Reznor RCB060 Service Manual

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Page 1

Form O-MAPSIII&IV Cabinets A/B/C (Version B.4)



CQS

Obsoletes O-MAPSIII Cabinets A/B/C (Version B.3)

Operation / Maintenance / Service

Applies to: Cabinet Sizes A, B, and C

™

of MAPS®III Models RCB, RDB,

RDCB, RDDB, RECB, REDB and

MAPS®IV Models RCC, RDC,

RDCC, RDDC, RECC, REDC

CQS

MAPS® Cabinet

Sizes A, B, and C

R-410A

Refrigerant

DANGER

This unit contains R-410A high pressure refrigerant. Hazards exist that could result in personal injury or death. Installation, maintenance, and service should

only be performed by an HVAC technician qualied in R-410A refrigerant and

using proper tools and equipment. Due to much higher pressure of R-410A refrigerant, DO NOT USE service equipment or tools designed for R22 refrigerant.

IMPORTANT: Do not release refrigerant to the atmosphere! If required service procedures include the adding or removing of refrigerant, the service technician must comply with all federal, state and local laws. The procedures discussed

in this manual should only be performed by a qualied HVAC technician.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 1

Page 2

Table of Contents

1.0 General ....................................................2-3

2.0 Maintenance Requirements ..................3-6

2.1 Maintenance Schedule.....................................4

2.2 Control Locations ............................................. 5

2.3 Cross-Reference of Models and

Cabinet Sizes A, B, and C ..............................6

3.0 Maintenance & Service Procedures ...6-21

3.1 Filters ..............................................................6

3.2 Drive Components ...........................................7

3.3 Condenser Fans...............................................8

3.4 Coil Maintenance .............................................8

3.5 Check Refrigerant Pressure & Temperatures

(subcooling and superheat) ............................. 9

3.6 Compressor Operation, Maintenance, and

Replacement.................................................. 11

3.7 Thermostatic Expansion Valves ..................... 19

3.9 Other Controls ................................................ 20

3.8 Optional Dampers and Damper Controls ....... 20

1.0 General

This booklet includes operation, maintenance, and service information for Cabinet Sizes A, B, and C of the MAPS® III and MAPS® IV Models listed below. Before beginning any procedure, carefully review the information, paying particular attention to the warnings. Handling of refrigerant should only be performed by a certied HVAC technician with knowledge of the requirements of R-410A refrigerant and in compliance with all codes and requirements of authorities having jurisdiction.

The instructions in this manual apply to the following MAPS® Models in Cabinet A, B, and C Sizes and Model JHUP 250 and 300 duct furnace curb option.

4.0 Gas Heat Section Maintenance -

RDCB, RDCC, RDDB, RDDC .............21-30

4.1 Heat Exchanger, Burner, and Venter..............21

4.2 Heat Section Controls .................................... 25

4.3 Gas Train........................................................26

4.4 Other Gas Heat Section Controls / Sensors ..30

5.0 Electric Heat Section Maintenance -

RECB, RECC, REDB, REDC ..............30-31

6.0 Energy Recovery Module,

Option ER1 ..............................................31

7.0 Troubleshooting .................................32-39

7.1 Troubleshooting - Refrigeration (All Models) ..32

7.2 Compressor Digital Controller

Troubleshooting - all MAPS® IV Models.........33

7.3 Troubleshooting the Heat Section .................34

INDEX .............................................................40

NOTE: To conrm that this

booklet is applicable, see list of Model and Cabinet Sizes in Paragraph 2.3, page 6.

Form O-MAPSIII&IV Cabinets A/B/C, Page 2

MAPS

Model

III MAPS®IV

RCB RCC

RDCB RDCC

RECB RECC

RDB RDC

RDDB RDDC

REDB REDC

JHUP

System Description (MAPS®III models have staged cooling; MAPS®IV models have modulating cooling.)

Makeup Air Cooling Packaged System, 1500-9000 CFM

Makeup Air Cooling Packaged System, 1500-9000 CFM, with Gas Heat Section (100-700 MBH)

Makeup Air Cooling Packaged System, 1500-9000 CFM, with Electric Heat Section (10- 88 kw)

Makeup Air Cooling and Re-heat Pump Reheat Cycle Packaged System, 1500-9000 CFM

Makeup Air Cooling and Re-heat Pump Reheat Cycle Packaged System, 1500-9000 CFM, with a Gas Heat Section (100-700 MBH)

Makeup Air Cooling and Re-heat Pump Reheat Cycle Packaged System, 1500-9000 CFM, with Electric Heat Section (10 - 88 kw)

Optional Curb Section with 250 or 300 MBH Gas-Fired Duct Furnace installed with a Model RDCB, RDCC, RDDB or RDDC with a Size 250 or 700 Heat Section to provide 500 or 1000 MBH heating

Page 3

Denitions of Hazard

Intensity Levels used in this Manual

There are warning labels on the unit and throughout this manual. For your safety, comply with all warnings during installation, operation, and service of this system. See

denitions of Hazard Intensity Levels of warnings below.

HAZARD INTENSITY LEVELS

1. DANGER: Failure to comply will result in severe personal injury or death and/or property damage.

2. WARNING: Failure to comply could result in severe personal injury or death and/or property damage.

3. CAUTION: Failure to comply could result in minor personal injury and/or property damage.

2.0 Maintenance Requirements

To ensure long life and satisfactory performance, a system that is operating under normal conditions should be inspected according to the Maintenance Schedule in Paragraph 2.1. If in an area where an unusual amount of dust or soot or other impurities are present in the air, more frequent inspection is recommended.

Refer to the illustration in FIGURE 1 and follow the instructions in the referenced paragraphs to maintain this equipment. Maintenance requirements apply to all Models and Sizes unless noted.

performed by a qualied HVAC technician familiar with

R-410A refrigerant.

WARNING

Lock power OFF before performing any maintenance procedure (except where power is required such as checking refrigerant pressure and temperature). Lock disconnect switch in OFF position. If the system has a gas heat section, when you turn off the power supply, turn off the gas. See Hazard Levels above.

If replacement parts are required, use only factory-

authorized parts. For information, go to

www.ReznorHVAC.com or call (800)-695-1901.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 3

Page 4

2.0 Maintenance Requirements (cont'd)

2.1 Maintenance

Schedule

Important NOTE:

If equipped with an optional energy recovery module, refer to Form I-MAPSIII&IV-ER for enthalpy wheel maintenance instructions

Monthly

□ Inspect lters; clean or replace as needed. See Paragraph 3.1.

□ Inspect the condensate drain; clean as needed. For information, see the

installation manual, Form I-MAPSIII&IV, Paragraph 6.2.

Semi-Annually

□ Inspect the unit blower and belts. Check belts for tension, wear, and alignment.

Adjust or replace as needed. Clean dirt from blower and motor. See Paragraph

3.2.

Annually

NOTE: Redo the cooling startup procedures when the cooling season begins. Refer

to Startup instructions in the installation manual, Form I-MAPSIII&IV, Paragraph 10.0.

All Models - Beginning of the cooling season or more frequently in year-round cooling climate:

□ Inspect the wiring for any damaged wire. Replace damaged wiring.

□ Inspect the condensate drain pan. Clean the coil cabinet, clean the drain pan,

and ll the trap.

□ Inspect/clean condenser fans. See Paragraph 3.3.

□ Inspect/clean all coils. See Paragraph 3.4.

□ Check compressor operation. See Paragraph 3.6.

□ Check refrigerant pressure and temperatures (superheat and subcool). These

checks are done when the system is operating. See Paragraph 3.5.

Models RDCB, RDCC, RDDB, & RDDC with a gas heat section (beginning of the heating season) - See Paragraph 4.0:

NOTE: A MAPS® B cabinet with 500 MBH of heat is a Size 250 gas heat section plus an optional Model JHUP curb duct furnace. A MAPS® C cabinet with 1000 MBH of heat is a Size 700 gas heat section plus an optional Model JHUP curb duct furnace. The same maintenance procedures apply to the duct furnaces.

□ Clean all dirt and grease from the combustion air openings and the venter

assembly.

□ Check the heat exchanger, burner, and venter for scale, dust, or lint

accumulation. Clean as needed.

□ Check the gas valves to ensure that gas ow is being shutoff completely.

Models RECB, RECC, REDB, & REDC with an electric heat section (beginning of the heating season) - See Paragraph 5.0:

Form O-MAPSIII&IV Cabinets A/B/C, Page 4

□ Check wiring connections.

□ Check the heat section and elements for dust or lint accumulation. Carefully

clean as needed.

Page 5

2.2 Control Locations

Controller

Display

(BacView)

Controller

Reheat

Board

Combustion

Air Proving

Switch

(RDCB/RDCC/

RDDB/RDDC)

Air Proving Switch

Power Supply

Ignition

Board

(RDCB/RDCC/

RDDB/RDDC)

Relay or Sequencer (RDCB/RDCC/ RDDB/RDDC)

Control

Expander

Option BHB6

Dirty Filter Switch or Differential Pressure Gauge

Low Voltage Panel - Cabinet C

Optional Control Block(s)

FIGURE 1 - Showing Access (panels removed) and High and Low Voltage Control Locations (including control options)

Condenser Section

Compressors

Tubing Access

Heat Section

(Gas illustrated)

High Voltage Panels

Cabinets A & B

Digital Controller

- MAPS IV only

Control

Transformers

Contactor,

Condenser Fan

Contactor,

Compressor A

Fuse & Fuse

Holder

Contactor,

Compressor B Contactor, Compressor C (below “B”, behind the transformer)

Cabinet C

Contactor,

Compressor B

Optional

Transformer

Control

Transformers

Digital Controller

- MAPS IV only

Fuse & Fuse

Holder

Contactor, Compressor DH

Phase Monitor or Motor Saver

Dampers

Blower Section with Bottom Discharge

Two Low Voltage Panels A&B Cabinets (top right)

or Low Voltage Panel -

C Cabinet (bottom right)

Phase Monitor or Motor Saver

Distribution Blocks

Grounding Lug

Contactor or Starter and Overload, Blower Motor

Contactor, Compressor DH

Optional Transformer

Contactor, Compressor A

Contactor, Condenser Fan

Contactor, Compressor C

Contactor or Starter and Overload, Blower Motor Distribution Blocks Grounding Lug

Optional Transformer

Slide-out Filter Rack

Reheat

Compressor

Evaporator Coil Section (with slide out drain pan)

Primary Low Voltage Layout - Cabinets A & B

Controller

Display

(BacView)

Controller

Optional

Plugin Card

Optional

Differential

Pressure

Switch

Combustion

Air Proving

Switch

(RDCB/RDCC/

RDDB/RDDC)

Air Proving

Switch

Venter Motor

Capacitor

(RDCB/RDCC/

RDDB/RDDC)

Secondary Low Voltage Layout -

Cabinets A & B

Optional

Control

Expander

Optional

Reheat

Board

Sequencer (RDCB/RDCC/ RDDB/RDDC)

Ignition Board (RDCB/RDCC/ RDDB/RDDC)

Optional Control Block(s)

Power Supply

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 5

Page 6

2.0 Maintenance Requirements (cont'd)

2.3 Cross-Reference of Models and Cabinet Sizes A, B, and C

DX Cooling Models RCB and RCC and DX with Reheat Models RDB and RDC

Model

RCB

RCC

060

078 --

090

118 120

136 --

160

186 --

200

190

216 --

298

410

Model

RDB

RDC

084

102 --

114

142 144

162 --

184

-- 196

210 --

222 --

224 --

236

-- 257

248

262

272 --

288 --

354

370

468

482

3.0 Maintenance and Service Procedures

Cabinet Size A B C

Model Sizes 060/078/084/102 090/114/11//120/136/142/144/162 All Cabinet B All Cabinet C

Filter Description Opt Qty Size P/N Qty Size P/N Qty Size P/N Qty Size P/N

2” Pleated Disposable AW 11 1 20x25x2 104113

4” Pleated Disposable, MERV 8

4” Pleated Disposable, MERV 13

2” Permanent Aluminum AW9 1 20x25x2 101623

4” Permanent Aluminum AW20 2 20x25x2 101623

Model RDCB, RDDB, RDCC, and RDDC by Cabinet Size and Gas Heat Section Size

Model

RDCB

RDCC

-100 -150 -200 -250 -300 -400 -500 -600 -700 -800 -1000

060

Cabinet

078 --

Size

118 120

136 --

186 --

216 --

Model

RDDB

102 --

142 144

Size

162 --

-- 196

210 -222 --

224 --

-- 257

272 -288 --

* A MAPS® B Cabinet with 500 mbh of gas heat is a Size 250 mbh heat section plus an Option JH25 curb with a 250 mbh

duct furnace.

A A A -- -- -- -- -- -- -- --

A A A B B B* -- -- -- --

090

A A A B B B* -- -- -- --

160

-- -- -- B B B* -- -- -- --

200

-- -- -- B B B* -- -- -- --

190

-- -- -- -- -- C C C C -- C**

298

-- -- -- -- -- C C C C -- C**

410

-- -- -- -- -- C C C C -- C**

Model

RDDC

-100 -150 -200 -250 -300 -400 -500 -600 -700 -800 -1000

084

A A A -- -- -- -- -- -- -- -A A A B B -- -- -- -- -- --

114

A A A B B -- -- -- -- -- --

-- A A B B -- -- -- -- -- --

184

-- -- -- B B -- -- -- -- -- --

236

-- -- -- B B -- -- -- -- -- --

248

-- -- -- -- -- C C C C -- C**

262

-- -- -- -- -- C C C C -- C**

354

-- -- -- -- -- C C C C -- C**

370

-- -- -- -- -- C C C C -- C**

468

-- -- -- -- -- C C C C -- C**

482

-- -- -- -- -- C C C C -- C**

Gas Heat Section Size

Model RECB, REDB, RECC, and REDC by Electric Heat Module and Cabinet Size

Model RECB

060

078 --

090 118 120 136 --

160 186 --

200

190 216 --

298

410

Model REDB

084 102 --

114 142 144 162 --

184

-- 196 210 -222 -224 --

236

-- 257

248

262 272 -288 --

354

370

468

482

Model RECC

-10S -15S -20S -24S -15 -20 -25 -30 -35 -39 -50 -60 -75 -88 A A A A A A A A A A -- -- -- --

-- A A A A B A A B A B B B --

-- A A A A B A A B A B B B B

-- -- -- -- B B B B B B B B B B

-- -- -- -- -- B B B B B B B B B

-- -- -- -- -- -- -- -- -- C C C C C

Model REDC

-10S -15S -20S -24S -15 -20 -25 -30 -35 -39 -50 -60 -75 -88 A A A A A B A A B A B B B --

-- A A A A B A A B A B B B B

-- -- -- -- A B A A B A B B B B

-- -- -- -- B B B B B B B B B B

-- -- -- -- -- B B B B B B B B B

-- -- -- -- -- -- -- -- -- C C C C C

Electric Heat Section

** A MAPS® C Cabinet with 1000 mbh of gas heat is a Size 700 mbh heat section plus an Option JH30 curb with a 300 mbh duct furnace.

3.1 Filters

The lter section is equipped with a slide out lter rack and 2 or 4 inch, pleated disposable or permanent aluminum lters. To remove lters, open the door and slide lters out. Replacement lters are listed in the table below. Do not use any other type of lters.

AW21 1 20x25x4 205791

AW24 1 20x25x4 256663

If equipped with permanent aluminum lters, remove the lters, wash, rinse, allow to

dry, and slide them back in the cabinet.

If equipped with pleated disposable lters, replace dirty lters. Exposure to humid makeup air can accelerate lter degradation. Systems with disposable lters require more frequent lter inspection.

2 16x20x2 104110 2 20x20x2 104111 2 16x20x4 211127 2 20x20x4 205790 2 16x20x4 256665 2 20x20x4 256662 2 16x20x2 101620 2 20x20x2 101621 4 16x20x2 101620 4 20x20x2 101621

4 20x25x2 104113 6 20x25x2 104113

4 20x25x4 205791 6 20x25x4 205791

4 20x25x4 256663 6 20x25x4 256663

4 20x25x4 101623 6 20x25x2 101623

8 20x25x2 101623 12 20x25x2 101623

Dirty Filter Switch (Options BE16 and BE18)

If equipped with a dirty lter switch or gauge, check the condition of the sensing tubes

to be sure that they are not blocked. Check the wiring connections. To set a new switch (Option BE18), see Installation Form I-MAPSIII&IV, Paragraph 8.3, Replacement switch is P/N 105507.

Form O-MAPSIII&IV Cabinets A/B/C, Page 6

Page 7

Filter

Clamp

Filter

Wing Screw,

P/N 205707,

and Retainer,

P/N 205709

(2 each)

Filter

Filter Clamps attach with Wing Screws P/N 205707

Filter

16x20x1

Filter

16x20x1

Filter

16x20x1

Filter

16x25x1

Filter

16x25x1

Filter

16x25x1

Filter

16x20x1

Filter

16x20x1

Filter

16x20x1

Inlet View

  

 

   

Permanent Filters in the Outside Air Hood

If equipped with an outside air hood, there are 1" permanent, aluminum lters at the entrance of the hood. The lters act as a moisture eliminator and bird screen. See FIG- URE 2A or 2B. When inspecting the inlet air lters, inspect the outside air hood lters. If cleaning is needed, remove the lters, clean, rinse, dry and re-install.

NOTE: If it is more convenient to keep an extra clean set of lters, lter sizes and part numbers are shown in the illustration.

FIGURE 2A - Removing Filters from Outside Air Hood

1" Permanent Aluminum Filters for Outside Air

Cabinet Sizes A and B with Option AS16 Outside Air Hood

(Does not apply if system includes Option PE power exhaust; see below.)

All Cabinet Size C with either Outside Air Hood Option AS16 or AS19

Hood are listed by Cabinet Size A, B, or C (see cross-reference, page 6)

*A - (4) 16 x 20, P/N 101607 *B - (4) 16 x 25, P/N 101609

C - (3) 16 x 25, P/N 101609;

(6) 16 x 20, P/N 101607

* Apply only to Cabinet Size A and B with outside

air hood Option AS16

Instructions: Remove lters by loosening the wing screws and sliding the lter

clamp(s). Clean with soap and water, allow to dry, and replace. If it is more convenient

to keep an extra clean set of lters, quantities, lter sizes, and part numbers are listed.

FIGURE 2B - Removing Filters from Option AS19 Outside Air Hood Installed on a Cabinet Size A or B with power exhaust Option PE1 or PE2

Instructions: 1) Remove the four screws as illustrated. Lower the tray.; 2) Pull out lters. Clean with soap and water. Allow to dry.; 3) Slide clean dry lters into tray.;

4) Re-position tray and replace screws. 1" Aluminum Filters: **A - (4) 18 x 20, P/N 194903; **B - (4) 20 x 25, P/N 101610

** Apply only to Cabinet Size A and B with outside air hood Option AS19.

Filters in an Optional Energy Recovery Module

*See cross-reference of MAPS® Models by Cabinet Size A, B, or C on page 6.

3.2 Drive Components

CAUTION: If the blower is unused for more than three months, bearings

with a grease tting

should be purged with new grease

prior to startup.

If equipped with an energy recovery module (Option ER1A, ER1B, or ER1C), check

both inlet and exhaust lters. Replace as needed.

Cabinet

Size *

A Pleated 20x25x2 2 104113 Pleated 20x25x2 2 104113

Inlet Air Filters (Merv 8) Exhaust Air Filters (Merv 8)

Filter Type & Size Qty P/N Filter Type & Size Qty P/N

Pleated 16x25x2 2 104112 Pleated 16x25x2 2 104112 Pleated 12x25x2 2 114320 Pleated 12x25x2 2 114320 Pleated 16x25x2 2 104112 Pleated 16x25x2 2 104112 Pleated 20x25x2 2 104113 Pleated 20x25x2 2 104113 Pleated 16x16x2 1 104109 Pleated 16x16x2 1 104109 Pleated 16x20x2 1 104110 Pleated 16x20x2 1 104110

Bearings - Bearings with a grease tting should be lubricated twice a year with a high

temperature, moisture-resistant grease. (Type NLGI-1 or -2 standard grease is recom-

mended.) Be sure to clean the grease tting before adding grease. Add grease with a

handgun until a slight bead of grease forms at the seal. Be careful not to unseat the seal by over lubricating. NOTE: If unusual environmental conditions exist (temperatures below 32°F or above 200°F; moisture; or contaminants), more frequent lubrication is required.

Setscrews - Check all of the setscrews (bearing/blower hubs and pulleys). Torque pulley setscrews a minimum of 110 in-lb to 130 in-lb maximum.

A bearing hub setscrew for a 1-3/8" to 1-3/4" shaft requires a 5/16" socket and a tightening torque of 165 in-lbs.

Belts - Check belt for proper tension and wear. If needed, follow instructions to adjust belt tension. Replace worn belts.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 7

Page 8

2-1/2” (63.5mm)

Fan and Motor Assembly showing Fan Blade Position

Cross-section of Installed Fan and Motor Assembly showing Cabinet Top

1.76” (44.7mm)

Top of Fan Blade

to Top of the

Cabinet Top Panel

Fan rotation is clockwise.

3.0 Maintenance and Service Procedures (cont'd)

3.2 Drive Components Cont'd)

Belts (cont'd) - Blower systems are equipped with either Power Twist Plus

blower belt or a solid belt. The linked belts are designed in sections allowing for easy sizing and adjustment. The belt is sized at the factory for the proper tension. If the belt needs adjustment, the recommended method of shortening the belt length is to count the number of links and remove one link for every 24. (A link is made up of two joining sections of belt. For easier removal of links, turn the belt inside out. But be sure to turn it back before installing.)

If equipped with a solid belt, adjust the belt tension by turning the adjusting screw on the motor base until the belt can be depressed 1/2" (13mm) on each side. After correct tension is achieved, re-tighten the locknut on the adjustment screw.

Proper belt tension is important to the long life of the belt and motor. Be sure belts are aligned in the pulleys. If a belt is removed or replaced, be sure the

directional arrows on the belt match the drive rotation. Motor and Blower - Inspect the motor mounts periodically. Remove dust and dirt accu-

mulation from the motor and wheel. The blower has cast iron, pillowblock, sealed bearings. Under most operating condi-

tions, re-lubrication is unnecessary. If lubrication is required, use a lubricant compatible to Shell Alvania #2 (lithium base - Grade 2). Operating temperature range is -30 to 230°F.

If any drive parts need to be replaced, use only factory-authorized replacements designed for the application.

linked

3.3 Condenser Fans

FIGURE 3 - Condenser Fan Assembly Dimensions and Rotation

3.4 Coil Maintenance

Condenser Coil Cleaning Instructions:

Form O-MAPSIII&IV Cabinets A/B/C, Page 8

Depending on the size, there are two, three, or four fans in the condenser section. If parts need to be replaced, use only factory authorized replacement parts. See FIGURE 3 for assembled dimensions and proper fan rotation.

The MAPS® cooling system is equipped with space-saving MACROCHANNEL Inspect all cooling system coils at the beginning of the cooling season or more often if needed. Follow the cleaning instructions below. If additional cleaning is required or if a coil must be removed for any reason, consult the factory. Be prepared to provide rating

plate and specic installation information.

Condensing Coil Access - The condensing coils are visible on the side of the unit (below the condenser fans). For additional access for inspection and maintenance, remove the tubing access panel (See FIGURE 1, page 5.).

1. Verify that the electrical power has been turned off and the disconnect switch locked.

2. Use a soft brush to remove any dirt and debris from the coils.

3. Spray with cold or warm (not hot) water and a cleaning solution (non-acid based coil

4. When clean, rinse with cool, clean water.

Evaporator Coil Access - The evaporative coils can be accessed by opening the coil cabinet door.

Inspect coils for debris, dirt, grease, lint, pollen, mold, or any element which would

obstruct heat transfer or airow. Inspect coils and tubing for physical damage. Inspect

coils.

cleaner is recommended). Due to possible damage to the coil, DO NOT use high pressure spray.

Page 9

feeders, piping connections, coil headers, and return bends for signs of fatigue, rubbing, and physical damage.

Clean the coils annually, or more often if needed. Use the proper tools and follow the instructions carefully to avoid damaging the coil. Use of a non-acid based coil cleaner is recommended. Due to possible damage to the coil, DO NOT use high pressure spray.

Evaporator Coil Cleaning Instructions:

3.5 Check Refrigerant Pressure and Temperatures (subcooling and superheat)

1. Verify that the electrical power has been turned off and the disconnect switch locked.

2. Open the access panels.

3. Use a soft brush to remove any dirt and debris from both sides of a coil.

4. Spray with cold or warm (not hot) water and a cleaning solution (non-acid based coil cleaner is recommended). Due to possible damage to the coil, DO NOT use

high pressure spray. First spray the leaving airow side, then the inlet airow side.

As much as possible, spray the solution perpendicular to the face of the coil. Follow the instructions on the cleaning solution. When cleaning process is

complete, rinse both sides with cool, clean water.

DANGER

These refrigeration circuits are high pressure systems. Hazards exist that could result in personal injury or death. Removal, installation, and service of this scroll compressor

must be performed by a technician qualied in R-410A

refrigerant. DO NOT USE service equipment or tools designed for R22 refrigerant. See Hazard Levels, page 3.

Two important requirements before checking superheat and subcooling:

1) This unit has fully intertwined refrigerant circuits and each circuit MUST be isolated before measuring its

temperature. Another active circuit will inuence the reading and make it impossible to determine accurate superheat

and subcooling.

2) If the circuit is equipped with an optional hot gas bypass valve, the valve must be disabled before measuring superheat and subcooling. Method of disabling depends on the model and date of manufacture.

MAPS®III Models without a shutoff valve in the line between the compressor discharge and the hot gas bypass valve

- Disable the hot gas bypass valve by removing the cover and adjusting the spring tension counterclockwise until the spring tension is relieved. Count and record the number of turns required so that you can return the bypass valve to its original setting. To check setting, refer to Paragraph 3.9.5.

Check SUBCOOLING

Measure and record temperature and pressure of the liquid line at the condenser coil outlet.

STEP 1) Record Measurements: Temperature = ________°F (°C) and Pressure = ________ psig

STEP 2) From Temperature/Pressure Conversion Chart (page 10), convert Measured Pressure (STEP 1) to

________°F (°C)

STEP 3) Subtract Measured Temperature (STEP 1) from Temperature from Conversion Chart (STEP 2)

________°F (°C) - ________°F (°C) = ________°F (°C) degrees of Subcooling

Recommended subcooling with outdoor temperature range of 70 to 95°F (21 to 35°C)

is 10 to 12 degrees F (5.6 to 6.7 degrees C).

Too much subcooling indicates a refrigerant overcharge. To reduce the subcooling, remove excess refriger-

ant. Too little subcooling indicates a refrigerant undercharge. To increase subcooling, slowly add R-410A refrigerant.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 9

Page 10

3.0 Maintenance and Service Procedures (cont'd)

3.5 Check Refrigerant Pressure and Temperatures (cont'd)

WARNING

Do not release refrigerant to the atmosphere. When adding or

removing refrigerant, the qualied technician must comply

with all national, state/province, and local laws.

Determine SUPERHEAT

Measure and record temperature (insulate probe from surrounding air temperature) and pressure in the suction line at the compressor inlet.

STEP 1) Record Measurements: Temperature = _______°F (°C) and

Pressure = _______ psig

STEP 2) From Temperature/Pressure Conversion Chart (below), convert

Measured Pressure (STEP 1) to ________°F (°C)

STEP 3) Subtract Measured Temperature (STEP 1) from Temperature from

Conversion Table (STEP 2)

________°F (°C) - ________°F (°C) = ________°F (°C) degrees of

Superheat

Recommended superheat range is 8 to 12 degrees F (4.5 to 6.7 degrees C).

Typically, too much superheat indicates that the evaporator coil is undercharged. Too little superheat typically indicates that the evaporator coil is overcharged and

may potentially ood liquid refrigerant to the compressor. To reduce the superheat,

adjust the thermal expansion valve by turning the adjusting stem counterclockwise. To increase the superheat, adjust the thermal expansion valve by turning the adjusting stem clockwise.

Temperature/Pressure Conversion Chart

R-410A Refrigerant R-410A Refrigerant R-410A Refrigerant R-410A Refrigerant R-410A Refrigerant

Pressure Temperature Pressure Temperature Pressure Temperature Pressure Temperature Pressure Temperature

PSI °F °C PSI °F °C PSI °F °C PSI °F °C PSI °F °C

1.8 -55 -48.3 49.5 1 -17.2 77.0 19 -7.2 112.2 37 2.8 218.2 75 23.9

4.3 -50 -45.6 50.9 2 -16.7 78.7 20 -6.7 114.4 38 3.3 235.9 80 26.7

7.0 -45 -42.8 52.2 3 -16.1 80.5 21 -6.1 116.7 39 3.9 254.6 85 29.4

10.1 -40 -40.0 53.6 4 -15.6 82.3 22 -5.6 118.9 40 4.4 274.3 90 32.2

13.5 -35 -37.2 55.0 5 -15.0 84.1 23 -5.0 121.2 41 5.0 295.0 95 35.0

17.2 -30 -34.4 56.4 6 -14.4 85.9 24 -4.4 123.6 42 5.6 316.9 100 37.8

21.4 -25 -31.7 57.9 7 -13.9 87.8 25 -3.9 125.9 43 6.1 339.9 105 40.6

25.9 -20 -28.9 59.3 8 -13.3 89.7 26 -3.3 128.3 44 6.7 364.1 11 0 43.3

27.8 -18 -27.8 60.8 9 -12.8 91.6 27 -2.8 130.7 45 7.2 389.6 11 5 46.1

29.7 -16 -26.7 62.3 10 -12.2 93.5 28 -2.2 133.2 46 7.8 416.4 120 48.9

31.8 -14 -25.6 63.9 11 -11.7 95.5 29 -1.7 135.6 47 8.3 444.5 125 51.7

33.9 -12 -24.4 65.4 12 -11.1 97.5 30 -1.1 138.2 48 8.9 474.0 130 54.4

36.1 -10 -23.3 67.0 13 -10.6 99.5 31 -0.6 140.7 49 9.4 505.0 135 57.2

38.4 -8 -22.2 68.6 14 -10.0 101.6 32 0.0 143.3 50 10.0 537.6 140 60.0

40.7 -6 -21.1 70.2 15 -9.4 103.6 33 0.6 156.6 55 12.8 571.7 145 62.8

43.1 -4 -20.0 71.9 16 -8.9 105.7 34 1.1 170.7 60 15.6 607.6 150 65.6

45.6 -2 -18.9 73.5 17 -8.3 107.9 35 1.7 185.7 65 18.3 645.2 155 68.3

48.2 0 -17.8 75.2 18 -7.8 110.0 36 2.2 201.5 70 21.1

Form O-MAPSIII&IV Cabinets A/B/C, Page 10

Page 11

3.6 Compressor

Compressor B

Compressor C

Compressor A

Compressor

Dh (Reheat)

Operation, Maintenance, and Replacement

DANGER

The refrigeration circuits are high pressure systems. Hazards exist that could result in personal injury or death. It is therefore required that the removal and installation of this

scroll compressor be performed by a technician qualied in

R-410A refrigerant. See Hazard Levels, page 3.

DANGER

Never use oxygen to pressurize a refrigeration system. Oxygen can explode on contact with oil and could result in personal injury or death. When using high pressure gas such as nitrogen for this purpose, ALWAYS USE A PRESSURE REGULATOR that can control the pressure down to 1 or 2 psig. Failure to use a regulator will result in extremely high pressure which could exceed the burst pressure of the compressor or other system components and result in personal injury or death. See Hazard Levels, page 3.

WARNINGS

For your safety, wear eye protection, gloves, and protective clothing when handling refrigerant and oil and when brazing.

Have a re extinguisher nearby. See Hazard Levels, page 3.

Compressor Staging (Cooling) - applies to all MAPS®III Models

Each MAPS®III system leaves the factory with the compressor staging sequence shown here for that Model and Size. The compressor will start based upon a call for cooling to maintain the discharge air temperature setpoint. There is a minimum 240 second ON and OFF time for each stage (not compressor).

FIGURE 4 - Identication of

Compressors by Circuit and Staging for MAPS®III Models

Cabinet

Size

A or B

Cooling

Size

(RCB)

060 078 090

118

136

160 184 B A A+B A+B+C --

186

200

190

216

298

410

Cooling/

Reheat Size

(RDB)

084 B A A+B -- -102 B A A+B -- -114 B A A+B -- -142 B A A+B -- -162 B A A+B -- --

210 A B A+C A+B A+B+C 222 A B A+C A+B A+B+C 224 A B A+B B+C A+B+C 236 A B A+B B+C A+B+C 248 A B A+B -- -262 A B A+B -- -272 B B+C A+B+C -- -288 B B+C A+B+C -- -354 B A+B B+C A+B+C -370 B A+B B+C A+B+C -468 B A+B A+B+C -- -482 B A+B A+B+C -- --

Cooling Staging by Compressor

Circuit

1st 2nd 3rd 4th 5th

Compressor

NOTE: Staging listed by cooling only Models RCB/RDB also

applies to Models RDCB /RDDB with gas heat and Models RECB/ REDB with electric heat.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 11

Page 12

3.0 Maintenance/Service Procedures (cont'd)

Alarm Light (Red LED) - See Paragraph 7.2.

Compressor Modualting Solenoid Valve Energized Light (Yellow LED)

Power Light (Green LED)

3.6 Compressor Operation, Maintenance, and Replacement (cont'd)

Compressors and Crankcase Heater P/N's by Voltage on MAPS®III Models

208-240/3/60 480/3/60 575/3/60

Compressor

Model P/N Model P/N Model P/N

ZP24K5E 235095 216434 ZP24K5E 235097 216436 ZP24K5E 235099 216437 ZP36K5E 235096 216398 ZP36K5E 235098 216400 ZP36K5E 235100 216401 ZP54K5E 235008 216398 ZP54K5E 235012 216400 ZP54K5E 235016 216401 ZP57K3E 216686 216398 ZP57K3E 216687 216400 ZP57K3E 216688 216401 ZP72KCE 235009 216398 ZP72KCE 235013 216400 ZP72KCE 235018 216401 ZP83KCE 216689 216398 ZP83KCE 216690 216400 ZP83KCE 216691 216401 ZP137KCE 235010 216398 ZP137KCE 235014 216404 ZP137KCE 235019 216405 ZPT144KCE 235011 216398 ZPT144KCE 235015 216400 ZPT144KCE 235020 216401 ZP154KCE 220260 216402 ZP154KCE 220261 216404 ZP154KCE 220262 216405

Crankcase Heater P/N

Compressor

Crankcase Heater P/N

Compressor

Crankcase Heater P/N

Modulating Cooling -

MAPS

IV Models

MAPS®IV units are equipped with a modulating capacity compressor and a digital con-

troller to provide cooling modulation. The digital controller in the control compartment (See FIGURE 1, page 5) is the electronic interface between the compressor and the

NOTE: To identify MAPS®IV Models, see Paragraph 1.0.

system controller. The compressor controller is connected to the unit controller to provide protection and diagnostics for modulating compressor operation.

After a compressor shutdown, a two-minute anti-short cycle timer in the compressor

controller delays the compressor restart. The unit controller has a ve-minute compressor on/off time. The delay times are concurrent so total delay time is ve minutes.

FIGURE 5 - Compressor Digital Controller located in the control compartment interfaces the modulating capacity compressor with the unit controller.

LED Color

Green Solid

Green Flashing Anti-short cycle timer is active

Yellow Solid

Red Not lit No abnormal operation alerts

NOTE: See Troubleshooting, Paragraph 7.2.

LED State

Indicates

Power (24VAC present at power terminals)

Unloader (Solenoid valve is

energized; compressor capacity is 0.)

Compressor and Crankcase Heater P/N's by Voltage on MAPS®IV Models

208-240/3/60 480/3/60 575/3/60

Compressor

Model P/N Model P/N Model P/N

ZP24K5E 235095 216434 ZP24K5E 235097 216436 ZP24K5E 235099 216437 ZP36K5E 235096 216394 ZP36K5E 235098 216396 ZP36K5E 235100 216397 ZP54K5E 235008 216394 ZP54K5E 235012 216396 ZP54K5E 235016 216397 ZP57K3E 216686 216398 ZP57K3E 216687 216400 ZP57K3E 216688 216401 ZP61KCE 261235 216398 ZP61KCE 261236 216400 ZP72KCE 235018 216401 *ZPD61KCE 261145 216398 *ZPD61KCE 261146 216400 ZP83KCE 216691 216401 ZP72KCE 235009 216398 ZP72KCE 235013 216400 *ZPD83KCE 261149 216401 ZP83KCE 216689 216398 ZP83KCE 216690 216400 ZP137KCE 235019 216405 *ZPD83KCE 261147 216398 *ZPD83KCE 261148 216400 *ZPD137KCE 261155 216405 ZP137KCE 235010 216402 ZP137KCE 235014 216404 *ZPD61KCE 268531 216401 *ZPD137KCE 261153 216402 *ZPD137KCE 261154 216404 ZP61KCE 268532 216401 ZP154KCE 220260 216402 ZP154KCE 220261 216404 *ZPDT14MCE 268533 216401 *ZPDT14MCE 262656 (2)216398 *ZPDT14MCE 262657 (2)216400 * Modulating capacity compressor

Form O-MAPSIII&IV Cabinets A/B/C, Page 12

Crankcase Heater P/N

Compressor

Crankcase Heater P/N

Compressor

Crankcase Heater P/N

Page 13

Compressor Replacement

WARNINGS

For your safety, wear eye protection, gloves, and protective clothing

when handling refrigerant and oil and when brazing. Have a re

extinguisher nearby. See Hazard Levels, page 2.

Compressor Handling

Do not lift compressor by copper tubing. To prevent internal damage, compressors

must ALWAYS be held upright.

The following instructions include major points of consideration that will ensure proper installation and protect you from potential personal injury. Please use the following 13 steps as a checklist, taking each item in order before proceeding to the next. If more information is required, contact the Reznor HVAC Service Department for Reznor products.

WARNING

To avoid electrical shock, power to the compressor(s) MUST REMAIN OFF during performance of Steps 1 through 9 below. LOCK DISCONNECT SWITCH OFF (open).

□ Step 1. Verify Proper Application

Verify that the replacement compressor is identical to the model being replaced. All system components are matched to the compressor. Replacing a compressor with a model other than the Reznor® specied replacement will void the product warranty. See part numbers for R-410A compressors in the tables on page 12.

□ Step 2. Determine Cause of Initial Failure and Remove the Compressor

In order to prevent a second failure, the cause of the original failure must be determined. Identify the cause and make the necessary repairs.

CAUTION: DO NOT LIFT compressor by copper tubing; damage will occur. Compressor must remain upright.

WARNING

Wear eye protection and gloves when handling refrigerant or oil and when brazing.

a) BEFORE REMOVING THE FAULTY COMPRESSOR, remove refrigerant

charge using proper recovery procedures. Call 1-800-441-9450 for the name of the nearest Dupont authorized distributor or 1-800-ASK-KLEA (IGI) for information on their refrigerant reclaim programs.

b) Disconnect wires. All compressor wiring is connected using a black molded

plastic plug. Remove the plug from the compressor.

c) Open access ports so that pressure does not build up in the system. Before

unbrazing stubs from the compressor, cut suction and discharge tubing with a tubing cutter.

WARNING

Have a re extinguisher near. The compressor contains oil. There is a risk of re when unbrazing stubs.

Use a high temperature torch to disconnect the suction line and the discharge line from the compressor.

d) Remove the mounting bolts and the compressor. Save the mounting hardware

to attach the grommets and sleeves shipped with the replacement compressor.

e) To test for acid and to assure excess oil does not remain in the circuit, remove

oil from the failed compressor. Measure the amount of oil.

CAUTION: In addition to the required eye protection and gloves, care should be taken in handling POE oil because it may cause damage to

certain plastics and roong materials. See Hazard Levels, page 3.

If the oil taken from the compressor and measured is found to be signicantly

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 13

Page 14

3.0 Maintenance/ Service Procedures (cont'd)

3.6 Compressor

Maintenance (cont'd)

lower than listed in the table on page 14, clean the excess oil through use

of suction and liquid line lter driers. Beginning in Step 4, follow the same

procedure as for burnout cleanup.

Use an acid test kit to check the oil for acid. If acid is found, beginning in Step

Compressor Oil Charge (POE Oil)

Compressor Model cc oz

ZP24K5E 621 21

ZP36K5E 1124 38

ZP54KCE 1242 42

ZP57K3E 1715 58

ZP61KCE 1538 52

ZPD61KCE 1774 60

ZP72KCE 1774 60

ZP83KCE 1656 56

ZPD83KCE 1656 56

ZP137KCE 3253 110

ZPD137KCE 3135 106

ZPT144KCE 3312 112

ZP154KCE 3253 110

ZPDT14MCE 3135 106

4, follow procedures indicated for burnout cleanup. Dispose of oil and compressor using an approved environmentally safe

disposal method.

Important NOTES: These R-410A compressors use a polyolester (POE) lubricant. Types of recommended POE

oil are Copeland Ultra 22 CC, Copeland Ultra 32 CC, Copeland Ultra 32-3MAF, Mobil EAL, Arctic 22 CC, Uniqema Emkarate RL32CF, or Uniqema RL32-3MAF.

POE oil absorbs moisture much quicker and to a greater degree than standard mineral oil. The compressor must not be left open longer than 15 minutes during replacement. During installation the system must be swept with an inert gas such as dry nitrogen to keep moisture from entering the compressor and prevent the formation of oxides.

• Step 3. Mount the Replacement Compressor

• Step 4. Install New Filter Driers (Select procedure that applies.)

Form O-MAPSIII&IV Cabinets A/B/C, Page 14

Do not remove the dust cover or rubber shipping plugs until all other system

connections are complete (i.e. new liquid line lter drier(s) installed and all tubing

changes made - see Steps 4 and 5). The amount of time the compressor is open to the atmosphere must be kept to a minimum.

Use the new mounting grommets and sleeves that are shipped with the compressor to mount it. The sleeves will prevent over compression of the grommets. Re-use the mounting bolts from the compressor that was removed. The mounting bolts will bottom out when tight.

IF the oil measured in Step 2 was not signicantly less than the amount shown in the table above or the test for acid in Step 2 did NOT indicate burnout , install

a new R-410A refrigerant liquid line lter drier. The lter drier must be rated for

no less than 600 psig and be the proper size for the circuit. Because R-410A refrigerant requires POE oil which absorbs moisture quickly, it is important to

change the lter drier any time the circuit is opened. It is recommended to use a tubing cutter when cutting out a lter drier as the

desiccant absorbs and holds moisture better when it is cool. Heat from a torch

may cause moisture to leave the lter and be absorbed in the oil. Be careful to keep dirt, lings, and other contaminants out of the system.

Continue to Step 5. IF the oil measured in Step 2 was signicantly less than shown in the table above

or the test for acid in Step 2 did indicate compressor burnout, do the following:

a) Install a liquid line lter drier. If there is acid, install an acid removing lter

drier. Size the acid-removing lter drier at least one capacity size larger than

normally required for the circuit.

b) Install a temporary lter drier in the suction line. When there is acid, a 100%

activated alumina suction lter drier is recommended. The suction line drier should be sized properly for the circuit and have a service access tting to monitor pressure drop across the drier. (NOTE: Suction line lter drier must be

removed after 72 hours of operation.)

Page 15

Step 12 includes the remaining procedures required for cleanup of a burnout. Continue to Step 5.

• Step 5. Braze on Suction and Discharge Lines

CAUTION: Do not leave system open to the atmosphere any longer than minimum required for installation. POE oil in the compressors is extremely susceptible to moisture absorption. Always keep ends of tubing sealed during installation. See Hazard Levels, page 3.

Brazing materials must be able to withstand the high pressure of R-410A

refrigerant. A high temperature, silver phosphate type brazing with 5% or greater

alloy is recommended. To prevent oxidation, purge tubing with 2-3 psig of regulated dry nitrogen while it

is being brazed. Open the service valve as needed to release the nitrogen. Do not allow moisture to enter the system.

The installer is responsible for brazing and for complying with appropriate standard refrigerant piping procedures.

CAUTION: All brazing should be done using a 2-3 psig dry nitrogen

purge owing through the pipe being brazed.

CAUTION: When brazing, protect all painted surfaces and components from excessive heat. Wet wrap all valves but do not allow moisture to enter the tubing. See Hazard Levels, page 3.

• Step 6. Check System for Leaks

After installation is complete, pressurize the circuit with helium or dry nitrogen to approximately 150 psi (maximum pressure is 450 psi). Check for leaks using soap bubbles or other leak-detecting methods.

• Step 7. Evacuate the Circuit

Evacuate one circuit at a time. Use a vacuum pump and micron gauge. Each circuit must be evacuated to hold a 500 micron vacuum. Vacuum must be pulled

on both the discharge (high) and suction (low) side. Do the suction side rst; and

the compressor discharge side second. To establish that a circuit is leak-free and moisture-free, a standing vacuum test is recommended. Close off the valve to the vacuum pump and observe the micron gauge. If the vacuum gauge does not rise above 500 microns in one minute, the evacuation should be complete. If the vacuum gauge does rise above 500 microns in one minute, evacuation is incomplete or the circuit has a leak. Repeat as needed until evacuation is complete. The evacuation process must be done on each circuit.

NOTE: Evacuation will not remove moisture from POE oil. Moisture must be prevented from getting in the oil.

Continue and/or repeat Steps 6 and 7 until evacuation is complete.

CAUTION: Do not use the replacement compressor as an evacuation assist and never apply voltage to a compressor while it is in a vacuum. See Hazard Levels, page 3.

Moisture and air are harmful to the system because they increase the condensing temperature, raise the discharge gas temperature, cause formation of acids, and cause oil breakdown.

CAUTION: Do not leave a circuit open to the atmosphere any longer than minimum required for installation. POE oil in the compressor is extremely susceptible to moisture absorption. Evacuation will not remove moisture from POE oil.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 15

Page 16

Compressor B

Compressor C

Compressor A

Compressor

Dh (Reheat)

3.0 Maintenance/ Service Procedures (cont'd)

3.6 Compressor Maintenance (cont'd)

CAUTION: Crankcase heaters must be allowed to warm up for at least 24 hours prior to startup. Disable cooling controls before turning on power to warm up crankcase heaters.

• Step 8. Check the Electrical System

After the system has been evacuated, reconnect the electrical plug to the compressor or the wires to the compressor terminals. It is a normal practice to replace all starting components any time a compressor is changed.

WARNING

Do not apply voltage to the compressor when the plug is removed or terminals disconnected.

Crankcase Heater - Connect the crankcase heater. The crankcase heater is energized continuously and is extremely important to proper compressor operation and long life. NOTE: See crankcase heater P/N's on page 12.

The crankcase heater must be energized for at least 24 hours before starting the unit or after a power outage of more than 8 hours. Be sure to disable cooling controls before turning on power to warm up crankcase heaters.

• Step 9. Charge the System (Use R-410A refrigerant only.)

Refer to the applicable table (either MAPS®III or MAPS®IV) for the approximate amount of refrigerant required. Follow the instructions below to charge the circuit. R-410A refrigerant MUST BE charged as a LIQUID.

NOTE: Outdoor temperature must be between 70-95°F (21-35°C) for verifying superheat and subcooling. If temperature is not within this range, consult the factory service department before charging.

If equipped with an optional hot gas bypass, disable the hot gas bypass valve before charging. Method of disabling depends on the model and date of manufacture.

All MAPS®IV Models & any MAPS®III Models with a shutoff valve in the line between the compressor discharge and the hot gas bypass valve - Locate the shutoff valve. Disable the hot gas bypass valve by closing the shutoff valve. When measurements are complete, be sure to open the valve. MAPS®III Models without a shutoff valve in the line between the compressor discharge and the hot gas bypass valve - Disable the hot gas bypass valve by removing the cover and adjusting the spring tension counterclockwise until the spring tension is relieved. Count and record the number of turns required so that you can return the bypass valve to its original setting. To check setting, refer to Paragraph 3.9.5.

Liquid charge the high side to 80%. With the system running, add the balance of

the charge to the correct superheat and subcooling values. Refer to Step 11, page 17, and the instructions in Paragraph 3.5, page 9.

IMPORTANT: Do not release refrigerant to the atmosphere! If required service

procedures include the adding or removing of refrigerant, the qualied HVAC service

technician must comply with all federal, state or provincial, and local laws.

Approximate R410-A Refrigerant Charge (lbs) for MAPS®IV Models by Size and Compressor for Each Circuit

Form O-MAPSIII&IV Cabinets A/B/C, Page 16

Cabinet

A 060 084 N/A 8.0 N/A 4.2

A or B

RCC/

RDCC/

RECC

090 114 N/A 10.5 N/A 4.2 120 144 8.0 8.0 N/A 4.2

160

200

190

298

410

RDC/

RDDC/

REDC

R410-A Charge (lbs) by Compressor Circuit

A B C

184

196 4.2 236

257 6.0

248

262 10.0 354 370 10.0

468

482 10.0

9.5 9.5 N/A

5.5 6.0 5.5

9.0 10.5 N/A

11.0 11.0

10.5 10.5 10.5

(Reheat)

4.2

6.0

10.0

Page 17

Approximate R410-A Refrigerant

Compressor B

Compressor C

Compressor A

Compressor

Dh (Reheat)

Charge (lbs) for MAPS

III Models by Size and Compressor for Each Circuit

• Step 10. System Startup

Assure voltage to compressor does not drop below minimum allowable voltage (e.g. 187 volts for 230/208-3-60, 415 volts for 460/3/60, 518 volts for 575/3/60) during the period the compressor is trying to start. If a low voltage or voltage

imbalance condition exists, the electrical problem must be determined and corrected prior to operating the unit.

Voltage Imbalance - Voltage imbalance is becoming a more common problem.

In a 3-phase system, excessive voltage imbalance between phases will cause motors to overheat and compressors to fail. Maximum allowable imbalance is

2%. To determine voltage imbalance, measure and record the voltage of all three

phases. Take the measurements at the compressor terminals with the compressor operating.

Voltage Imbalance Formula:

Key:

Formula:

If the imbalance is within the 2% tolerance, voltage imbalance is not a problem and the system may be operated. If the imbalance exceeds the 2% tolerance, follow

the procedures below.

Solutions to Voltage Imbalance:

The cause for a voltage imbalance problem can originate at the power company or can be caused inside the building. Try the following on-site solution to determine if the problem can be easily resolved.

Roll the connections at the compressor terminals one forward. Connect the wire now on Terminal 1 to Terminal 2, 2 to 3, and 3 to 1. Re-measure and re-calculate

the voltage imbalance. If the imbalance is within 2%, the system may be operated.

If the imbalance is not within tolerance, roll the connections one more forward. Re-measure and re-calculate the voltage imbalance. If the imbalance is within

2%, the system may be operated. If the voltage imbalance still exceeds 2%, do

not start the system. Contact the building owner or person responsible to have an electrician analyze the buildings's power supply and load distribution.

Power Supply Voltage Phasing - Connect refrigerant pressure gauges to the suction and discharge lines of the compressors and an electric meter to the power supply.

Cabinet

A 060 084 4.3 4.0 N/A 4.2

A or B

RCB/

RDCB/

RECB

078 102 5.2 4.0 N/A 4.2 090 11 4 5.7 4.8 N/A 4.2

118 142 6.5 4.8 N/A 4.2 136 162 6.5 5.7 N/A 4.2 160 184 6.5 4.8 4.2 4.2

186

200

190

216

298

410

RDB/

RDDB/

REDB

210 222 6.0 224 236 6.0 248 262 10.0 272 288 10.0 354 370 10.0 468 482 10.0

R410-A Charge (lbs) by Compressor Circuit

A B C DH (Reheat)

5.2 6.0 5.2

5.2 6.0 6.0

8.0 10.5 N/A

11.0 8.5

11.0 11.0

10.5 10.5 10.5

4.2

9.5

V1, V2, V3 = line voltages as measured

VA (Average )= (V1 + V2+ V3) / 3

VD = Line Voltage (V1, V2, or V3 that deviates farthest from average (VA)

% of Voltage Imbalance = [100 (VA - VD)] / VA

CAUTION: Be sure to connect pressure gauges to the suction and discharge lines before system startup so that compressor rotation can be checked immediately. Scroll compressors will be destroyed if allowed to operate in the wrong direction. See Hazard Levels, page 3.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 17

Page 18

3.0 Maintenance/ Service Procedures (cont'd)

3.6 Compressor

Maintenance (cont'd)

• Step 10. System

Startup (cont'd)

NOTE: To identify MAPS

and MAPS®IV Models, see Paragraph 1.0.

IMPORTANT: Do not

release refrigerant to the atmosphere!

If required service procedures include the adding or removing of refrigerant, the

qualied HVAC

service technician must comply with all federal, state or provincial, and local laws.

Record the ambient temperature. Adjust the system controller so that a call for cooling exists.

NOTE: Outdoor ambient lockouts may prevent mechanical cooling. Temporarily override lockouts by lowering the cooling setpoint. When testing is complete, reset the controller.

Because it is possible to unknowingly connect 3-phase power in such a way as to cause the scroll compressor or blower to rotate in reverse, it is very important to check this on startup.

Check Compressors - Immediately at startup, observe the gauges. If the suction pressure rises and discharge pressure drops, the compressor is operating in reverse and must be shut down. Turn off the power and switch the 3-phase line voltage wiring connections before restarting the unit.

Important: If allowed to operate for several minutes in reverse, the compressor’s

internal protector will trip. If a compressor is repeatedly allowed to restart and run in reverse, the compressor will be permanently damaged.

• Step 11. Check Subcooling and Superheat

Superheat is the verication that the evaporator coil is properly using the

refrigerant supplied. Too much superheat indicates that the coil is undercharged.

Too little superheat indicates that the coil is overcharged and potentially ooding

liquid refrigerant to the compressor. Subcooling is the measurement of liquid refrigerant stored in the condenser

coil. Too much subcooling indicates a system overcharge. Too little subcooling indicates a system undercharge and may not provide the thermal expansion valve with a full column of liquid refrigerant for proper operation.

Two important requirements before checking superheat and subcooling:

1) This unit has fully intertwined refrigerant circuits and each circuit MUST be

isolated before measuring its temperature. Another active circuit will inuence the

reading and make it impossible to determine accurate superheat and subcooling.

III

Follow the procedures in Paragraph 3.5 to check subcooling and superheat.

• Step 12. (Select the procedure that applies.)

IF the oil measured in Step 2 was signicantly less than in the table on

page 14 or the acid test in Step 2 indicated a burnout, do the following:

a) Operate the unit for several hours. Check the pressure drop through the

temporary suction line lter drier. If the pressure drop exceeds 8 psig, recover the refrigerant, replace the suction line lter drier with the same type as removed, replace the liquid line lter drier, evacuate the circuit, and re-charge

with the recovered refrigerant.

Continue to monitor the pressure drop through the suction line lter drier and

repeat the process above until the pressure does not exceed 8 psig after several hours of operation. (NOTE: System must be allowed to run no more

than 72 hours with a suction line lter drier.)

b) Allow the system to operate for 4-8 hours. Recover the refrigerant and take an

oil sample. Retest the oil for acid.

Form O-MAPSIII&IV Cabinets A/B/C, Page 18

Page 19

c) If the test for acid is negative, remove the suction line lter drier, replace

Compressor B

Compressor C

Compressor A

Compressor

Dh (Reheat)

the liquid line drier, evacuate, and re-charge the system with the recovered refrigerant. If the test indicates acid, replace both the liquid line lter drier and the suction

line lter drier and repeat b) and c).

CAUTION: After cleanup is complete, remove the suction line lter

drier. See Hazard Levels, page 3.

d) Verify subcooling and superheat (refer to Step 11). e) When the system is operating properly, remove the gauges.

Or, IF the oil measured in Step 2 was not signicantly less than that shown in the table on page 14 or the acid test in Step 2 did not indicate a compressor burnout, continue to the review in Step 13.

• Step 13 . Review ALL Steps to ensure that nothing was overlooked.

3.7 Thermostatic Expansion Valves

All refrigeration circuits have a thermostatic expansion valve. Thermostatic expansion valves do not have replaceable parts. If a replacement valve is required, it must be for R410-A refrigerant and must be sized correctly for the application. All refrigerant

service should be performed by a service technician qualied in R410-A refrigerant.

Replacement valve P/N's by Model, size, and circuit are listed in the following tables.

FIGURE 6 - Thermostatic Expansion Valve

Cabinet

Size

A or B

Cabinet

Size

A or B

RCB/

RDCB/

RECB

A 060 084 220553 220552 -- 220552

078 102 220554 220552 -- 220552

090 114 220554 220553 -- 220552

118 142 220555 220553 -- 220552

136 162 220555 220554 -- 220552

160 184 220555 220554 220552 220552

186

200

190

216

298

410

RCC/

RDCC/

RECC

RDB/

RDDB/

REDB

210

222 220553

224

236 220553

248

262

272

288

354

370

468

482

RDC/

RDDC/

REDC

060 090 120 144 220554 220554 N/A 220552

160

200

190

298

410

084 N/A 220554 N/A 220552 114 N/A 220555 N/A 220552

184 196 220553 236 257 234967 248 262 234987 354 370 234987 468 482 234987

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 19

Thermostatic Expansion Valve P/N's by

Compressor Circuit

A B C DH (Reheat)

220554 220555 220554

220554 220555 220555

234987 220558 N/A

220558 220555

220558 220558

220558 220558 220558

Thermostatic Expansion Valve P/N's

by Compressor Circuit

A B C DH (Reheat)

220555 220555 N/A

220554 220556 220554

234967 261175 N/A

261175 261175

261175 261175 261175

220552

234987 234987

220552

220553

234987

Page 20

3.0 Maintenance/ Service Procedures (cont'd)

FIGURE 7 - Damper Motor

3.8 Optional Dampers and Damper Controls

Inlet Air Dampers

Location: Dampers and damper motors are located in the inlet air opening. Function: Dampers operate in response to a variety of controls (GF Options). Service: Clean dampers and controls of dust and dirt.

2-Position Damper Motor (Options AR8, AR2D, AR2L)

Function: The 2-position damper motor opens and closes the dampers in response to

unit operation or a eld-supplied time clock. The motor closes the dampers on heater shutdown.

Modulating Motor (Options AR25, AR2G, AR2H, AR2K)

Function: The modulating damper motor actuates the dampers in response to the

selected control with actuation from input switch settings. The motor closes the inlet dampers on heater shutdown.

Service: Other than external cleaning, there is no service required on the dampers or the damper motor. If the damper, control, or motor need to be replaced, replace with a factory-authorized replacement. For additional information on damper controls (Options GF 1-9), see the system installation manual Form I-MAPSIII&IV.

3.9 Other Controls

FIGURE 8 - I/Q System Programmable Controller and Unit Module Interface with Display

Refer to Control Instruction Form CP-MAPS D15/16/17/18 for information on the programmable controller.

3.9.2 Air Proving Switch

3.9.1 Programmable Digital Controller and Sensors

All MAPS® systems have a unit-mounted,

BACview Display

I/Q System Controller

Some sensors are standard and others will depend on option selection. Service: If a sensor needs to be replaced, use only a factory authorized replacement

part designed for the purpose. Refer to the digital wiring requirements in Paragraph 7.4 of Installation Form I-MAPSIII&IV.

If a controller needs to be replaced, it must be replaced with the same controller and software.

Function: The airow proving switch is a pressure switch that veries

to the main controller that the blower is operating. Service: If the switch needs to be replaced, use a factory-authorized

replacement designed for the application.

24-volt I/Q programmable controller. Depending on how it was ordered, the system is equipped for either neutral air/ discharge air control (Option D15) or space control with discharge air reset (Option D16). In addition, MAPS®IV electric heat Model RECC for process applications may have neutral air/discharge air control (Option D17) or space control with discharge air reset (Option D18). The controller is factory programmed to match the selection. See the control instruction manual, Form CP-MAPS D15/16/17/18, for more details.

3.9.3 Motor Starter (Option AN10) or Variable Frequency Drive (Option VFD2)

Form O-MAPSIII&IV Cabinets A/B/C, Page 20

Function: When the main controller calls for blower operation, either an IEC type starter with a contactor or a variable frequency drive (VFD) module responds to operate the motor.

The starter is in the high voltage control compartment. The VFD was eld installed in

a location that is no more than 50 feet (15M) away where the minimum temperature is 18°F (-9°C). Control of the variable frequency drive module is coordinated with the main controller, and depending on what was ordered, can function in response to temperature, CO2, or pressure controls.

Service: If a starter or contactor need replaced, use only the identical replacements that are designed to match the motor and voltage of the system.

Page 21

If a VFD needs to be replaced, contact the factory service department. Be prepared to provide the model, serial, and wiring diagram number.

3.9.4 Voltage Protection, Option PL4

3.9.5 Hot Gas Bypass Valve (Option AUC9)

FIGURE 9 - Hot Gas Bypass Valve

3.9.6 Modulating Reheat (Option AUR1) - RDB, RDC, RDDB, RDDC, REDB, REDC

Function: Phase loss and low or high voltage can cause damage to electrical com-

ponents. This safety control monitors phase loss and voltage and shuts down the unit when its limits are exceeded. The device is auto reset and allows the unit to restart when the power conditions are corrected.

Function: The hot gas bypass valve allows some of the refrigerant gas from the suction line to be re-routed directly to the evaporator coil providing for expanded compressor modulation at low outside air temperatures.

Service: To check the hot gas bypass valve setting, connect a pressure gauge to the suction line and block the entering air to the evaporator coil. Suction pressure will drop, and the hot gas bypass valve should begin to open at a approximately 115 psi and will be fully open at 95 psi. When the valve begins to open it will be hot to the touch (see caution below).

CAUTION: Touching the operating hot gas bypass valve can cause a burn. Use caution when checking and adjusting the valve. See Hazard Levels, page 3.

If a hot gas bypass valve needs to be replaced, use only a factory-authorized replace-

ment for R410-A refrigerant. All refrigerant service should be done by a qualied R410-A

service technician.

Function: Units with modulating reheat control (Option AUR1) have a temperature control board with a potentiometer, an air temperature sensor, and an electric discharge bypass valve. When reheat is active, the sensor monitors the air temperature as it leaves the reheat coil. Based on the potentiometer setpoint, the board will open or close the bypass valve. If the leaving air temperature is higher than the setpoint, the board will open the valve adding refrigerant hot gas to the refrigerant liquid before it enters the pre-cool coil. This reduces the coil's ability to absorb the heat, and thus, the reheat coil's ability to reject. If the leaving air temperature is lower than the setpoint, the opposite occurs.

Service: Check the wiring connections at the board. The board is polarity sensitive;

positive connects to terminal 1 and negative to terminal 2. The valve may be tested by measuring the resistance of the leads. Remove the power

and the leads from the board before testing. Resistance between the black and white leads should be about 75 Ohms. Resistance between the green and red leads should

be within 5% of the white and black.

Use only factory-authorized replacement parts.

4.0 Gas Heat Section Maintenance Models RDCB, RDCC, RDDB, and RDDC

This gas heater will operate with a minimum of maintenance. To ensure long life and satisfactory performance, a heater that is operated under normal conditions should be inspected and cleaned at the start of each heating season. If the heater is operating in an area where an unusual amount of dust or soot or other impurities are present in the air, more frequent maintenance is recommended. When any service is completed, be careful to reassemble correctly to ensure that no unsafe conditions are created. When re-lighting, always follow the lighting instructions on the furnace.

WARNING

Turn off the power before performing maintenance procedures. Lock disconnect switch in OFF position. When you turn off the power supply, turn off the gas at the external manual valve. See Hazard Levels, page 2.

4.1 Heat Exchanger,

Burner, and Venter

This gas heat section is equipped with a Inspect the gas heat section annually to determine if cleaning is necessary. If there is an accumulation of dirt, dust, and/or lint, clean the compartment.

TCORE

style heat exchanger and burner.

Maintenance

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 21

Page 22

Venter Motor and Wheel Assembly

Venter Side Supports

Venter Housing and Support

Flue Collection Box Assembly

Venter Support

Venter

Housing

Venter

Housing

Gasket

Motor and

Wheel Assy

OR, depending on the Cabinet size and date of manufacture, venter components may look more like the one shown below.

4.0 Gas Heat Section Maintenance - RDCB, RDDC, RDDB and RDDC (cont'd)

4.1 Heat Exchanger, Burner, and Venter Maintenance (cont'd)

4.1.1 Instructions for Inspecting/Cleaning the Heat Exchanger and Burner

CAUTION: Use of

eye protection is

recommended.

NOTE: If the installation includes a Model JHUP curb duct furnace, the

inspection and cleaning procedures described in Paragraph 4.1 also apply to the duct furnace. For illustration of a curb duct furnace, see the installation manual, Form I-MAPSIII&IV Cabinet, Paragraph 5.4.3,

Heat Exchanger Maintenance -

The outside of the heat exchanger is accessible by opening the blower section door and sliding the blower out of the unit. Remove any external dirt or dust accumulation. Visually check the heat exchanger for cracks or holes. If a crack or hole is observed, replace the heat exchanger.

NOTE: Inspection of the lower portion of the heat exchanger is done with the burner removed. See the Burner Service section below for information on inspecting the lower portion of the heat exchanger.

Burner Maintenance - This furnace is equipped with a TCORE

style

burner.

Inspect the gas heat section annually to determine if cleaning is necessary. If there is an accumulation of dirt, dust, and/or lint, clean the compartment and follow the instructions below to remove and clean the burner.

CAUTION: Use of eye protection is recommended.

Burner Removal Instructions (Refer to FIGURES 10 and 11.)

1. Shut off the gas supply.

2. Turn off electric supply.

3. Remove the gas heat section access panel.

4. Remove the venter assembly. Disconnect the tubing. Mark and discon-

nect the three venter motor wires at the control board, capacitor wires at the capacitor (if applicable), and ground screw (located on the control panel). The venter motor and wheel assembly only can be removed. To remove the entire venter, also remove the side supports and venter housing.

5. Disconnect the Gas Train - At the gas valves, mark and disconnect the wires. Discon-

nect the gas supply line at the connection outside the furnace. Carefully remove the

burner orices and orice adapter locking nuts. Remove the manifold brackets. Slide

the complete gas train including valves and optional pressure switches out of the unit.

6. Remove Burner Assembly - Remove the screws above and below the burner as-

sembly. Carefully pull the burner assembly out of the cabinet.

FIGURE 10 - Heat Section (panels removed) showing Venter Assembly and Flue Collection Box

Form O-MAPSIII&IV Cabinets A/B/C, Page 22

Page 23

Flame Sensor

Burner Supports

Ignitor Assembly

Orifice

Burner Assembly

Gas Train

FIGURE 11 - Heat Section showing Burner





Assembly and Gas Train

NOTE: A "C" Cabinet heat section is illustrated.

Appearance will vary by Cabinet and size. Maintenance requirements apply to all heat sections including an optional curb duct furnace (JHUP 250 or 300).

Inspect and Clean the Burner

NOTE: If any of the

burner components are damaged or deteriorated, replace the burner assembly.

Inspect the Lower Portion of the Heat Exchanger (with burner assembly removed)

Burner Orice

Check the Ignitor and Flame Sensor

CAUTION: Due to high voltage on the spark wire and electrode, do not touch when energized. See Hazard Levels, page 3.

With the burner assembly removed, shine a ashlight on the burner ribbons. Look for carbon buildup, scale, dust, lint, and/or anything that might restrict ow through the

spaces between the burner ribbons. Holding the burner assembly so that any foreign material will fall away from the burner, use a stiff bristle brush to loosen and remove any foreign material(s). If the burner is excessively dirty, remove both of the burner end caps. Remove the screws that hold the end caps to the burner housing and lightly tap end caps to remove.

Clean all foreign material from the burner and venturi. After the burner is thoroughly cleaned, replace the end caps making certain that they are tight against the burner housing.

At the burner ame entrance of each tube, shine a bright light into each heat exchanger

section. With the light shining into the heat exchanger, observe the outside for visible light. Repeat this procedure with each heat exchanger section. If any light is observed, replace the heat exchanger.

The burner orice usually will not need to be replaced. If ordering a replacement orice only, give BTUH content and specic gravity of gas, as well as the model and serial number of the unit and the orice size. When removing or replacing the burner orice

be careful not to damage the venturi tube and/or the bracket.

Ignitor - Locate the ignitor. Disconnect the wire; remove the

screw and the ignitor. Clean the ignitor assembly with an emery cloth.

Spark gap must be maintained to 1/8". See FIGURE 12. IMPORTANT: When re-assembling, the brown ground wire

must remain attached to the ignitor.

Flame Sensor - Locate the ame sensor on the burner. Disconnect the wires; remove the screws and the ame sensor.

Clean with an emery cloth.

Ignitor

Flame Sensor

FIGURE 12 - Ignitor showing required Spark Gap Measurement

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 23

Page 24

1/2” (13mm) from motor

plate to wheel

NOTE: Measure from

plate and not the gasket.

Venter

Motor

Motor Plate with Gasket

Venter Wheel

4.0 Gas Heat Section Maintenance (cont'd)

4.1 Heat Exchanger,

Burner, and Venter Maintenance (cont'd)

FIGURE 13 - Venter Wheel Position on the Shaft

4.1.2 Maintenance Instructions for the Venter Motor and Wheel

Follow the instructions below to remove the venter assembly. Keep all hardware removed to be used in re-assembling and installing the replacement parts.

Note that during normal operation of this deep modulation control system, the current draw of the venter motor can exceed the full load amp rating on its nameplate. This condition is common when employing electronic wave-chopping technology to reduce the running speed of a single-phase type PSC alternating current motor. The technology reduces energy to the main winding by momentarily interrupting current for a variable amount of time, resulting in a reduction of the motor speed. The increased current is a result of increased slip, which is the difference between the rotation speeds

of the rotor and stator elds. All motors used in MAPS

and built for this unique modulating application and cannot be replaced with a nonapproved motor. All prototype motors have been thoroughly tested with regards to temperature of the windings and bearings at all operating points and ambient conditions and approved by the manufacturer to assure the elevated current does not affect the normal motor life expectancy.

systems are custom designed

Instructions:

1. Turn off the gas and disconnect the electric power.

2. Open the gas heat section access panel and the electrical compartment.

3. Disconnect the three venter motor wires at the control board, capacitor wires at the capacitor (if applicable), and ground screw (located on the control panel).

4. Holding the venter motor, remove the three or four screws that attach the venter motor and wheel assembly. Remove the motor and wheel assembly.

5. Re-assemble with the replacement venter motor and wheel assembly. See FIGURE 13, for proper spacing.

6. Follow the wiring diagram to re-connect the venter wires.

7. Close the access panels. Restore power to the gas heater and turn on the gas. Check for proper operation.

NOTE: Manufacturer recommends replacing venter motor capacitor when replacing venter motor. Use only factoryauthorized replacement parts.

4.1.3 Re-Assemble the Heat Exchanger Panel, Burner, Gas Train, and Venter

Form O-MAPSIII&IV Cabinets A/B/C, Page 24

If replacing venter parts, see FIGURE 3 for proper spacing. If the motor plate gasket is damaged or deteriorated, replace it with P/N 222856.

Remove dirt and grease from the venter housing, the motor casing, and the venter wheel. Venter motor bearings are permanently lubricated.

Instructions to Re-Assemble the Gas Heat Section (Refer back to FIGURES 10 and 11.)

1. Re-attach the Burner Assembly - Slide the entire burner assembly into position. Insert all of the screws along the top and the bottom.

2. Re-attach the Gas Train - Position the gas train so that the orice adapter(s) are through the brackets. Attach the manifold to the manifold brackets. Install the

orice adapter nuts and the gas orice(s) being careful not to damage the venturi

tubes and/or the brackets. Re-connect the wires to the gas valve.

3. Re-attach the venter assembly. (If replacing venter parts, follow the instructions above.) Re-connect the tubing and the wires.

4. Close the access panel.

5. Reconnect the gas supply at the union outside of the cabinet. Leak test the connection with leak detecting solution. Turn on the electric. Turn on the gas. Check for proper operation.

Page 25

4.2 Heat Section Controls

4.2.1 General

The heat section controls are in the low voltage compartment. See FIGURE 1, page 5.

4.2.2 Ignition System for Modulating Gas Control

FIGURE 14A - Ignition Control Module (Deep Modulation Board) in the Electrical Compartment

IMPORTANT: The control module is P/N 257246 for all sizes of MAPS®III&IV Cabinet C heat sections and P/N 258319 on all MAPS®III&IV Cabinet A and B heat sections.

However, the ID plug on each board is unique for each size of heat section. A replacement board will require either a new ID plug or reuse of the ID plug from the board being replaced.

NOTE: Operating and Lockout Error Codes displayed on ignition controller 3-character display (FIGURE 14A) are listed in Troubleshooting Paragraph 7.3.3.

FIGURE 14B - Spark Ignition Board, P/N 257975

The control module is located in the control compartment with an additional board to control spark that is attached directly to the side of the burner. Do not attempt to disassemble either board. However, each heating season check the lead wires for insulation deterioration and good connections.

If replacement is required, these boards must be replaced with identical parts.

ID Plug

3-Character Display

The control has a built-in, self-diagnostic capability. The control continuously monitors its own operation and the operation of the heat section including direct spark ignition, safety and modulating valves, and venter motor speed. The 3-digit display on the control indicates the current system state, warnings, failures, and test modes.

Controller LED Information (displayed on power up)

Display Info (example only) Description C CAb Furnace series or model name, for example, "C cabinet

series" 400 Heat Section Size nAt or LP Fuel type

1.01 Software version

Normal Furnace Operation (LED 3-Character Display in FIGURE 14A)

LED Display Heat Mode Description

OFF Mode (OFF) System Idle - Control board has power, no faults found, no call for heat.

PURGE Mode (Pur)

IGNITION Mode (Ign)

WARM-UP Mode (HEA)

RUN Mode (run) Normal modulating operation.

Ignition Retry (rEt)

System is purging the heat exchanger – No gas on, no ame, inducer runs for the specied purge timings. Purge cycles occur immediately before and after

each burner operation. System is initiating burner operation – Igniter energized, modulating valve moved to ignition setting, gas on. Maintained for the trial-for-ignition period

and the ve second ame stabilization period.

Period between Ignition and Run – System checks completed before modulation control begins.

System has had a failed ignition attempt or has lost ame during burner

operation and is beginning another ignition cycle.

Spark Board is attached

CAUTION: Due to high

to the side of the burner.

voltage on the spark wire and electrode, do not touch when energized. See Hazard Levels, page 3.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 25

Page 26

Orifice

Adapter

Ball Valve

Optional High Gas

Pressure Switch

Transducer

Ball Valve Actuator

Gas

Valve

Optional Low Gas Pressure Switch

Manifold Pressure Tap

4.0 Gas Heat Section Maintenance (cont'd)

4.2 Heat Section Controls (cont'd)

4.2.2 Ignition System

for Modulating Gas Control (cont'd)

Modulating Gas Control Sequence of Operation

1) Call for Heat - The IQ controller calls for heat (there is a closure between "R" and

"W" and at least 2 VDC to the analog input). The ignition system circuit board will check the modulating valve position and move to lightoff position. It checks to see that the limit switch is closed and the pressure switch is open. If the pressure switch is closed, the circuit board will wait indenitely for the switch to open. If the switch is open, the circuit board proceeds to prepurge.

2) Prepurge - After the actuator moves to its lightoff position, the circuit board energizes the venter motor and waits for the pressure switch to close. If the pressure switch does not close at the beginning of a heat cycle, the venter motor will run for two min-

utes, then cycle off for 30 seconds, then on for two minutes, and so forth indenitely.

When the pressure switch is proven closed, the venter motor ramps up to the appropri-

ate lightoff speed and the circuit board begins the prepurge time. If ame is present any time while in prepurge, the prepurge time is restarted. If ame is present long enough

to cause lockout, refer to the Troubleshooting Guide in Paragraph 7.3.2. The ignition system circuit board runs the venter motor for a 30-second prepurge time, then proceeds to the ignition trial period.

3) Ignition Trial Period - The ignition system circuit board energizes the spark and

main gas valve. The venter remains energized. If ame is sensed during the rst 6 seconds, the spark is de-energized. If ame has not been sensed during the rst 6 sec-

onds, the control de-energizes the spark output and keeps the gas valve energized for

an additional one second ame proving period. If ame is not present after the ame

proving period, the control de-energizes the gas valve and proceeds with three ignition

re-tries as specied in “Abnormal Heat Cycle, Ignition Retry”. If ame is present, the

circuit board proceeds to steady heat. After three re-tries, the board will lockout for one hour. It will require a cycling of power to reset before the one-hour limit.

4) Modulating Heat - As long as the call for heat exists, the circuit board not only modulates the gas to precisely meet varying load conditions, but also modulates the

combustion air to maintain stable performance and optimize thermal efciency across

the entire modulating range. Circuit board inputs are continuously monitored to ensure

limit switch is closed and ame is established. When the call for heat is removed, the

ignition system circuit board de-energizes the gas valve and begins postpurge timing.

5) Post Purge - The venter motor output remains on for a 45 second postpurge period

after the system controller is satised.

4.3 Gas Train

See component

identication in

FIGURE 15A, 15B, or 15C.

FIGURE 15A Components in the Heat Section Gas Train - MAPS®III&IV Cabinet A (Heat Section Sizes 100, 150, 200)

Form O-MAPSIII&IV Cabinets A/B/C, Page 26

Location: The gas train is visible with the heat section door open. Service: Carefully remove external dirt from the valves and check the wiring connec-

tions. Annually, in preparation for the heating season, check the single-stage operating

valve to be sure that it shuts gas ow off completely.

If any gas valves or other gas train components need to be replaced, they must be replaced with identical part or factory-authorized replacement.

Page 27

Optional High Gas

Pressure Switch

Optional Low Gas Pressure Switch

Dual, Single-Stage Gas Valve

Ball Valve

Transducer

From Gas

Supply

To Burner

Manifold Pressure Tap

Ball Valve Actuator

Orifice

Adapter

Orifice Adapter

Optional High Gas

Pressure Switch

Transducer

Ball

Valve

Single-Stage Gas Valve

Ball Valve

Actuator

Optional Low Gas

Pressure Switch

Manifold Pressure Tap

FIGURE 15B Components in the Heat Section Gas Train - MAPS®III&IV Cabinet B (Heat Section Sizes 250 and 300)

FIGURE 15C Components in the Heat Section Gas Train - MAPS®III&IV Cabinet C (Heat Section Sizes 400, 500, 600, 700)

Single-Stage Operating Gas Valve - All gas trains have either a single-stage or a dual single-stage safety gas valve.

The gas valve must be checked annually to ensure that it is shutting off gas ow completely; follow the instructions in

box below.

FIGURE 16A - Top View of Single-Stage Gas Valves used on Cabinet A or B Sizes

Adjust Outlet Pressure

1/8” Output Pressure Tap

FIGURE 16B - Top View of Dual Single-Stage Gas Valve used on Cabinet C Heat Section

Pressure Adjustment

1/8” Outlet

Pressure

Tap

Inlet

Pressure Tap

Adjust Outlet Pressure

Inlet Pressure Tap

Instructions:

1. Locate the 1/8" NPT pressure tap or taps on the combination valve.

2. Turn the knob(s) or switch to the OFF position to

Modulating Valve

prevent ow to the manifold. Connect a manometer to

each of the 1/8” outlet pressure taps (1 on the single-

stage valve; 2 on the dual single-stage valve). NOTE: Manometers (uid-lled gauges) with inches water

The gas train also has a ball valve with an actuator to control gas ow. The ball valve

and actuator are located downstream of the regular or dual single-stage valve as shown in FIGURE 17A.

Carefully clean external dirt accumulation from the actuator.

1/8” Output Pressure Tap

3. Use nger(s) to fully block the burner orice(s).

Pressure Adjustment

column scale are recommended. Turn the heater off. On the valve, turn the knob(s) or switch to the ON position.

Continue blocking for several seconds and observe the manometers. If any pressure is indicated, the gas valve is leaking. A leaking gas valve must be replaced before the heater is put back in operation.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 27

1/8” Outlet

Pressure

Tap

Page 28

4.0 Gas Heat Section Maintenance (cont'd)

4.3 Gas Train

FIGURE 17A - Ball Valve and Actuator in Gas Control Option AG70

(cont'd)

FIGURE 17B - Ball Valve with Actuator in Modulating Gas Control (Option AG70) Manifold

Ball Valve with actuator removed

Modulating System Gas Valve (Ball

Inspect the position of the ball valve shaft.

□ In the fully open position, the dash marks on the top of the shaft should be aligned

Valve and Actuator) Adjustment

□ In the fully closed position, the dash marks on the top of the shaft should be

If the ball valve shaft is not properly aligned or if the manifold pressure does not match the settings in the chart below, the ball valve will need to be adjusted.

Manifold Pressures for MAPS®III&IV Gas Modulation System

Ball Valve Shaft

Ball Valve Actuator

Modulates the Gas Flow

Actuator

Set Screw

(shown on the

right or closed

position)

with the gas piping.

aligned at a 90° angle across the gas piping.

Manifold Pressure (" w.c.) Measured

at the Pressure Tap by the Gas Transducer

Cabinet and Heat

Section Size

A-Cab 100 Nat 3.4" w.c. 0.15" w.c.

A-Cab 150 Nat 3.4" w.c. 0.15" w.c.

A-Cab 200 Nat 3.4" w.c. 0.15" w.c.

A-Cab 100 LP 10.0" w.c. 0.5" w.c.

A-Cab 150 LP 10.0" w.c. 0.5" w.c.

A-Cab 200 LP 10.0" w.c. 0.5" w.c.

B-Cab 250 Nat 3.4" w.c. 0.15" w.c.

B-Cab 300 Nat 3.4" w.c. 0.15" w.c.

B-Cab 250 LP 10.0" w.c. 0.45" w.c.

B-Cab 300 LP 10.0" w.c. 0.45" w.c.

C-Cab 400 Nat 3.4" w.c. 0.2" w.c.

C-Cab 500 Nat 3.4" w.c. 0.2" w.c.

C-Cab 600 Nat 3.4" w.c. 0.2" w.c.

C-Cab 700 Nat 3.4" w.c. 0.2" w.c.

Gas

Type

High Setting

100% on ModHeat

Low Setting

0% on ModHeat

To adjust gas modulation follow instructions below:

1. Checking modulation requires a manometer capable of reading to 0.10" w.c. Connect the manometer as instructed in Step 1.f) below. To check and adjust the modulation system, the IQ controller must be in Test Mode. On the control display in the electrical compartment, follow the steps below to enter Test Mode.

Form O-MAPSIII&IV Cabinets A/B/C, Page 28

Page 29

a) Scroll down to Menus and press Enter. b) Enter password (0000) using the INC button and the right arrow button and press Enter. c) Scroll down to the Service Menu and press Enter. d) Scroll down to Test Mode and press Enter. e) Scroll down to Manual Test; press Enter; press the INC button to change the command from OFF to ON; and

press Enter.

f) After the system has completed the shutdown sequence, connect the gas manometer to the manifold pressure

tap next to the transducer (See FIGURE 15 and illustration below). g) On the display, scroll down to Heat Stg 1 and press Enter. h) Scroll down to ModHeat which has a default setting of 100%.

2. With the ModHeat set at 100%, measure the manifold pressure. If the manifold pressure matches the High

Setting value in the chart (page 28), continue to Step No. 3. If the manifold pressure does not match the value in the chart and the ball valve is fully or close to fully open, adjust the pressure screw(s) on the Honeywell valve (See FIGURE 16) until the pressure matches the chart. Note, if the manifold has a dual valve, adjust both pressure screws so that they are the same. When the manifold pressure measured at the manometer matches the pressure listed in the chart, make a note for future reference of the position of the ball valve stem in relation to the dash marks on the actuator.

3. On the display, change the ModHeat setting to 0% modulation and allow the ball valve to go to its lowest setting.

Check the manifold pressure on the manometer. If the manifold pressure matches the Low Setting value in the

chart, skip to Step No. 4. If the manifold pressure does not match the low (0%) value on the chart, the ball valve

will need to be adjusted. Follow these steps:

a) While the unit is still ring at 0% modulation, remove the ball valve actuator. To do this, locate the screw on the

rear of the actuator and remove it. Loosen the actuator set screw (See FIGURE 17B), and carefully remove

the actuator by lifting it straight up. Do not disconnect any wires. b) Using adjustable pliers, slowly turn the ball valve stem until the manifold pressure on the manometer matches

the low setting on the chart.

Important NOTE: If the valve is adjusted too far closed and the ame goes out, let the unit recycle and then

manually open the ball valve to the 100% open position noted in Step No. 2. When the unit is ring at full re,

re-attach the actuator to the ball valve, and repeat the procedure beginning with Step No. 2. c) When the manometer readings match the values in the chart and before re-installing the actuator, the burr

left on the ball valve stem from the previous set screw setting needs to be removed. Either lightly le the burr

on the valve stem to prevent the set screw from returning to the previous position or remove the valve stem,

rotate it 180° so that the set screw contacts the opposite side of the stem, and re-install the valve stem.

d) Re-install the actuator making sure it is level on the ball valve mounting plate. e) Re-check the setting by going to full re (Set ModHeat at 100%) and returning to 0% modulation (Set

ModHeat at 0%). Measure the manifold pressure. The adjusted gas pressure should be close to the value in

the chart on page 28. If not, repeat the procedure.

4. When the settings are in agreement with the chart and testing is complete, remove the manometer. Set ModHeat

to 100%. Scroll the display back to Test Mode and press Enter. Disable Test Mode by pressing the INC button to change the command from ON to OFF; and press Enter.

Gas Manifold Transducer

Optional Gas Pressure Switches

Location: See FIGURE 15. Function: The transducer reads the manifold pressure and sets the venter motor

speed to precisely match the designed combustion settings. Service: If the transducer needs to be replaced, use only a factory-authorized replace-

ment part designed for the purpose.

Location: Low pressure switch is at the entrance to the gas train. The high pressure switch is at the burner end. See FIGURE 15.

Function: Monitors gas pressure and shuts down the heat section if gas pressure becomes too low or too high. The low pressure switch is an auto reset type and is set

at 50% of the maximum manifold pressure. The high pressure switch requires manual reset and is set at 125% of manifold pressure.

Service: There are no replaceable parts and the settings are non-adjustable. If replacement is required, use identical factory-authorized safety switches.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 29

Page 30

4.0 Gas Heat Section Maintenance (cont'd)

4.4 Other Gas Heat Section Controls / Sensors

Combustion Air Proving Switch

Location: See FIGURE 1, page 5, for location. Function: The function of the pressure switch is to verify the cali-

bration of the air pressure sensor mounted on the ignition control board. If the air pressure is not as required, the controller will shut down operation of the heat section.

Service: If it is determined that the pressure switch needs replacing, use only the factory-authorized replacement part that is designed for the model and size of gas heater being serviced.

The ignition board controls the entire combustion process by modulating both the gas and the combustion air supply. Combustion air pressure switches used are listed below.

□ *A "B" Cabinet with 500

mbh of gas heat is a Size 250 heat section plus a Model JHUP-25 curb section duct furnace. Both furnaces have an air proving switch.

□ ** A "C" Cabinet with

1000 mbh of gas heat is a Size 700 heat section plus a Model JHUP-30 curb section duct furnace. Both furnaces have a combustion air proving switch.

Heat Section

Size

100 Nat & Pro 1.30 1.30 0.80 Gray 197078

150 Nat & Pro 1.30 1.30 0.80 Gray 197078

200 Nat & Pro 1.30 1.30 0.80 Gray 197078

250 and

JHUP-250

300 Nat & Pro 1.40 1.40 1.15 Brown 201160

400 Natural 2.70 2.70 1.40 Red 201159

500 Natural 2.90 2.90 1.40 Red 201159

600 Natural 3.35 3.35 2.00 White 234054

700* Natural 3.40 3.40 2.00 White 234054

JHUP-300* Natural 0.70 0.70 0.50 Orange 196388

Gas

Natural 1.15 1.15 0.80 Gray 197078

Propane 1.30 1.30 1.05 Brown 201160

Light Off (Cold) Equilibrium (Hot)

Full Rate

Setpoint

OFF

Label Color

Switch

P/N

DANGER

Safe operation requires proper venting ow. Never bypass the combustion air

proving switch or attempt to operate the heat section without the venter running

and proper ow in the vent system. Hazardous condition could result. See Hazard

Levels, page 3.

Limit Control

Location: The limit control is located in the farthest downstream heater compartment

with the capillary sensor extending across the discharge side of the heat exchanger. NOTE: If the installation includes an Option JHUP-30 curb section duct furnace, it also has a limit control. See location in installation Form I-MAPSIII&IV, Paragraph 5.4.3

Function: The limit control is a temperature sensitive safety device. If the temperature setting of the limit control is exceeded, the controller will shut down heat section operation.

Service: The limit switch will automatically reset when the temperature drops below the setpoint. However, the cause for the limit activating should be found and corrected. If it is determined that the limit control needs replacing, use only a factory-authorized replacement part that is designed for that heat section.

5.0 Electric Heat

Section Maintenance -

Turn off the power locking the disconnect switch. Allow the heating elements to cool.

Models RECB, RECC, REDB and REDC

Form O-MAPSIII&IV Cabinets A/B/C, Page 30

WARNING

CAUTION: Wearing eye protection is recommended when

cleaning the heating elements and cabinet.

Page 31

Electric Heating Elements and Controls

Service: Check the heating elements at the beginning of the heating season. The ele-

ments are assembled and attached to the electrical panel that is visible on the inner side of the electric heat section. Slide the panel out to access the elements. Carefully clean all dust and dirt from the heating elements using a brush or steel wool. With a vacuum or air hose, clean the inside of the cabinet especially the bottom and sides where dirt and dust will accumulate. If a replacement is needed, order a complete heat section assembly.

Location: See the control location illustration in FIGURE 1, page 5, and FIGURE 18, below, the additional high voltage panel in the electric heat section. Quantities and types of distribution blocks, fuses, and contactors depend on the size of the unit.

If replacement parts are required, check with your distributor and use only factoryauthorized replacements.

FIGURE 18 - High Voltage Panel in the Electric Heat Section

- Models RECB, RECC, REDB, and REDC

Distributor Blocks are on this panel. (qty varies by size and voltage)

6.0 Energy Recovery Module, Option ER1

Grounding Lug

High Voltage Panel in Electric Heat Section

If the MAPS® unit is equipped with an optional energy recovery module (Option ER1A, ER1B, or ER1C), there are additional maintenance and service procedures unique to the energy recovery wheel.

Refer to the energy recovery module manual, Form I-MAPSIII&IV-ER, for required maintenance instructions and service information.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 31

Page 32

7.0 Troubleshooting

7.1 Troubleshooting

- Refrigeration

(All Models)

should only be performed by a qualied HVAC technician.

See Control Instructions, Form CP-MAPSD15/16/17/18, for information on the unit controller.

General Refrigeration Circuit - applies to all Models

SYMPTOM POSSIBLE CAUSE REMEDY

A. Compressor will not start.

B. Compressor starts but cuts out on low pressure (low pressure switch activates at 35 psig.)

C. Compressor starts but cuts out on high pressure switch.

D. Compressor cuts out on thermal overload.

E. Noisy compressor.

F. Noisy unit operation.

G. High suction pressure

1. Power off, loose electrical connections or fuse open.

2. Compressor contactor not closing. 2. Check voltage to contactor coil, transformer, slave relay, system. Replace

3. Internal compressor thermal overload open. 3. If compressor is hot, allow 2 hours to cool. See D. below.

4. Compressor defective. 4. Check compressor for electrical failure. Compressor may be seized; check

5. High or low pressure switch open or defective. 5. If manual reset (high pressure), reset switch. (Switch opens at 600 psi and will

1. Low refrigerant charge. 1. Check subcooling; see Paragraph 3.5.

2. Airow restricted. 2. Check for dirty evaporator coil, dirty lters, dampers closed, iced evaporator

3. Restriction in refrigerant line. 3. Check subcooling and superheat (Paragraph 3.5). Check operation of the

4. Defective low pressure switch. 4. Check switch (opens 35 psi; closes 50 psi). If defective, replace low pressure

1. Refrigerant overcharge. 1. Check subcooling; see Paragraph 3.5.

2. Condenser fan motor defective. 2. Check fan motor.

3. Condenser coil inlet obstructed or dirty. 3. Check coil and inlet clearances and for possible air recirculation.

4. Air or non-condensables in system. 4. Check high side equalized pressure reading with equivalent outdoor

5. Defective high pressure switch. 5. Check switch (opens 600 psi; proof 700 psi; manual reset allowed below 400

6. Restriction in discharge or liquid line. 6. Check subcooling and superheat (Paragraph 3.5). Check operation of thermal

1. Low voltage. 1. Check voltage.

2. Sustained high discharge pressure. 2. Check running amperage and conditions described in I.

3. High suction and discharge pressures. 3. Check thermal expansion valve operation, check for air in system.

4. Defective compressor overload. 4. If compressor is hot, allow compressor to cool for two hours. Recheck for

5. Improper refrigerant charge. 5. Check subcooling (Paragraph 3.5).

6. Bearings or pistons too tight. 6. Check for low oil level.

7. Allow time for compressor to cool. 7. Check dome temperature of the compressor.

1. Reverse rotation. 1. Check at startup. If the suction pressure rises and discharge pressure drops,

2. Refrigerant overcharge. 2. Check pressures and subcooling (Paragraph 3.5).

3. Liquid oodback. 3. Check thermal expansion valve setting. Check subcooling for refrigerant

4. Tubing rattle. 4. Dampen tubing vibration by taping or clamping. Carefully bend tubing away

5. Compressor defective. 5. Check internal parts. Replace defective parts or compressor.

1. Blower rotational noise. 1. Check blower, motor and drive for faulty adjustment or noisy bearings, loose

2. Air noise. 2. Check ductwork. Air velocity too high.

3. Chattering contactor. 3. Check for adequate control voltage; check for shorts or breaks; check contact

4. Tubing rattle. 4. Dampen by taping or clamping, carefully bend tubing away from contact when

1. Excessive load on evaporator coil. 1. Check superheat (Paragraph 3.5). Check for high entering wet bulb

2. Compressor is unloaded. 2. Check head pressure. Check thermal expansion valve. If valve is not

3. Expansion valve bulb not secured to suction line or valve defective.

NOTE: Unit is equipped with a phase loss/phase reversal control. If system does not start, check phase of electrical supply.

1. Check disconnect switch, fuses and wiring. Replace parts or repair as necessary

parts as necessary.

refrigerant. If necessary, replace compressor.

not reset above 400 psi.) If auto reset (low pressure) does not reset and everything else is OK, replace low pressure switch, P/N 216380.

coil, and/or improper belt. Check motor amps. Check duct design.

thermal expansion valve. Check for pressure drop across the lter drier.

switch, P/N 216380.

temperature.

psi). If defective, replace high pressure switch, P/N 216379.

expansion valves.

open circuit.

shut down the compressor. Switch the 3-phase wiring connections.

overcharge (Paragraph 3.5).

from contact where possible.

parts, and/or blower out of balance.

points.

possible.

temperature. Check for excessive air.

functioning properly, check pressure drop across lter drier.

3. Check the thermal expansion valve; ensure bulb is attached properly and

insulated

Form O-MAPSIII&IV Cabinets A/B/C, Page 32

Page 33

H. High discharge pressure.

I. Suction pressure is too low.

J. Head pressure too low.

K. Compressor short cycles.

L. Running cycle is too long or unit operates continuously.

M. Supply air temperature is too high.

N. Supply air temperature is too low. O. Liquid line is too hot.

1. Refrigerant overcharge 1. Check subcooling. (Paragraph 3.5) Adjust refrigerant charge.

2. Thermal expansion valve setting 2. Check superheat and adjust valve as needed.

2. Air inlet to condenser dirty or obstructed. 3. Check for proper clearances and possible air recirculating.

4. Condenser fan motor defective. 4. Check condenser fan motor(s).

1. Refrigerant undercharge. 1. Check subcooling. (Paragraph 3.5) Add refrigerant as needed.

2. Thermal expansion valve setting 2. Check superheat and adjust valve as needed.

3. Blower running backward. 3. Interchange any two wires from 3 phase disconnect.

4. Loose blower, pulley, or belts. 4. Check drive pulley alignment and belt tension.

5. Dirty lter. 5. Check lter and evaporator coil.

6. Too little air ow or low entering air temperature. 6. Check airow and entering air wet bulb conditions.

7. Restriction in suction or liquid line. 7. Check refrigerant circuit for restriction.

1. Insufcient refrigerant charge. 1. Check subcooling (Paragraph 3.5). Check for leak. Repair and add refrigerant.

2. Defective or improperly adjusted expansion valve. 2. Check superheat (Paragraph 3.5) and adjust thermal expansion valve.

3. Low suction pressure. 3. See “I. Suction pressure too low” above.

4. Defective compressor. 4. See "G. High suction pressure” above.

1. Improper refrigerant charge. 1. Check subcooling and superheat. (Paragraph 3.5)

2. Defective high or low pressure control. 2. Check high or low pressure switch.

3. Liquid oodback. 3. Possible tight bearings, see above.

4. Defective expansion valve. 4. Check superheat and thermal expansion valve.

5. Poor air distribution. 5. Check ductwork for recirculating.

6. High discharge pressure. 6. See “H. High discharge pressure” above.

7. Leaking discharge valves in compressor. 7. See “G. High suction pressure” above.

1. Refrigeration undercharged. 1. Check subcooling (Paragraph 3.5) and add refrigerant.

2. Dirty lter or evaporator coil. 2. Check lter, coil, and airow. Clean and/or replace.

3. Dirty or clogged condenser coil. 3. Check coil and airow. Clean.

4. Air or other non-condensables in system. 4. Check equalized high side pressure with equivalent outdoor temperature.

5. Defective compressor. 5. See “G. High suction pressure” above.

6. Restriction in suction and liquid line. 6. Check for restrictions in refrigerant circuit.

7. Control contacts stuck. 7. Check wiring.

1. Refrigerant undercharge or leak in system. 1. Check subcooling (Paragraph 3.5). Check for leak. Repair and add refrigerant.

2. Evaporator plugged with dirt or ice. 2. Check evaporator, airow, and lter. Clean.

3. Improperly adjusted or defective expansion valve. 3. Check superheat (Paragraph 3.5) and adjust thermal expansion valve. Check expansion valve bulb placement and insulation.

4. Defective compressor. 4. Check compressor for proper operation.

5. High discharge pressure. 5. See “H. High discharge pressure” above.

6. Airow is too high. 6. Check external static pressure.

1. Airow is too low. 1. Check evaporator coil; check lters; check for closed dampers or grills; check drive for loose parts, belts, or misalignment; and check external static pressure.

2. Return air temperature too low. 2. Check entering air wet bulb conditions.

1. Refrigerant undercharge. 1. Check subcooling.

2. High discharge pressure. 2. See H. above.

7.2 Compressor Digital Controller Troubleshooting

- all MAPS

Models

NOTE: To identify MAPS®IV

Models, see Paragraph 1.0.

General - The digital controller is located in the electrical compartment and acts as the interface between the digital compressor and the unit controller. If the unit interface display indicates critical Alarm Code 17, Modulating Capacity Compressor Failure, check the LED lights on the digital controller. The alert code (red LED ashes) on the digital controller remains active and the compressor de-energized until the reset conditions have been met or the 24VAC power is cycled off and on. All Codes except 6 result in compressor (contactor and unloader valve) being de-energized.

Compressor Digital Controller LED’s

LED State

Color CODE

Green Solid Power (24VAC present at

Green. Flashing Anti-short cycle timer is

Yellow Solid Unloader (Solenoid valve

Red Not lit No abnormal operation

Red 2 Flashes High Discharge

Indicates Additional Information

power terminals)

active

is energized; compressor

capacity is 0.)

alerts

Temperature Alert (thermistor temperature above 268°F or thermistor is short circuited)

Modulating capacity compressor starts only when demand signal input is above 1.45 VDC and no

ALERTS (red LED ashes) are active.

Modulating capacity compressor always unloads for 0.1 second at startup.

Modulating capacity compressor will be allowed to restart after a 30-minute delay and after the thermistor temperature is below 250°F. Compressor will lockout after 5 alerts within 4 hours and can only be reset by cycling the 24VAC power off and on.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 33

(continued)

Page 34

7.2 Compressor Digital Controller Troubleshooting

- all MAPS

Models (cont'd)

Compressor Digital Controller LED’s (cont'd)

Red 3 Flashes Compressor Protector

Trip (demand signal >1.44VDC & no compressor current)

Red 4 Flashes Locked Rotor Alert Locked rotor sensed by controller on four consecutive

Red 5 Flashes Demand Signal Loss

(below .5VDC)

Red 6 Flashes Discharge Thermistor

Fault (no signal being received)

Red 7 Flashes Unloader Solenoid Valve

Fault

Red 8 Flashes Compressor Contactor

Fault (compressor running on less than

1.44VDC demand signal)

Red 9 Flashes Low 24VAC supply

to controller (below

18.5VAC)

All Solid Digital compressor

controller failure

All Flashing 24VAC Supply too low for

operation

Possible causes - internal overload, fuse or breaker, compressor wiring. After 2-minute anti-short cycle timer the controller will attempt to restart the compressor as long as demand is above 1.44VDC. No lockout feature.

start-ups. Lockout occurs and can only be reset by cycling 24VAC power off and on.

When demand signal input rises above 0.5VDC, alarm code will reset. When demand reaches above 1.44VDC and anti-short cycle timer has timed out, modulating capacity compressor will restart.

Modulating compressor capacity limited to 50%.

Re-connect or replace thermistor.

Modulating compressor will run unloaded. Alarm will be reset when current is no longer detected while system demand signal is below 1.44VDC.

Alarm will reset when supply voltage to controller rises above 19.5VAC.

The installed digital compressor controller can be tested to verify that it is working properly. In each test, 24VAC must be supplied to 24VAC and 24COM. For output test, 24-250VAC must be supplied to L1 and L2. Input Tests - 1) Thermistor Input - Disconnect thermistor (T1 & T2); LED should display Code 6.; and 2) Demand Input - Disconnect unit controller (C1 & C2); LED should display Code 5 unless a previous alert code was present.

Output Tests - 1) Contactor Output - while the controller is powered off (no supply voltage to 24VAC and

24COM), disconnect signal wire from C1 & C2; add jumper wires from P3 to C2 and from P1 to C1; re-apply

power to 24VAC and 24COM. If functioning normally, same voltage should be read across M1 and M2 as across L1 and L2, unless an LED ALERT code is present.; and 2) Unloader Output - while controller is modulating the unloader solenoid (whenever the yellow LED is lit), voltage across U1 and U2 should be the same as L1 and L2.

7.3 Troubleshooting the Heat Section

7.3.1 General Troubleshooting - Electric Heat Section - RECB, RECC, REDB, & REDC

PROBLEM PROBABLE CAUSE REMEDY Unit does not

operate

Fan operates but element does not heat

Insufcient

heat

Form O-MAPSIII&IV Cabinets A/B/C, Page 34

1. No power to unit 1. Turn on power; check supply fuses or main circuit breaker.

2. Blown fuses 2. Check and replace if necessary.

3. Defective or incorrect wiring. 3. Check wiring and connections. Refer to wiring diagram provided with unit.

4. Defective or burned out control transformer 4. Check secondary voltage with voltmeter. Replace if necessary.

1. Dirty lters 1. Check lters and clean or replace if necessary.

2. Defective air proving switch 2. Check and replace if necessary.

3. Blown element fuses 3. Check and replace element fuses if necessary.

1. Burned out element 1. Turn off power and check element resistance with ohmmeter. Replace if open.

2. Blown fuses 2. Check and replace if necessary.

3. Cycling on limit control 3. a) Check air throughput (temperature rise). b) Check motor rpm against nameplate rating. Replace motor if speed is too slow. c) Defective limit control. Check wiring and connections. Check continuity through

control and replace if necessary.

4. Defective or incorrect wiring. 4. Check wiring and connections. Refer to wiring diagram provided with unit.

Page 35

7.3.2 General Troubleshooting - Gas Heat Section - Models RDCB, RDCC, RDDB & RDDC

PROBLEM PROBABLE CAUSE REMEDY Venter motor

will not start

Burner will not light

Burner cycles on and off

No heat (Heater Operating)

Venter motor will not run

Venter motor cuts out on overload

1. No power to unit. 1. Turn on power; check supply fuses or main circuit breaker.

2. No 24 volt power to ignition system circuit board. 2. Turn up thermostat; check control transformer output.

3. Integrated circuit board fuse blown. 3. Correct cause; replace fuse.

4. No power to venter motor. 4. Tighten connections at circuit board and/or motor terminals.

5. Integrated circuit board defective. 5. Replace integrated circuit board.

6. Defective venter motor or capacitor 6. Replace defective parts. Recommend replacing capacitor when replacing

1. Manual valve not open. 1. Open manual valve.

2. Air in the gas line. 2. Bleed gas line (initial startup only).

3. Gas pressure too high or too low. 3. See installation manual, Form I-MAPSIII&IV, Paragraph 9.2.1.

4. No Spark: 4. a) Loose wire connections. a) Be certain all wire connections are solid. b) Transformer failure. b) Be sure 24 volts is available. c) Incorrect spark gap. c) Maintain spark gap at 1/8". d) Spark cable shorted to ground. d) Replace worn or grounded spark cable. e) Spark electrode shorted to ground. e) Replace if ceramic spark electrode is cracked or grounded. f) Burner not grounded. f) Make certain circuit board is grounded to ignitor. g) Ignition system circuit board not grounded. g) Make certain circuit board is grounded to furnace chassis. h) Unit not properly grounded. h) Make certain unit is properly eld grounded to earth ground and properly

i) Ignition system circuit board fuse blown. i) Correct cause; replace fuse. j) Modulation system out of acceptance range j) Review error codes on board; refer to pages 36-39. j) Faulty circuit board. j) If 24 volt is available to the circuit board and all other causes have been

5. Lockout device interrupting control circuit by above causes.

6. Combustion air proving switch not closing 6.

7. Faulty combustion air proving switch. 7. Replace combustion air proving switch.

8. Valve not operating. 8. a) Defective valve. a) If 24 volt is measured at the valve connections and valve remains closed,

b) Loose wire connections b) Check and tighten all wiring connections.

9. Circuit board does not power valves. 9. a) Loose wire connections. a) Check and tighten all wiring connections. b) Flame sensor grounded. b) Be certain ame sensor lead is not grounded or insulation or ceramic is

c) Incorrect gas pressure. c) See installation manual, Form I-MAPSIII&IV, Paragraph 9.2.1. d) Cracked ceramic at sensor. d) Replace sensor.

1. Gas pressure too high or too low. 1. See installation manual, Form I-MAPSIII&IV, Paragraph 9.2.1.

2. Burner not grounded 2. Make certain integrated circuit board is grounded to ignitor.

3. Circuit board not grounded. 3. Make certain integrated circuit board is grounded to furnace chassis.

4. Faulty integrated circuit board 4. If 24 volt is available to the circuit board and all other causes have been

5. Combustion air proving switch not closing. 5.

6. Faulty combustion air proving switch. 6. Replace combustion air proving switch.

7. Flame sensor grounded. 7. Be certain ame sensor lead is not grounded or insulation or ceramic is

8. Cracked ceramic at sensor. 8. Replace sensor.

9. Incorrect polarity. 9. Reverse line volt leads to integrated circuit board.

1. Incorrect valve outlet pressure. 1. Check valve outlet pressure. See Installation Form I-MAPSIII&IV,

2. Cycling on limit control. 2. Check air throughput.

1. Circuit open. 1. Check wiring and connections.

2. Defective integrated circuit board. 2. Replace board.

3. Defective motor. 3. Replace motor.

1. Low or high voltage supply. 1. Correct electric supply.

2. Defective motor or capacitor. 2. Replace defective parts. Recommend replacing capacitor when replacing

motor. See Paragraph 4.1.2.

phased (L1 to hot lead L2 to neutral).

eliminated, replace board.

5. Reset lockout by interrupting control.

a) Remove obstructions from vent. b) Replace faulty tubing to pressure switch.

replace valve.

not cracked. Replace as required.

eliminated, replace board.

a) Make sure unit is properly vented. b) Remove obstructions from vent. c) Replace faulty tubing to pressure switch.

not cracked. Replace as required.

Paragraph 9.2.1.

motor. See Paragraph 4.1.2.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 35

Page 36

7.3 Troubleshooting the Heat Section (cont'd)

7.3.3 Troubleshooting - Modulating Control Module used on Cabinet A, B, and C Gas Heat Sections

The control that operates the furnace in a MAPS®III Cabinet A, B, and C has a built-in, self-diagnostic capability. The control continuously monitors its own operation and the operation of the system. The LED on the control indicates the current state, warnings, failures, and test modes.

Normal Furnace Operation Display

LED Display Heat Mode Description

OFF Mode (OFF) System Idle - Control board has power, no faults found, no call for heat.

PURGE Mode (Pur)

IGNITION Mode (Ign)

WARM-UP Mode (HEA) (Board Self Check)

RUN Mode (run) Normal modulating operation.

Ignition Retry (rEt)

System is purging the heat exchanger – No gas on, no ame, venter motor runs for the specied purge

timings. Purge cycles occur immediately before and after each burner operation. System is initiating burner operation – Ignitor energized, modulating valve moved to ignition setting, gas

on. Maintained for the trial-for-ignition period and the ve-second ame stabilization period.

Period between Ignition and Run – System checks completed before modulation control begins.

System has had a failed ignition attempt or has lost ame during burner operation and is beginning

another ignition cycle.

Deep Modulation (Option AG70) Ignition Board is in the Control Compartment (See FIGURE 1, page 5.)

IQ Controller Signal Input Terminals (J4)

Main Board Supply Power Input

Spades (L1 T1 and L2 T5)

Board Status

Voltage Output

to IQ (J7)

Board Power

and Signal (J6)

Control Board

Fuse (3A)

Plug Connection for Board Control Points (J8)

• Ball Valve Actuator Power, Drive Voltage, and Feedback Signal

• Off Board Digital Venter Air Pressure Switch and Unit

Primary Limit Switch

Gas Manifold PSI Transducer Plug 3-wire (red, black, and green) Wiring Connection (J13)

On board Air Pressure Sensor for Monitoring Inducer Pressure. Venter Sensing Tubing is connected from Venter housing to

J9, J10, J3, and J2 are not currently used.

"LO" pressure input point on air sensing transducer.

Inducer Motor Main Power Connection Spades (IND-L2 T3 and IND-L1 T2)

Inducer Motor Capacitor Spade Connection (AUX-L2 T6)

Flame Sensor Spade Connection

(T8)

ID Plug (unique by heat section size)

3 Character LED Display used to show deep modulation board codes for status, alarm, and error information.

Form O-MAPSIII&IV Cabinets A/B/C, Page 36

Page 37

Gas Heat Section Modulating Control FUNCTIONAL ALERTS

Code Alert Description Probable Causes Solutions

Failed ignition attempt (AO1)

Maximum number of allowed retries not met

Lost Flame (AO2)

Insufcient

Combustion Air (AO3)

Furnace functional

Limited Low Fire (AO4)

Weak Flame Signal (AO5)

The ame could not be

established during the trial for ignition period. This alert indicates the maximum number of retries has not been exceeded and furnace operation will continue with another ignition attempt.

The ame sensor signal has been lost after ame is

established during a call for heat. This alert is displayed during the RECYCLE period prior to the next ignition attempt.

Furnace cannot achieve

desired combustion air ow

due to blockage or high altitude operation resulting in a de-rate of the furnace.

Automatic adaptive program is currently limiting the lower range of modulation at avoid

ame loss at minimum re

conditions. The alert is displayed during the run

cycle once a ame-out

condition has triggered the Limited Low Fire function. This function is reset by cycling power to the board.

The ame signal level is

less than optimal for this furnace. Maintenance of the

ame sensing components

is advised.

See LOCKOUT ERRORS section, pages 38-39.

A. Flame sensor coated 1. Clean ame rod sensor.

B. Flame sensor improperly mounted or grounded

C. Unstable ame pattern 1. Verify that the spacing between the burner body and the burner shield

D. Insufcient intermediate

gas manifold pressure through main gas safety valve

E. Insufcient gas manifold

pressure to burner through modulating ball valve assembly

A. High altitude operation 1. Normal operation. Furnace automatically de-rates for high altitude

B. Partially blocked vent 1 Check air inlet and outlet for blockage.

C. Leak in sensing hose 1. Check sensing hose for cracks, crimps, or loose connections. D. Low Line Voltage 1. Check the line voltage to the control board. Voltage should be within

E. Faulty venter assembly 1. Verify that the venter assembly is functioning properly by referring to

A. Low gas line pressure 1. Ensure gas supply is connected to furnace and check for proper line

B. Insufcient intermediate

gas manifold pressure through gas safety valve

C. Faulty burner operation 1. Check burner orice for proper size and blockage.

D. Faulty ame sensor 1. Check ame rod wiring and connections.

E. Improper alignment of the modulating actuator and the gas ball valve.

F. Blocked or improper venting

G. Improper jumper connection on IQ UI-12 causing AO-4 to show on BacView as alarm and disables heat sequence.

A. Flame sensor coated 1. Clean ame rod sensor. B. Flame sensor improperly mounted or grounded C. Unstable ame pattern 1. Verify that the spacing between the burner body and the burner shield

in the

See in the LOCKOUT ERRORS section, pages 38-39.

1. Check ame sensor wiring integrity and ceramic for cracks.

2. Re-install / replace ame sensor.

is equal across the entire length of the burner.

2. Check that the seals between the heat exchanger header and heat

exchanger tubes are sound; refer to Paragraph 4.1.1.

3. Ensure that the heat section door gasket is in place and the doors are properly aligned

1. Check for faulty gas valve wiring.

2. Check 24 VAC to gas valve assembly.

3. Check inlet pressure to safety gas valve.

4. Check outlet pressure from the safety gas valve.

5. Replace safety gas valve if faulty.

1. Check voltage to gas valve actuator. (2-10 VDC depending on model)

2. Check alignment and set screw connection between ball valve and actuator. See Paragraph 4.3.

conditions.

2. Check venting conguration for excessive venting length, improper

sizing, etc.

10% of nameplate.

the sensing pressure chart on page 30.

pressure.

1. Check for faulty gas valve wiring.

2. Check 24 VAC to gas valve assembly.

3. Check inlet pressure to safety gas valve.

4. Check outlet pressure from the safety gas valve – adjust as needed.

5. Replace safety gas valve if faulty.

2. Check for proper alignment of ame rod.

3. Clean ame rod sensor.

1. Check that the alignment of the actuator to the ball valve is correct. The valve must be in the fully open position when the actuator is energized (ACTUATOR DRIVE = 9.6 VDC or greater).

2. Ensure that the setscrew on the actuator is tightened to the ball valve stem.

1. Check air inlet and outlet for blockage.

2. Check venting conguration for excessive venting length, improper

sizing, etc.

1. Verify that the IQ heating feedback input is set to receive the ignition board voltage output of 0-10VDC from terminals J7 by making sure jumpers are set to receive 0-10VDC signal on UI-12 of the IQ controller.

1. Check ame sensor wiring integrity and ceramic for cracks.

2. Re-install / replace ame sensor.

is equal across the entire length of the burner.

2. Check that the seals between the heat exchanger header and heat

exchanger tubes are sound; refer to Paragraph 4.1.1.

3. Ensure that the heat section door gasket is in place and the door is properly aligned.

(continued)

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 37

Page 38

7.3 Troubleshooting the Heat Section (cont'd)

7.3.3 Modulating Control Module on Cabinet A, B, C Gas Heat Sections (cont'd)

Gas Heat Section Modulating Control LOCKOUT ERRORS

Code Alert Description Probable Causes Solutions

Ignition Board Failure (888)

Failed Ignition (EO1)

Maximum Retries (3) Exceeded

Primary Limit / Fuse Failure (EO2)

Modulation Valve Failure (EO3)

Air Sensor Failure (EO4)

Pressure Sensor Reading Low

Ignition board start-up checks have detected an error.

The ame could

not be established during multiple trialfor-ignition periods (3). The maximum number of retries has been exceeded and the furnace is in a lockout condition. System Shutdown alarm lockout will need to be reset through BacView interface or IQ controller will need to be power cycled.

The control board safety fuse has blown or the primary temperature limit has opened indicating safe operating temperatures for this furnace have been exceeded.

The control lost the position feedback from the modulating gas valve actuator.

The air sensor reading is too low for operating conditions or the air pressure switch closed when the sensor

indicates low ow

The pressure switch MUST be open prior to venter activation.

A. Faulty transformer 1. Check 24-volt transformer for correct output.

2. Check connections and wiring to control board and other components connected to the 24 volt source.

3. Replace if necessary.

B. Faulty control board 1. Turn off power to the furnace, wait 30 seconds and turn power

A. Insufcient gas line pressure 1. Insure gas supply is connected to furnace and check for proper

B Gas valve control turned “OFF” 1. Turn gas valve to the “ON” position

C. No spark from direct spark ignition

D. Insufcient intermediate gas

manifold pressure through gas safety valve

D. (cont'd) 4. Check outlet pressure from the safety gas valve – adjust as

E. Insufcient gas manifold

pressure to burner through modulating ball valve assembly

F. Burners do not light 1. Check spark rod assembly for proper location, spark gap, etc.

G. Burners light and remain lit for about 5 seconds

A. Improper circulating airow 1. Check lter / replace if dirty.

B. Primary limit switch failure 1. Check for an open primary limit switch at ambient temperature. C. Fuse is blown 1. Check and replace fuse on the board.

D. Faulty primary limit switch wiring A. Faulty modulation valve actuator wiring

B. Modulation valve actuator failure

A. Faulty wiring or connections 1. Check pressure switch wiring.

B. Faulty pressure switch 1. Replace pressure switch.

C. Faulty pressure sensor, located on the board

back on. Re-try ignition sequence and see if the system responds.

2. Replace control board if necessary.

line pressure.

1. Check ignition voltage (115 VAC from board to transformer) and wiring.

2. Check 24 VAC transformer for DSI board.

1. Check for faulty gas valve wiring.

2. Check 24 VAC to gas valve assembly.

3. Check inlet pressure to safety gas valve.

needed.

5. Replace safety gas valve if faulty.

1. Check voltage to gas valve actuator. (7 – 10 VDC depending on model)

2. Check alignment and setscrew connection between ball valve and actuator (See procedure in Paragraph 4.3.).

2. Verify that the spacing between the burner body and the burner shield is equal across the entire length of the burner.

3. Check burner orice for proper size and blockage.

1. Check ame rod wiring and connections.

2. Check for proper alignment of ame rod.

3. Clean ame rod sensor.

2. Check for improperly sized duct system.

3. Check for faulty blower motor.

4. Check for faulty blower motor wiring.

2. Make sure fuse socket is tight, crimp fuse terminals if necessary.

1. Check primary limit wiring continuity from the switch to the control board.

1. Ensure wiring is connected per unit wiring diagram.

2. Check for loose pins or bad connections.

3. Check for frayed wiring or shorts to ground.

1. Ensure actuator has 24 V power.

2. Ensure actuator is receiving signal from the control board (2-10 VDC).

3. Check for actuator feedback to the control board (2-10 VDC)

2. Check inducer wiring.

3. Check for plugged or disconnected vacuum hoses.

1. Replace board.

Air Sensor Failure (EO5)

Pressure Sensor Reading High

Form O-MAPSIII&IV Cabinets A/B/C, Page 38

The air sensor reading is too high when the venter is off or the air pressure switch open when the sensor

indicates high ow.

The pressure switch MUST close to initiate an ignition sequence.

A. Faulty wiring or hose connections

B. Blocked or improper venting 1. Check air inlet and outlet for blockage.

C. Faulty pressure switch 1. Replace pressure switch.

1. Check pressure switch wiring.

2. Check venter motor wiring.

3. Check for broken or disconnected vacuum hoses.

2. Check venting conguration for excessive venting length,

improper sizing, etc.

Page 39

Gas Heat Section Modulating Control LOCKOUT ERRORS (cont'd)

Code Alert Description Probable Causes Solutions

Gas Sensor Failure (EO6)

Pressure Sensor Reading Low

Gas Sensor Failure (EO7)

Pressure Sensor Reading High

Improper Flame Signal (EO8)

No Firing Rate Input (EO9)

Invalid I.D. Plug (Eid)

The gas transducer reading is too low compared to the expected value for the modulating gas valve actuator position.

When the furnace is operating at 75% or higher -- greater than 8 VDC analog input voltage - the manifold pressure sensor must read 1.4" w.c. or higher

The gas transducer reading is too high compared to the expected value for the modulating gas valve actuator position.

When the furnace is operating at 75% or lower - less than 8 VDC analog input voltage -- the manifold pressure sensor must read 2.8" w.c. or lower.

Control senses ame

present when the gas valve is commanded off.

Call for heat is sensed (R & W closed) but

ring rate is below dened voltage

threshold for furnace operation.

The installed I.D. plug is not valid for this control board.

A. Modulating actuator/ball valve not properly aligned B. Line pressure too low 1. Ensure line pressure is properly adjusted for the gas and

C. Intermediate regulated pressure to low

D. Wrong gas pressure sensor installed. E. Gas pressure sensor faulty 1. Ensure gas manifold transducer is installed properly and wired

A. Modulating actuator / ball valve not properly aligned B. Line pressure too high 1. Ensure the line pressure is properly adjusted for the gas and

C. Intermediate regulated pressure too high

D. Wrong gas pressure sensor installed

E. Gas pressure sensor faulty 1. Ensure gas sensor is installed properly and wired per the unit

A. Flame remains lit in “Off” cycle 1. Gas valve leaks - check wiring to remove continuous 24V to gas

A. Faulty wiring into the “Analog +” and “Analog –“ terminals

B. No signal from source. 1. Check ring rate input voltage – must be greater than 1.5 VDC.

A. Incorrect I.D. plug installed 1. Ensure I.D. plug is correct for the furnace – check label.

1 Perform modulating system gas valve alignment procedure; see

Paragraph 4.3.

application. Correct as needed.

1. Ensure the safety gas valve(s) are properly adjusted to the

specied outlet pressure. Adjust per the installation instructions as

necessary.

1. Ensure the proper gas transducer - either natural gas or propane

- is installed. Replace as needed.

per the unit wiring diagram. Replace as necessary.

1. Perform modulating system gas valve alignment procedure; see

Paragraph 4.3.

application. Correct as necessary.

1. Ensure the safety gas valve(s) are properly adjusted to the

specied outlet pressure. Adjust per the installation instructions as

necessary.

1. Ensure gas sensor -- either natural or propane -- is installed. Replace as necessary.

wiring diagram. Replace as necessary.

valve.

2. Gas valve is stuck open – remove, repair, or replace gas valve.

1. Ensure wiring is connected per unit wiring diagram.

2. Check for loose pins or bad connections.

3. Check for frayed wiring or shorts to ground.

2. Troubleshoot controller providing ring rate input to the deep

modulation ignition control board.

2. Ensure I.D. plug is properly inserted into the mating connector on the control board.

3. With the I.D. plug installed, cycle power to the furnace. The board will display the I.D. plug identity upon power-up.

4. Install correct I.D. plug as needed.

Form O-MAPSIII&IV Cabinets A/B/C, P/N 257004R8, Page 39

Page 40

INDEX

Air Proving Switch 20

Ball Valve and Actuator in Gas

Control Option AG70 28 Bearings 7 Belts 7 Braze 15 Burner 21 Burner Assembly and Gas Train

23 Burner Maintenance 22

Burner Orices 23

Burner Removal Instructions 22

Charge the System 16 Coil Maintenance 8 Combustion Air Proving Switch 30 Compressor 12 Mount the Replacement

Compressor 14 Compressor Handling 13 Compressor Maintenance 11 Compressor Oil Charge 14 Compressor Replacement 13 Compressors by Circuit 11 Compressor Staging 11 Condenser Fans 8 Condensing Coil Cleaning 8 Control Locations 5 Control Locations (Heat Section)

25 Crankcase Heater 12. 16 Cross-Reference 6 Curb duct furnace 22

Damper Motor 20 Dampers and Damper Controls 20 Digital Controller 12 Digital Controller and Sensors 20 Digital

Controller LED’s 33 Variable Frequency Drive 20 Drive Components 7 Duct furnace 22

Check the Electrical System 16 Electric Heating Elements 31 Electric Heat Section

Maintenance 30 Energy Recovery Module 31 Evacuate the Circuit 15 Evaporator Coil Cleaning 9

Condenser Fan 8 Filter Driers 14 Filters 6 Filters in an Optional Energy

Recovery Module 7 Flame Sensor 23 Furnace Operation LED Display

Gas Heat Section Maintenance

21 Gas Manifold Pressure Switch

29 Gas Pressure Safety Switches

29 Gas Train for Modulating Control

(Option AG70) 26. 27 Gas Valves 26

HAZARD INTENSITY LEVELS

3 Heat Exchanger 21 Heat Exchanger Maintenance

22 Outside Air Hood 6 Hot Gas Bypass Valve 21

I/Q System Controller 20 ID Plug 36 Deep Modulation (Option AG70)

Ignition Board 36 Ignition Control Module (Deep

Modulation Board) 25 Ignition System for Modulating

Furnace with Gas Control

Option AG70 25 Ignitor 23

Check System for Leaks 15 Limit Control 30

Maintenance Requirements 3 Maintenance Schedule 4 Manifold Pressures for Gas

Modulation System 28 Model 2 Model JHUP 22 Modulating Gas Control Sequence

of Operation 26 Modulating Reheat 21 Modulating System Gas Valve

(Ball Valve and Actuator)

Alignment 28 Modulating Valve 27 Adjust gas modulation 28 Motor and Blower 8

Outside Air Hood 7

R410-A Refrigerant Charge for

MAPS®III Models 16 R410-A Refrigerant Charge for

MAPS®IV Models 17 RCB 6 RCC 6 RDB 6 RDC 6 RDCB 6 RDCC 6 RDDB 6 RDDC 6 RECB 6 RECC 6 REDB 6 REDC 6 REFERENCES 40 Refrigerant Pressure and

Temperatures 9

Setscrews 7 Cabinet C Sizes 6 Spark Board 25 Spark Gap 23

Motor Starter 20 SUBCOOLING 9 Subcooling 18 Recommended subcooling 9 SUPERHEAT 10 Recommended superheat 10 Superheat 18 Dirty Filter Switch 6 System Startup 17

Temperature/Pressure Conversion

Chart 10 Thermal Expansion Valves 19 Compressor Digital Controller

Troubleshooting 33 Troubleshooting - Electric Heat

Section, Models RECB and

REDB 34 Troubleshooting Gas Heat Section

36 Troubleshooting - Gas Heat

Section in Models RDCB and

RDDB 35 Troubleshooting - Modulating

Control 36 Troubleshooting - Refrigeration (All

Models) 32 Troubleshooting Gas Heat Section

Dual Single-Stage Operating Gas

Valve 27 Venter Maintenance 21 Venter Motor and Wheel 24 Venter Wheel Position 24 Voltage Imbalance 17 Voltage Phasing 17 Voltage Protection 21

REFERENCES: The Installation Manual, Control Instructions, this Operation/Maintenance Manual,

and applicable supplier instructions are shipped with the unit. The literature listed below is currently also available at www.ReznorHVAC.com.

• Installation Manual, Form I-MAPSIII&IV, applies to Cabinets A, B, C, & D

• Control Instructions, Form CP-MAPS D15/16/17/18

• Replacement Parts, Form P-MAPSIII&IV

Record installation information on the back

of the installation manual, Form I-MAPSIII&IV.

Keep all booklets for future reference.

www.ReznorHVAC.com; (800) 695-1901



Form O-MAPSIII&IV Cabinets A/B/C, Page 40

least the United States. All other trademarks are the property of their respective owners.

05/14 (Serial No. Date Code BNE) Form O-MAPSIII&IV Cabinet A/B/C (Version B.3)

Reznor RCB060 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual