <20ppm

-30 6.8 <25ppm <20ppm

-40 6.8 <25ppm <20ppm

40% Fire Rate

NOx (corrected to

3% O

)

4-3

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INITIAL START-UP

11. If the required oxygen level from Table 1 is achieved, proceed to step 18. If the oxygen level is lower than the required value and cannot be sufficiently raised using the differential regulator, proceed to step 12.

12. Close the 1/4” ball valve in the staged ignition assembly downstream of the SSOV.

13. If the oxygen level rises, it is an indication that the staged ignition solenoid is stuck, or is adding gas and preventing the proper oxygen level from being achieved. The solenoid will require replacement. Proceed to step 14.

14. Set the green ON/OFF switch to the OFF position. Turn off AC power to the unit.

15. Replace the staged ignition solenoid. See Figure 8.2 for location of the solenoid.

16. Re-open the 1/4” ball valve downstream of the SSOV.

17. Repeat combustion calibration starting from step 1 of paragraph 4.3.

18. Once the oxygen level is within the specified range at 40%, lower the firing rate to 16%.

19. Oxygen levels at the 16% firing rate should be as shown in Table 2. No adjustment should be necessary. Contact the Factory if the oxygen or carbon monoxide levels are not within the specified range.

NOTE:

If the port being used to sample combustion products at 16% is too far from the unit, the readings may be shifted.

Table 2 - Combustion Oxygen Levels for a

16% Firing Rate

16% Fire Rate

Temp (ºF)

130 120 <20ppm <20ppm 110 <20ppm <20ppm 100

90 80 <20ppm <20ppm 70 <20ppm <20ppm 60 50 40 <20ppm <20ppm 30 <20ppm <20ppm 20 10

0 <20ppm <20ppm

-10 <20ppm <20ppm

-20

-30

-40 <20ppm <20ppm

O2 CO

4.5-8.0

5.5-8.5

6.0-9.0

<20ppm <20ppm

<20ppm <20ppm <20ppm <20ppm

NOx (corrected

to 3% O

)

20. Raise the firing rate to 100%. Gas pressure should still be 4.8” W.C. If it is not, readjust as necessary. For Benchmark 2.0 Low NOx boilers configured for De-Rated capacity (see para. 2.4.1), gas pressure should still be 3.7” W.C. If not, readjust as necessary.

21. Allow the combustion analyzer to settle. Compare the measured oxygen level with the levels in Table 3.

22. If the measured oxygen reading is within the specified level in Table 3, no further adjustment is necessary.

23. If the measured oxygen level is not within specified range in Table 3, adjust the iris damper as necessary until the measured oxygen reading is within specification. (See Figure 4.5).

4-4

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INITIAL START-UP

Table 3 - Combustion Oxygen Levels for

100% Firing Rate

100% Fire Rate

NOx (corrected to

Temp (ºF)

130 4.3 <100ppm <40ppm 120 4.5 <100ppm <40ppm 110 4.7 <100ppm <35ppm 100

90 80 70 5.1 <100ppm <30ppm 60 5.2 <100ppm <30ppm 50 5.3 <100ppm <30ppm 40 30 20 10 5.4 <100ppm <30ppm

0 5.4 <100ppm <30ppm

-10 5.4 <100ppm <30ppm

-20

-30

-40

O2 CO

4.8 <100ppm <30ppm

5.0 <100ppm <30ppm

5.1 <100ppm <30ppm

5.4 <100ppm <30ppm

3% O

1. Put the green ON/OFF switch in the off position. Disconnect the AC power supply to the unit.

)

2. Shut off the gas supply to the unit.

3. Reinstall the brass hex nut back on the regulator.

4. Remove all of the manometers and barbed fittings and reinstall the pipe plugs using a suitable thread compound.

5. Remove the combustion analyzer probe from the tapped hole in the exhaust manifold. Replace the NPT plug previously removed in para. 4.2.3, step 1.

6. Replace the unit’s panels.

4.5 OVER-TEMPERATURE LIMIT

SWITCH

The over-temperature limit switches are located on the plate to the left of the boiler shell. One is a fixed manual reset switch that will shutdown and lock out the boiler if the water temperature reaches 210°F. The other is an adjustable auto reset which allows the boiler to restart, once the temperature drops below its temperature setting. Figure 4.6 shows the location of the over temperature limit switch.

Figure 4.5

Iris Air Damper Location

24. Change the firing rate to 40%. Allow time for the combustion analyzer to settle. Check the measured oxygen reading to insure that it is still within the range as per Table 1.

25. Continue this procedure until oxygen levels at 40%, 16% and 100% firing rates are within the ranges specified in Tables 1, 2 and 3.

4.4 UNIT REASSEMBLY

Once combustion calibration is set properly, the unit can be re-assembled for permanent operation. Proceed as follows:

Figure 4.6

Over Temperature Limit Switch Location

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MODE OF OPERATION

CHAPTER 5 MODE OF OPERATION

5.1 INTRODUCTION

The Benchmark 2.0 Low NOx 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 unit 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. The 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 Boilr. 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 2.7.1 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 be 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 Boiler. For either a 420mA/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 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 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.

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Chapter 6 - SAFETY DEVICE TESTING PROCEDURES

6.1 TESTING OF SAFETY DEVICES

Periodic safety device testing is required to ensure that the control system and safety devices are operating as designed. The AERCO control system comprehensively monitors all combustion related safety devices before, during and after the start sequence. The following tests have been chosen to ensure that the system will either not start or will shut-down as intended.

Operating and safety controls should be tested on a regular basis or after a safety device has been serviced or replaced. All testing must conform to local codes such as ASME CSD-1.

NOTE:

MANUAL and AUTO modes 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 sheet metal covers from the unit to perform the following tests.

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 TESTING PROCEDURES THAT CAN RESULT IN ELECTRICAL SHOCK.

6.2 LOW GAS PRESSURE FAULT TEST

1. Referring to Figure 6.1, ensure that the 1/8" NPT ball valve upstream of the SSOV is closed (located at low gas pressure switch).

2. Remove the 1/8" plug from the ball valve, upstream of the safety shutoff valve (SSOV).

3. Install a 0-16" W.C. manometer or W.C. gauge where the 1/8" plug was removed.

4. Slowly open the 1/8" ball valve upstream of the SSOV.

5. Place the unit in Manual Mode and fire the unit at a firing rate between 25% and 30%.

6. While the unit is firing, slowly close the Manual gas shut-off valve located immediately

SAFETY DEVICE TESTING

outside the boiler. The unit should shut down on a LOW GAS PRESSURE fault message at 4.4” W.C. For Benchmark 2.0 Low NOx boilers configured for De-Rated capacity (see para. 2.4.1), the unit should shut down on a LOW GAS PRESSURE fault message at 3.6” W.C.

Figure 6.1

1/8” Pipe Plug Position for Manometer

Installation & Low Gas Pressure Testing

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

8. The unit should restart.

9. Remove manometer and replace 1/8”NPT plug.

NOTE:

After faulting the unit, the fault message will be displayed and the fault indicator light will flash until the CLEAR button is pressed.

6.3 HIGH GAS PRESSURE TEST

1. Start the unit in manual mode and fire between 25% and 30%.

2. Remove either wire # 150 or wire #151 from the high gas pressure switch. See Fig. 6.1.

3. The unit should shut down on a HIGH GAS PRESSURE FAULT.

4. Reconnect the wire previously removed from the high gas pressure switch and depress the CLEAR button.

5. The unit should restart.

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SAFETY DEVICE TESTING

6.4 LOW WATER LEVEL FAULT TEST

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

2. Close 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 it is necessary to vent the unit to aid in draining, the unit’s relief valve may be opened.

4. Drain the unit until the LOW WATER LEVEL fault message is displayed and the FAULT LED flashes.

5. Place the unit in the Manual Mode and raise the firing rate above 25%.

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

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

10. After the shell is full, press the LOW WATER LEVEL RESET button to reset the low water cutoff. Press the CLEAR switch to reset the FAULT LED and clear the displayed error message.

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

6.5 WATER TEMPERATURE FAULT

TEST

1. In the normal operating mode, allow the unit to stabilize at its setpoint.

2. Lower the adjustable temperature limit switch setting to match the displayed OUTLET TEMPERATURE. (See Fig. 6.2)

RESET BUTTON FOR MANUAL RESET TEMPERATURE LIMIT SWITCH

HIGH LIMIT

ADJUSTABLE TEMPERATURE LIMIT SWITCH

MOUNTING PLATE ON SHELL

Figure 6.2

Temperature Limit Switch Setting

3. Once the adjustable limit switch setting is approximately at, or just below, the actual outlet water temperature, the unit should shut down. The FAULT LED should be flashing and the message HIGH WATER TEMP SWITCH OPEN should be displayed. The unit should not start.

4. Reset the adjustable temperature limit switch setting to its prior setting.

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

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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 manual mode and fire at 25% to 30% firing rate.

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 resume running.

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 manual mode and fire at a 25% to 30% firing rate.

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 DELAYED INTERLOCK OPEN. The FAULT LED should be flashing.

5. Once the interlock connection is reconnected, depress the CLEAR button. The unit should start.

6.7 FLAME FAULT TEST

1. Place the ON/OFF switch in the OFF posi- tion.

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

3. Close the manual gas valve located between the SSOV and the Air/Fuel Valve (see Fig.

6.3) and the 1/4” ball valve downstream of the SSOV.

SAFETY DEVICE TESTING

MANUAL GAS SHUT-OFF VALVE

DIFFERENTIAL GAS PRESSURE REGULATOR

Figure 6.3

Manual Gas Shut-Off Valve Location

4. Place the ON/OFF switch in 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 valves previously closed in step 3 and depress 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 safety shut-off valve and the differential regulator.

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

10. Open the valve previously closed in step 8 and depress the CLEAR button. The unit should restart and fire.

6.8 AIR FLOW FAULT TEST

1. Start the unit in manual mode and set the fire rate between 25% and 30%.

2. Once the unit has proved flame, remove either wire #154 or #155 from the blower proof switch (see Fig. 6.4) located on the air/fuel valve.

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

4. Replace the wire previously removed from the blower-proof switch and depress the CLEAR button. The unit should restart.

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SAFETY DEVICE TESTING

Figure 6.4

Blower Proof Switch Location and Wiring

6.9 SSOV PROOF OF CLOSURE SWITCH

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 Safety Shut-Off Valve (SSOV) cover (see Fig. 6.5).

NOTE:

For units with IRI gas trains, the proof of closure switch is located in the downstream SSOV (part no.69005) shown in Fig. 6.5. A second (upstream) SSOV (part no. 69038) is also provided, however it does not contain a regulator and looks physically different. Refer to drawings AP-A-796 and AP-A-801 (De-Rated) in Appendix F for IRI gas trains.

3. Disconnect either wire #149 or #148 from the SSOV.

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

5. Replace the wire previously disconnected and depress the CLEAR button.

6. Start the unit.

7. Disconnect the wire again when the unit reaches the purge cycle.

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

9. Replace the wire previously disconnected and depress the CLEAR button. The unit should restart.

SSOV

ACTUATOR

COVER

SSOV

ACTUATOR

COVER

SCREW

Figure 6.5

SSOV Actuator Cover Screw Location

6.10 PURGE SWITCH OPEN DURING

PURGE

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 pulling it towards you (see Fig. 6.6).

3. Disconnect one of the two wires from the purge position switch (Fig. 6.7) and start the unit.

4. The unit should begin to start, then shut down and display PRG SWITCH OPEN DURING PURGE.

5. Replace the wire on the purge position switch and depress the CLEAR button. The unit should restart.

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SAFETY DEVICE TESTING

6.11 IGNITION SWITCH OPEN DURING

IGNITION

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 (Fig. 6.8) by rotating the cover counterclockwise to unlock it then pulling it towards you.

3. Disconnect one of the two wires from the ignition position switch (Fig. 6.7) and start the unit.

4. The unit should begin to start then shut down and display IGN SWITCH OPEN DURING IGNITION.

Figure 6.6

Air/Fuel Valve Cover Location

5. Replace the wire on the ignition switch and depress the CLEAR button. The unit should restart.

6.12 SAFETY PRESSURE RELIEF VALVE

TEST

Figure 6.7

Air/Fuel Valve Purge and Ignition Switch

Locations

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

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Chapter 7 - MAINTENANCE

7.1 MAINTENANCE SCHEDULE

The unit requires regular routine m aintenance 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 time periods s pecified in Table 7-1.

See Appendix I for complete CSD-1 inspection check list

WARNING!

TO AVOID PERSONAL INJURY, BEFORE SERVICING: (A) DISCONNECT THE AC SUPPLY BY TURNING OFF THE SERVICE SWITCH AND AC SUPPLY CIRCUIT BREAKER (B) SHUT OFF THE GAS SUPPLY AT THE MANUAL SHUT-OFF VALVE PROVIDED WITH THE UNIT (C) ALLOW THE UNIT TO COOL TO A SAFE TEMPERATURE TO PREVENT BURNING OR SCALDING

7.2 SPARK IGNITER

The spark igniter , part number GP-122435-S, is located in the body of the burner (see Fig. 7.1). The igniter may be HOT, therefore care should be exercised. It is easier to remove 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 control panel, 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.

MAINTENANCE

Figure 7.1

Spark Igniter and Flame Detector Location

Top View

CAUTION!

The igniter may be hot

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 build-up is pres ent, clean the igniter using fine emery cloth. Repeated 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 tighten the igniter. A slight snugging up is sufficient. Reconnect the igniter cable.

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

7-1

Page 50

MAINTENANCE

Table 7-1. - Maintenance Schedule

PARAGRAPH ITEM 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 number 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/OFF switch on the control 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)

4. Inspect the detector thoroughly. If eroded, the detector should be replaced. 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.

Spark Igniter (GP-122435-S) Flame Detector

(66006)

Combustion

Adj.

Testing of

Safety Devices

Condensate

Drain Trap

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

*Check Check 1 hr.

See CSD-1

Inspect

Chart in

Appendix

Inspect &

Clean

1 hr.

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.

Figure 7.2

Spark Igniter and Flame Detector Location

Cut-Away View

Labor

Time

20 mins.

7-2

Page 51

MAINTENANCE

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, s uch as ASME CSD1, require that these tests be performed on a scheduled basis. Test schedules must conform to local jurisdictions. The results of the tests should be recorded in a logbook. See Chapter 6Safety Device Testing Procedures.

7.6 BURNER

The burner assembly is located at the top of the unit. The burner assembly may be HOT. Allow the unit to cool sufficiently before removing the burner assembly.

The following parts will be necessary for reassembly after inspection:

81030 Burner Gaskets (Qty=2)

To inspect or replace the burner assembly:

1. Set the ON/OFF switch on the control panel, to the OFF position and disconnect AC power to the unit and turn off the gas supply.

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 cable from the igniter contactor. Unscrew the igniter.

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

6. Disconnect the burner housing from the venturi by removing the six (6) 1/4-20 screws (Fig. 7.3) using a 3/8” wrench.

7. Remove the eight (8) 3/8-16 nuts from the burner flange (see Fig 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.

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 was replaced, f ollow 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”, the extension ring must be reinstalled.

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

16. Check to ensure that the grounding screw was re-installed.

3/8-16 NUTS (8)

GAS INJECTOR

10-32 SCREWS (2)

GROUNDING SCREW

BURNER

BURNER HOUSING

1/4-20 SCREWS (6)

Figure 7.3

Burner Disassembly Diagram

7-3

Page 52

MAINTENANCE

7.7 CONDENSATE DRAIN TRAP 7.8 SHUTTING THE BOILER DOWN FOR

The boiler contains a condensate drain trap connected to the drain line of the exhaust manifold (see Figures 2.4 & 2.5). The trap should be inspected and, if necessary, cleaned to ensure proper operation. Proceed as follows:

1. Disconnect the ex ternal condensate trap by loosening the hose clamps between the trap and the condensate drain connection on the exhaust manifold of the boiler (Figure 2.5).

2. Remove the connections on the inlet and outlet sides of the condensate trap 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 dr ain piping for blockage. If the trap cannot be thoroughly cleaned, replace the trap.

7. Check the condensate drain tapped hole in the exhaust manif old (Figure 2.4) to ensure it is clear of blockage.

8. After the above items have been inspected and thoroughly cleaned, replace the orifice gasket and float in the condensate trap and replace the trap cover.

9. Reass em ble all piping and hose connections to the condensate trap inlet and outlet. Reconnect trap to condensate drain connection on the exhaust manifold.

AN EXTENDED PERIOD OF TIME

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

1. Set the ON/OFF switch on the front panel to the OFF position to shut down the boiler’s operating control.

2. Disconnect AC power from the unit.

3. Close supply and return valves to isolate boiler.

4. Close external gas supply valve.

5. Open relief valve to vent water pressure.

7.9 PLACING THE BOILER BACK IN

SERVICE AFTER A PROLONGED SHUTDOWN

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

1. Review installation requirements as shown in Chapter 2

2. Inspect all piping and connection to the unit

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

4. Perform initial startup per Chapter 4

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

7-4

Figure 7.4

External Condensate Trap

Page 53

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 Series 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 54

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

AIRFLOW FAULT

DURING IGNITION

AIRFLOW FAULT

DURING PURGE

AIRFLOW FAULT

DURING RUN

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

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.

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

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 airflow switch and inspect for signs of blockage, clean or replace as necessary.

4. Measure the airflow 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.

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.

1. Check combustion blower for signs of excessive heat or high current draw 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 airflow switch and inspect for signs of blockage, clean or replace as necessary.

4. Measure the airflow 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.

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

-2

Page 55

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

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

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.

8-3

Page 56

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

(continued) 7. Defective Differential Pressure

Regulator

8. Carbon or other debris on Burner

FLAME LOSS

DURING RUN

HEAT DEMAND

FAILURE

HIGH EXHAUST

TEMPERATURE

HIGH GAS

PRESSURE

1. Worn Flame Detector or cracked ceramic.

2. Defective Differential Regulator.

3. Poor combustion calibration.

4. Debris on burner.

5. Blocked condensate drain.

1. The Heat Demand Relays on the Ignition/Stepper board failed to activate when commanded

2. Relay is activated when not in Demand

1. Defective exhaust sensor.

2. Carboned heat exchanger due to incorrect combustion calibration

1. Incorrect supply gas pressure.

2. Defective SSOV Supply Regulator.

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 4.8” W.C. (see para. 4.3, step 8), the SSOV Supply Regulator may be defective. For Benchmark 2.0 Low NOx boilers configured for De-Rated capacity (see para. 2.4.1), if gas supply pressure downstream of the SSOV cannot be lowered to

F, check

8-4

Page 57

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

continued 2. continued 3.7” W.C.(see para.4.3, step 8) the SSOV Supply Regulator may be

3. Defective High Gas Pressure Switch

4. Gas pressure snubber not installed.

HIGH WATER TEMP

SWITCH OPEN

HIGH WATER

TEMPERATURE

IGN BOARD

COMM FAULT

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 Temperature Switch setpoint.

6. Boiler Management System PID or other settings not correctly setup.

7. No interlock to boiler or BMS to disable boiler(s) in event that system pumps have failed.

8. System flow rate changes are occurring faster than boilers can respond.

1. See HIGH WATER TEMPERATURE SWITCH OPEN.

2. Temp HI Limit setting is too low.

1. Communication fault has occurred between the PMC board and Ignition/Stepper (IGST) board

defective.

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. Make sure 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.

8-5

Page 58

TROUBLESHOOTING

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

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.

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).

8-6

Page 59

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

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

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

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 at least 5.3” WC (5.5” WC for IRI). For Benchmark 2.0 Low NOx boilers configured for De-Rated capacity (see para. 2.4.1), ensure gas pressure upstream of the supply gas regulator, with the unit firing, is at least 4.0” W.C. (4.2” W.C. for IRI).

2. Measure gas pressure at the low gas pressure switch, if it is greater than 4.4” WC measure continuity across the switch and replace if necessary. For Benchmark 2.0 Low NOx boilers configured for De-Rated capacity (see para. 2.4.1), if measured gas pressure at the low gas pressure switch is greater than 3.6” 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.

8-7

Page 60

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

continued 2. Defective or shorted switch.

3. Switch wired incorrectly.

4. Defective Power Supply Board or fuse

5. Defective IGST Board

PRG SWTCH OPEN

DURING PURGE

OUTDOOR TEMP

SENSOR FAULT

REMOTE SETPT

SIGNAL FAULT

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.

6. 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.

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.

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.

6. 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.

8-8

Page 61

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

continued 3. Control Box signal type selection

switches not set for correct signal type (voltage or current).

RESIDUAL

FLAME

SSOV FAULT

DURING PURGE

SSOV FAULT

DURING RUN

SSOV RELAY

FAILURE

SSOV

SWITCH OPEN

STEPPER MOTOR

FAILURE

1. SSOV not fully closed.

2. Defective Flame Detector.

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.

1. 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. Check open/close indicator window of Safety Shut-Off Valve (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.

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.

8-9

Page 62

TROUBLESHOOTING

TABLE 8-1. BOILER TROUBLESHOOTING – Continued

FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION

continued 4. Defective Air/Fuel Valve stepper

motor.

5. Defective Power Supply Board or fuse.

6. Defective IGST Board

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

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.

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

8-10

1. IGST and Power Supply Boards outdated.

1. Open the 1/4” Ball Valve downstream of the SSOV.

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

3. Close the 2” Ball Valve downstream of the Differential Regulator and the 1/4” Ball Valve downstream of the SSOV. 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 that the Damping Orifice is installed on the SSOV/ Regulator Actuator (Figure 8.3).

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

Page 63

TROUBLESHOOTING

HIGH GAS PRESSURE SWITCH

GAS PRESSURE SNUBBER

Figure 8.1

High Pressure Gas Switch & Gas Pressure

Damping Orifice Location

Snubber Locations

Figure 8.3

Staged Ignition Solenoid Location

8-11

Figure 8.2

Page 64

Page 65

APPENDIX A

BOILER MENU ITEM DESCRIPTIONS

MENU LEVEL & OPTION DESCRIPTION

OPERATING MENU Active Setpoint This is the setpoint temperature to which the

control is operating 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 Outdoor Temp Displayed only if an outdoor sensor is installed and

enabled in the Configuration Menu. Fire Rate In Indicates desired input fire rate. This will 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

999,999. Fault Log Displays information on the last 9 faults.

A-1

Page 66

APPENDIX A

MENU LEVEL & OPTION DESCRIPTION

BOILER MENU ITEM DESCRIPTIONS - Continued

SETUP MENU

Password Allows password to be entered.

Language English only. Time Displays time from 12:00am to 11:59pm. Date Displays dates from 01/01/00 to 12/31/99 Unit of Temp Permits selection of temperature displays in

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

Baud Rate Allows communications Baud Rate to be set (2400

Software Version Identifies the current software version of the control

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

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

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

to 19.2K). Default is 9600.

box. CONFIGURATION MENU Internal Setpoint Allows internal setpoint to be set . Default is 130°F. Unit Type Allows selection of Boiler or Water Heater. Default

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

Boiler Mode It allows selection of: Constant Setpoint, Remote

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

Bldg Ref Temp

is Boiler.

MBTU.

Setpoint, Direct Drive, Combination, or Outdoor

Reset Mode. Default is Constant Setpoint Mode.

used when operating in the Remote Setpoint, Direct

Drive or Combination Mode. The factory default is

4-20 mA/1-5V.

Allows the building reference temperature to be set

when operating a boiler in the Outdoor Reset Mode.

Default is 70°F.

A-2

Page 67

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 in the Configuration

Menu, this menu item allows the system start

temperature to be set from 30°F 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 220°F). Default is 200°F. Temp Hi Limit Used to set the maximum allowable outlet

temperature (40°F to 240°F). Any temperature

above this setting will turn off the unit. The

temperature must then drop 5°F below this setting

to allow the unit to run. Default Temp 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 Can be set to allow this output to monitor Setpoint,

Outlet Temperature, Fire Rate Out or be set to OFF.

Default is OFF. Lo Fire Timer Specifies how long (2 to 120 sec.) to remain in the

low fire position after ignition, before going to the

desired output. Default is 2 sec.

A-3

Page 68

APPENDIX A

BOILER MENU ITEM DESCRIPTIONS - Continued

MENU LEVEL & OPTION DESCRIPTION

Setpt Limiting Allows Setpoint Limiting to be enabled or disabled.

Default is disabled. Setpt Limit Band If Setpoint Limiting is enabled, this menu item allows

the Setpt Limit Band to be set from 0°F to 10°F.

Default is 5°F. TUNING MENU Prop Band Generates a fire rate based on the error that exists

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

Derivative Time This value (0.0 to 2.00 min.) responds to the rate of

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

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%. Default is 70°F.

error, to add or subtract from the output each minute

to move towards the setpoint. Gain is adjustable

from 0.00 to 2.00. Default is 1.00.

change of the setpoint error. This is the time that

this action advances the output. Default is 0.0 min.

Factory Default values.

A-4

Page 69

MESSAGE DESCRIPTION

DISABLED

HH:MM pm MM/DD/YY

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

DEMAND DELAY

XX sec

PURGING

XX sec

IGNITION TR IAL

XX sec

FLAME PROVEN

WARMUP

XX sec

WAIT Prompts the operator to wait.

APPENDIX B

STARTUP, STATUS AND FAULT MESSAGES

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 70

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

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. 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 71

APPENDIX B

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 72

Page 73

Temperature Sensor Resistance Chart

(Balco)

APPENDIX C

C-1

Page 74

Page 75

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

INDOOR/OUTDOOR RESET RATIO CHARTS

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

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 76

APPENDIX D

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

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 77

APPENDIX D

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

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 78

APPENDIX D

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 79

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 1.0 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 Off

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 80

Page 81

APPENDIX F

F-1

Page 82

APPENDIX F

F-2

Page 83

APPENDIX F

F-3

Page 84

APPENDIX F

F-4

Page 85

APPENDIX F

F-5

Page 86

APPENDIX F

F-6

Page 87

APPENDIX F

TEST

COCK

HIGH GAS PRESS.

SWITCH

(INSTALL

1/8" NPT PLUG

P/N: 61002-12

MANOMETER HERE)

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

AP-A-800

FM GAS TRAIN

APPD.CHKD.

SIZESCALE

DATE REV.

DE-RATED OPTION)

CZ 021406

BENCHMARK2.0 LOW NOx

2" SAFETY

SHUT-OFF

GAS VALVE

P/N 124136

SWITCH

P/N: 61002-11

LOW GAS PRESS.

2" SAFETY SHUT-OFF

VALVE ACTUATOR w/

REGULATOR

P/N 64048

NTS

(1.75 MIL. BTU/HR INPUT

DWN.BY

2" NPT DIFFERENTIAL GAS

PRESSURE REGULATOR

P/N 123541

BOILER BOUNDARY

2" NPT

FULL PORT

P/N: 123540

BALL VALVE

TO AIR-FUEL VALVE ASS'Y

2"-SCH.40 PIPE

F-7

Page 88

APPENDIX F

F-8

Page 89

APPENDIX F

F-9

Page 90

APPENDIX F

F-10

Page 91

APPENDIX F

F-11

Page 92

APPENDIX F

F-12

Page 93

LEGEND

ISOLATION VALVE

Y STRAINER

UNION

PRESSURE &

BALANCING VALVE

P&T

TEMPERATURE GAUGE

AT MAXIMUM BTU/HR INPUT,

APPENDIX G

REV

SD-A-671

INTERNATIONAL, INC.

NORTHVALE, NJ 07647

BENCHMARK 2 MIL. BTU LOW NOx

021506

GAS FIRED BOILER

SINGLE UNIT INSTALLATION

DATE

NTS

APPD.

DWN.BY

SCALE

GAS SUPPLY

AERCO

* 2" MANUAL

SHUTOFF

VALVE

MAINTAIN MINIMUM GAS PRESSURE AT

5.3" W.C.(FM GAS TRA IN); 5.5" W.C. (IRI).

MAX. GAS PRESSURE = 2.0 PSIG. (SEE NOTE 6)

DIRT TRAP

AUTOMATIC

SYSTEM

PUMP

CHECK

VALVE

HEATING

RELIEF VALVE (TYP.)

AIR VENT

(TYP.)

SYSTEM

AIR

SUPPLY

SEPARATOR

WATER

SUPPLY

REDUCING

PRESSURE

FILL VALVE

P&T

LINE SIZE BYPASS

BACKFLOW PREVENTER

(SEE NOTE 7)

Diagram 1

EXPANSION TANK

DIAPHRAGM TYPE

MAINTAIN A REGULATED

5.3" W.C. (FM), 5.5 W.C. (IRI)

GAS PRESSURE AT MAX

BTU/HR INPUT

SYSTEM

RETURN

HEATING

DRAIN TRAP

* CONDENSATE

1-1/2" NPT

DRAIN CONN.

GAS SUPPLY

DRIP TRAP

* 2" MANUAL

SHUTOFF

VALVE

ELECTRIC CONNECTIONS (SERVICE SWITCHES, CONDUIT BOXES) SHOULD LIKEWISE

BE 6'' AWAY FROM SIDE PANELS.

DOWNSTREAM OF THE 2" MANUAL SHUTOFF VALVE TO BRING THE GAS PRESSURE DOWN TO 2.0 PSIG.

(TO BOILER)

NOTES:

1) FOR ACTUAL SIZES AND LOCATIONS OF PIPING AND OTHER CONNECTIONS TO THE BOILER, SEE DIMENSIONAL DRAWING (AP-A-739).

2) SHELL DRAIN VALVE AND CONDENSATE DRAIN TRAP SHOULD BE ARRANGED TO PERMIT THE FLUIDS TO DRAIN

FREELY, BY GRAVITY, TO A CONVENIENT FLOOR DRAIN. RELIEF VALVE SHOULD BE PIPED VERTICALLY TO A

FITTINGS TO PREVENT INTERFERENCE WITH REMOVAL OF BOILER PANELS AND COVERS. ALL PIPING AND

4) LOCATE WATER INLET AND OUTLET FITTINGS (i.e. UNIONS, ELBOWS, ETC.) A MINIMUM OF 6'' FROM BOILER

3) ALL (*) ITEMS ARE INCLUDED SEPARATELY IN SHIPMENT FROM FACTORY.

HEIGHT 18'' ABOVE FLOOR.

5) THIS IS A TYPICAL INSTALLATION DRAWING. LOCAL CODES AND AUTHORITIES SHOULD BE CONSULTED.

6) WHEN AVAILABLE GAS PRESSURE IS GREATER THAN 2.0 PSIG, A LOCK-UP STYLE REGULATOR MUST BE INSTALLED

SEE DIAGRAM 1

7) A GAS REGULATOR IS MANDATORY FOR THE STATE OF MASSACHUSETTS, REGARDLESS OF SUPPLY PRESSURE.

G-1

Page 94

APPENDIX G

REV

LEGEND

RELIEF

Y STRAINER

VALVE (TYP.)

ISOLATION VALVE

UNION

BALANCING VALVE

PRESSURE &

P&T

TEMPERATURE GAUGE

* 2" MANUAL

SHUTOFF

VALVE

AT MAXIMUM BTU/HR INPUT,

MAINTAIN MINIMUM GAS

PRESSURE AT 5.3" W.C.

(FM GAS TRAIN); 5.5" W.C.(IRI).

MAX. GAS PRESSURE=2.0 PSIG.

(SEE NOTE 6)

P&T

DIRT TRAP

P&T

HEATING

SYSTEM

RETURN

GAS SUPPLY

SD-A-672

INTERNAT IONAL, INC.

NORTHVALE, NJ 07647

021506

GAS FIRED BOILER

DATE

MULTIPLE UNIT INSTALLATION

BENCHMARK 2 MIL. BTU LOW NOx

AERCO

NTS

APPD.

DWN.BY

SCALE

CHECK

SYSTEM

AUTOMATIC

PUMP

VALVE

(TYP.)

SYSTEM

HEATING

AIR VENT

SUPPLY

AIR

SEPARATOR

WATER

SUPPLY

REDUCING

PRESSURE

FILL VALVE

DRAIN TRAP

* CONDENSATE

1-1/2" NPT

DRAIN CONN.

EXPANSION TANK

DIAPHRAGM TYPE

GAS SUPPLY

DRIP TRAP

LINE

SIZE

BACKFLOW PREVENTER

BYPASS

(SEE NOTE 7)

Diagram 1

MAINTAIN A REGULATED

5.3" W.C. (FM), 5.5 W.C. (IRI)

GAS PRESSURE AT MAX

BTU/HR INPUT

* 2" MANUAL

SHUTOFF

VALVE

(TO BOILER)

NOTES:

CONVENIENT FLOOR DRAIN. RELIEF VALVE SHOULD BE PIPED VERTICALLY TO A HEIGHT 18'' ABOVE FLOOR.

2) SHELL DRAIN VALVE AND CONDENSATE DRAIN TRAP SHOULD BE ARRANGED TO PERMIT THE FLUIDS TO DRAIN FREELY, BY GRAVITY, TO A

1) FOR ACTUAL SIZES AND LOCATIONS OF PIPING AND OTHER CONNECTIONS TO THE BOILER, SEE DIMENSIONAL DRAWING (AP-A-739).

3) ALL (*) ITEMS ARE INCLUDED SEPARATELY IN SHIPMENT FROM FACTORY.

4) LOCATE WATER INLET AND OUTLET FITTINGS (i.e. UNIONS, ELBOWS, ETC.) A MINIMUM OF 6'' FROM BOILER

ELECTRIC CONNECTIONS (SERVICE SWITCHES, CONDUIT BOXES) SHOULD LIKEWISE BE 6" AWAY FROM SIDE PANELS.

FITTINGS TO PREVENT INTERFERENCE WITH REMOVAL OF BOILER PANELS AND COVERS. ALL PIPING AND

5) THIS IS A TYPICAL INSTALLATION DRAWING. LOCAL CODES AND AUTHORITIES SHOULD BE CONSULTED.

6) WHEN AVAILABLE GAS PRESSURE IS GREATER THAN 2.0 PSIG, A LOCK-UP STYLE REGULATOR MUST BE INSTALLED

SEE DIAGRAM 1

DOWNSTREAM OF THE 2" MANUAL SHUTOFF VALVE TO BRING THE GAS PRESSURE DOWN TO 2.0 PSIG.

7) A GAS REGULATOR IS MANDATORY FOR THE STATE OF MASSACHUSETTS, REGARDLESS OF SUPPLY PRESSURE.

G-2

Page 95

APPENDIX G

G-3

Page 96

APPENDIX G

G-4

Page 97

APPENDIX G

G-5

Page 98

Page 99

APPENDIX H

H-1

Page 100

APPENDIX H

H-2