Reznor YDHA060 Service Manual

CQS

Form O-Y (4-16)

Obsoletes Form O-Y (11-15)

Operation / Maintenance / Service

Applies to: Models YDHA, YDMA, and YDSA

Packaged Rooftop Equipment

Model YDHA High Outside Air (Conditioned Ventilation)

Model YDMA - Conditioned Makeup Air

R-410A

Refrigerant

Model YDSA - Space Conditioning

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-Y P/N 273647R5, Page 1

Table of Contents

1.0 General .......................................................2

2.0 Maintenance Requirements .....................2

2.1 Maintenance Schedule ...........................................3

2.2 Control Locations ....................................................4

2.3 Cabinet Size 1 or 2 by Model & Size Cross-Referenced

to Heat Section Size & Type ...........................5

3.0 Maintenance and Service Procedures -

Unit & Cooling Components ....................6

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

3.2 Supply Fan and Variable Frequency Drive .............8

3.3 Optional Dampers and Damper Actuator ................9

3.4 Condenser Fans ...................................................10

3.5 Coils and Related Cooling Components ...............10

3.6 Check Refrigerant Pressure and Temperatures

(subcooling and superheat) ...........................17

3.7 Compressor Operation, Maint, and Replacement 19

3.8 Other Controls.......................................................27

4.0 Maintenance/Service Procedures - Power

Exhaust and Energy Recovery ..............27

4.1 Power Exhaust, Option PE ...................................27

4.2 Energy Recovery Wheel,

Option EW .....................................................28

5.0 Maintenance/Service Procedures - Gas

Heat Section ............................................32

5.1 Gas Heat Controls ................................................32

5.2 Combustion Air and Venting .................................37

5.3 Vent Maintenance and Operation .........................40

5.4 Burner and Heat Exchanger .................................41

6.0 Maintenance/Service Procedures - Electric

Heat Section ............................................42

7.0 Troubleshooting ......................................43

7.1 Troubleshooting - Refrigeration ............................43

7.2 Troubleshooting Compressor Digital Controller ...45

7.3 Troubleshooting the Heat Section ........................46

INDEX .............................................................48

1.0 General

Denitions of Hazard

Intensity Levels used in this Manual

2.0 Maintenance Requirements

Form O-Y, PN 273647R5, Page 2

This booklet includes operation, maintenance, and service information for Model YDHA, Model YDMA, and Model YDSA. Before beginning any procedure, carefully review the information, paying particular attention to the warnings. Handling of refrig-

erant 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.

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.

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, shown on page 4 and follow the instructions in the paragraphs referenced below to maintain this equipment. Maintenance requirements apply to all Models and Sizes unless noted.

this manual should only be 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 on page 2.

If replacement parts are required, use only factory-authorized parts. For

information, contact your local distributor.

2.1 Maintenance Schedule

Monthly

□ Inspect all lters; clean or replace as needed. See Paragraph 3.1, page 6. □ Inspect the cooling coil condensate drain; clean as needed. For information, see

Paragraph 3.5, page 10.

Annually

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 cooling coil condensate drain pan. Clean the coil cabinet, clean the

drain pan, and ll the trap.

□ Inspect/clean condenser fans. See Paragraph 3.4, page 10. □ Inspect/clean all coils. See Paragraph 3.5, page 10. □ Check refrigerant temperatures and pressures (superheat and subcooling).

These checks are done when the unit is operating. See Paragraph 3.6, page 17.

□ Check compressor operation. See Paragraph 3.7, page 19.

Systems with the Optional energy recovery wheel: See Paragraph 4.0, page 27.

□ Inspect the wheel and clean as needed. □ Check wheel RPM and drive components. □ Check wheel seals.

Systems with the Optional gas heat section (beginning of the heating

season) - See Paragraph 5.0, page 32:

□ 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.

Systems with the Optional electric heat section (beginning of the heating season) - See Paragraph 6.0, page 42:

□ Check wiring connections. □ Check the heat section and elements for dust or lint accumulation. Clean as

needed.

Form O-Y P/N 273647R5, Page 3

2.0 Maintenance Requirements (cont'd)

2.2 Control Locations

FIGURE 1 Access Doors and High and Low Voltage Control Locations

Comp

Cond

Condenser

Section

HIGH VOLTAGE CONTROL PANEL

Contactors

Cond

Comp

Condenser Fans

Electrical / Control

Compartments

(See below.)

Optional Gas or

Electric Heat Section

Supply

Fan

Access

Inlet Air Hood

Coil and

Filter Access

Damper Access

Optional Wheel Access

Compressor

Optional

Low

Ambient

Controller

- ECM

Condenser

Fan

Optional

Low

Ambient

Controller

- Std

Condenser

Fan

Controllers (by circuit)

Capacitors

Transformers 75 VA

Opt

Fuse Blocks

Gas Heat Section Controls

Ignition controller and combustion air pressure switch are located on the side wall next to the gas manifold and burner. See FIGURE 23, page

32.

VFD

VFD Line Reactor

High Voltage Bus Bar

- Compressor & Condenser Contactors

- 3-Phase Supply Wire Connections

- Optional Phase Loss Monitor

- Optional Power Exhaust Contactor

- Optional Energy Wheel Contactor

- Optional Energy Wheel Preheat Contactor

LOW VOLTAGE PANEL

* Optional Dirty Filter

Pressure Switch (1 or 2)

Relays

Optional Exhaust Airflow Pressure Switch High Side Tubing - Yellow Low Side Tubing - Clear

Supply Air Pressure Switch High Side Tubing - Blue Low Side Tubing - Clear

Optional Pressure Sensor Transducer (tubing is field supplied)

* Dirty Filter Switch for

System Filters (BE18) High Side Tubing - Red Low Side Tubing - Clear

Dirty Filter Switch for Wheel Filters (BE28) High Side Tubing - Green Low Side Tubing - Clear

Form O-Y, PN 273647R5, Page 4

Thermostat Terminal Strip

Carel Controller

2.3 Cabinet Size 1 or 2 by Model & Size Cross-Referenced to Heat Section Size & Type

Model YDHA YDMA YDSA

Nominal Cooling Capacity (Tons)

Standard

Efciency

Gas Heat

Section

High

Efciency

Gas Heat

Section

Electric

Heat

Section

* Gas heat sections with dual furnaces.

Size 60 90 120 150 180 210 240 300 360 60 90 120 150 180 210 240 300 360 120 150 180 210

5 7.5 10 12.5 15 17.5 20 25 30 5 7.5 10 12.5 15 17.5 20 25 30 10 12.5 15 17.5

Opt

Code

H50 1 1 1 -- -- -- -- -- -- 1 -- -- -- -- -- -- -- -- -- -- -- -- H50 H75 1 1 1 1 2 -- -- -- -- 1 1 1 -- -- -- -- -- -- -- -- -- -- H75

H100 1 1 1 1 2 2 2 -- -- 1 1 1 1 -- -- -- -- -- 2 -- -- -- H100 H102* 1 1 1 1 2 2 2 -- -- 1 1 1 1 -- -- -- -- -- 2 -- -- -- H102* H125* 1 1 1 1 2 2 2 -- -- 1 1 1 1 2 -- -- -- -- 2 2 -- -- H125* H150* 1 1 1 1 2 2 2 -- -- 1 1 1 1 2 2 -- -- -- 2 2 3 -- H150* H175* 1 1 1 1 2 2 2 -- -- 1 1 1 1 2 2 2 -- -- 2 2 3 3 H175*

H200 -- 1 1 1 2 2 2 3 3 1 1 1 1 2 2 2 3 3 2 2 3 3 H200 H202* -- 1 1 1 2 2 2 3 3 1 1 1 1 2 2 2 3 3 2 2 3 3 H202*

H300 -- 1 1 1 2 2 2 3 3 -- 1 1 1 2 2 2 3 3 2 2 3 3 H300

H400 -- -- 1 1 2 2 2 3 3 -- -- 1 1 2 2 2 3 3 2 2 3 3 H400 H402* -- -- 1 1 2 2 2 3 3 -- -- 1 1 2 2 2 3 3 2 2 3 3 H402* H502* -- -- -- -- 2 2 2 3 3 -- -- -- -- 2 2 2 3 3 -- -- 3 3 H502* H602* -- -- -- -- 2 2 2 3 3 -- -- -- -- 2 2 2 3 3 -- -- --- 3 H602* H702* -- -- -- -H802* -- -- -- -- -- -- -- 3 3 -- -- -- -- -- -- -- 3 3 -- -- -- -- H802*

G150 1 1 1 1 2 2 2 -- -- 1 1 1 1 2 2 2 -- -- 2 2 3 3 G150

G225 1 1 1 1 2 2 2 3 3 1 1 1 1 2 2 2 3 3 2 2 3 3 G225

G300 -- 1 1 1 2 2 2 3 3 -- -- 1 1 2 2 2 3 3 2 2 3 3 G300 G302* -- 1 1 1 2 2 2 3 3 -- -- 1 1 2 2 2 3 3 2 2 3 3 G302* G372* -- -- -- -- 2 2 2 3 3 -- -- -- -- 2 2 2 3 3 -- 2 3 3 G372* G452* -- -- -- -- 2 2 2 3 3 -- -- -- -- 2 2 2 3 3 -- -- 3 3 G452* G525* -- -- -- -- -- -- -- 3 3 -- -- -- -- -- -- -- 3 3 -- -- -- -- G525* G602* -- -- -- -- -- -- -- 3 3 -- -- -- -- -- -- -- 3 3 -- -- -- -- G602*

E20 1 1 1 1 2 2 2 -- -- 1 1 1 1 2 2 2 -- -- 2 2 3 3 E20 E30 1 1 1 1 2 2 2 3 3 1 1 1 1 2 2 2 3 3 2 2 3 3 E30 E40 -- 1 1 1 2 2 2 3 3 -- 1 1 1 2 2 2 3 3 2 2 3 3 E40 E50 -- 1 1 1 2 2 2 3 3 -- 1 1 1 2 2 2 3 3 2 2 3 3 E50 E60 -- 1 1 1 2 2 2 3 3 -- 1 1 1 2 2 2 3 3 2 2 3 3 E60 E70 -- -- 1 1 2 2 2 3 3 -- -- 1 1 2 2 2 3 3 2 2 3 3 E70 E80 -- -- 1 1 2 2 2 3 3 -- -E90 -- -- 1 1 2 2 2 3 3 -- -- 1 1 2 2 2 3 3 2 2 3 3 E90

E120 -- -- -- -- 2 2 2 3 3 -- -- -- -- 2 2 2 3 3 -- -- 3 3 E120

-- -- -- 3 3 -- -- -- -- -- -- -- 3 3 -- -- -- -- H702*

1 1 2 2 2 3 3 2 2 3 3 E80

Opt

Code

Form O-Y P/N 273647R5, Page 5

3.0 Maintenance

Filter Clip P/N 284026

and Service Procedures Unit & Cooling Components

3.1 Filters

Systems with disposable lters require more frequent lter inspection. Exposure to humid makeup air can accelerate lter degradation. Replace lters when needed using the same type of lters as the original.

Supply Air Filters - The supply air lters are 4-inch pleated disposable lters. Replacement lters are listed in the table below. Do not use any other type of lters.

FIGURE 2 - Installing Replacement Supply Air Filters

Replacement Filters by Model Size and Cabinet Size

Cabinet Size Model(s) Model Sizes Qty Size P/N P/N

YDHA & YDMA

YDHA & YDMA 180, 210, 240 4 16 x 25 211128 256666

YDSA 120, 150 4 16 x 25 211128 256666

YDHA & YDMA 300 & 360

YDSA 180 & 210

060 1 16 x 25 211128 256666

090, 120, 150 2 20 x 24 222480 260828

4" Disposable

Pleated

4 25 x 29 235757 235758

MERV 8 MERV 13

To access supply air lters, open the cooling coil / lter door. Follow the instructions

that apply.

Cabinet Size 0

(see table above)

Instructions:

1) Slide filter clip left and remove.

2) Slide filters out.

3) Install new filters.

4) Replace filter clip.

Filter Clip, P/N 272222

Filter

Cabinet Size 2

(see table above)

Instructions:

1) Slide filter clip tab from the slot in the filter support. Rotate clip slightly and remove filter clip.

2) Slide filters out.

3) Install new filters.

4) Replace filter clip.

Filter

Filter Clip, P/N 272707

Filter

Form O-Y, PN 273647R5, Page 6

Cabinet Size 3

(see table above)

Instructions:

1) Slide filter clip tab from the slot in the filter support. Rotate the clip slightly and remove filter clip.

2) Slide filters out.

3) Install new filters.

4) Replace filter clip.

Filter

3.1 Filters (cont'd)

Energy Recovery Wheel Filters - The energy recovery wheel has two 1-inch lters

in both the supply and exhaust airstreams. Replacements are listed below. Size of lter is determined by CFM. Permanent lters may be washed and dried and re-used.

To access lters, open the wheel door. Slide the lters out of the lter racks. Do not operate the system without lters in place.

Filter Application by Cabinet & ER Wheel Sizes

Cabinet

Size

ER Wheel Size Model Model Size Qty Filter Size

30" dia 36" dia

36" dia

46" dia

36" dia 46" dia

52"dia

58"dia

YDHA & YDMA 060, 090, 120, 150

090, 120, 150

YDHA & YDMA 180, 210, 240 4 20 x 25 101610

YDSA 120, 150 4 20 x 25 101610

YDHA & YDMA 180, 210, 240 4 25 x25 119779

YDSA 120, 150 4 25 x 25 119779 YDSA 180, 210 YDSA 180, 210 4 16 x 20 101607

YDHA 300, 360 4 16 x 20 101607

YDHA & YDMA 300, 360 4 16 x 20 101607

4 16 x 16 104102 4 20 x 20 101608

4 20 X 25 101610

4 20 x 20 101608 2 16 x 25 101609 2 20 x 25 101610

1" Permanent

P/N

Dirty Filter Switch (Options BE18 or BE28)

Systems may be equipped with a dirty lter pressure switch (Option BE18) that will trigger an alarm when the resistance through the inlet air lters indicates that lter

replacement is required. Systems with an energy recovery wheel may be equipped

with two dirty lter pressure switches (Option BE28), one for the inlet air lters and one for the energy recovery wheel supply lters.

When performing maintenance, check the condition of the sensing tubes to be sure

that they are not blocked. Check the wiring connections. To set a new dirty lter

switch, see Installation Form I-Y, Paragraph 8.3. Replacement switch is P/N 105507.

FIGURE 3 - Removing and Installing Filters in the Outside Air Hood

Permanent Filters in the Outside Air Hood (Option AS16)

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 FIGURE 3, shown below. 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 listed below.

Instructions:

Front Cover

Filter

YSDA Models -- 120, 150 180, 210 YDHA, YDMA

Models

Filter No / Size /

(Qty)

060, 090, 120, 150 180, 210, 240 300, 360

Filter

1 2 3

101607

16x20x1 - (4)

1) Remove two screws, one on each end of the front cover. Remove the cover.

2) Slide filters out.

3) Clean and dry filters.

4) Return filters to hood and replace cover.

Cabinet Size

101610

20x25x1 - (4)

101609

16x25x1 - (8)

Form O-Y P/N 273647R5, Page 7

3.0 Maintenance and Service Procedures - Unit & Cooling Components (cont'd)

3.2 Supply Fan and Variable Frequency Drive

Supply fan in "slide out" position

Approx fan sled screw locations

Variable Frequency Drive

FIGURE 4 - VFD Display

Fan motors are permanently lubricated; lubrication is not required, During maintenance, remove any accumulation of dirt and grease. The fan CFM was

checked and balanced at startup. To recheck, follow the instructions in the installation manual, Form I-Y, Paragraph 10.3.

If service is required, the supply fan is mounted on a sled that will slide out of the cabinet.

Instructions for sliding out the supply fan:

1. Turn off the power and lock the disconnect switch.

2. Open the supply fan door and the cooling cabinet door.

3. The exible duct joining the supply fan to the cooling compartment is visible.

Locate the metal ange holding the duct to the cabinet. Remove the two screws from fan sled (locations shown in picture on the left) and the ange to free the duct

so that it can be slid out with the fan.

4. Open the electrical box on the fan. Mark and disconnect the wires.

5. Carefully slide the complete fan sled out of the cabinet.

6. When service is complete, slide the sled into the cabinet. Re-connect the wires

and re-attach the ange to hold the exible duct in place. If the pressure tube was

removed during service, be sure to re-attach it securely. Reinstall two screws into the fan sled.

Function: When the main controller calls for supply fan operation, a variable fre-

quency drive (VFD) responds to operate the motor. The VFD is located on the high voltage electrical panel (See FIGURE 1, page 4).

Control of the variable frequency drive module is dictated by the main controller, and depending on what was ordered, can function in response to temperature, CO

, or

pressure controls. !

Service: Remove any dirt or dust. Check the wire connections. If a VFD needs

to be replaced, use a factory-authorized replacement designed for the application.

1) LCD Display

4) UP

Variable Frequency Drive Model ACS550

Variable Frequency Drive Model ACS355

2) RESET / EXIT

6) LOC / REM

8) STOP

5) DOWN

Code Control Panel Display

1 LCD display -

Divided into 5 areas

2 RESET / EXIT Resets faults and exits to higher menus

3 MENU / ENTER Menu selection and saves value

4 UP Scrolls up through menu / list

5 DOWN Scrolls down through menu / list

6 LOC / REM - VFD controlled by main controller

7 DIR - Changes the direction of the motor

8 STOP - Stops the drive

9 START - Starts the drive

Upper left - Control location

Upper right - unit of the displayed value

Center - Parameters and signal values, menus and alarm codes

Lower left and center - Operation state

Lower right - Motor rotation

Increases value of parameters or reference values

Decreases value of parameters or reference values

3) MENU / ENTER

7) DIR

9) START

Form O-Y, PN 273647R5, Page 8

3.0 Maintenance and Service Procedures - Unit & Cooling (cont'd)

3.2 Supply Fan and Variable Frequency Drive (cont'd)

Air Proving Switch P/N 234712 Set Point 0.10 I.W.C.

Outside Air Humidity and Temperature Sensor

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

controller that the supply fan is operating. If equipped with power exhaust or an

energy recovery wheel, there is a second air proving switch that veries the exhaust

fan is operating. See location in FIGURE 1, page 4. Service: If a switch needs to be replaced, use a factory-authorized replacement

designed for the application.

Function: All systems have an outside air humidity and temperature sensor in the outside air inlet. The sensor is wired to the system controller in the electrical compartment.

Service: Check the wiring. If the sensor needs replaced, use a factory-authorized

replacement designed for the application.

FIGURE 5 - Outdoor Air Sensor, P/N 222754, is mounted in the outside air inlet (behind the hood)

3.3 Optional Dampers and Damper Actuator

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 Actuator (Options AR7, AR8, AR2D, AR2L, AR2Y)

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 Damper Actuator (Options AR25, AR2G, AR2H, AR2M)

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-Y.

FIGURE 6 - Damper Actuator is mounted on the damper frame and is accessible through the Damper Access Door (See FIGURE 1, page 4).

Form O-Y P/N 273647R5, Page 9

3.0 Maintenance and Service Procedures - Unit & Cooling (cont'd)

3.4 Condenser Fans

3.5 Coils and Related Cooling Components

Condenser Coil Cleaning Instructions

Depending on the model size, there are two or four condenser fans. Fan motors may

be either standard efciency or ECM speed control. If parts need to be replaced, use

only factory authorized replacement parts.

FIGURE 7 - Condenser Fans

Guard

Housing

Propeller Fan

Fan Support

Motor

Condenser Fan Section Assembly

The DX cooling system is equipped with copper nned coils. 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).

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

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

Evaporator Coil Cleaning Instructions:

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

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.

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

2. Open the cooling coil door.

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

Form O-Y, PN 273647R5, Page 10

3.5 Coils and Related Components (cont'd)

Condensate Drain Use and Maintenance

Thermostatic Expansion Valves

Thermostatic Expansion Valve

Seasonal Usage - At the beginning of the cooling season, inspect and clean the

entire cooling coil cabinet including the condensate drain pan. Thoroughly clean dirt, algae, grease, and other contaminants. Inspect condensate drain pan, trap, and pip-

ing; ll trap with water to ensure proper operation. During a wintertime shutdown of

the cooling system, it may be desirable to disconnect and remove all water from the trap and drain to prevent freeze damage. If local building codes permit, trap may be

lled with an antifreeze solution. Or, piping may be designed with freeze plugs or

other freeze protection methods (such as a heat tape).

Year Round Usage - Climates or applications with cooling requirements year round

require more frequent inspections of the cooling coil cabinet and condensate drains. Depending on climate, freeze protection of the trap may be required during noncooling days. 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 R-410A refrigerant and must be sized correctly for the application. All refrigerant ser-

vice should be performed by a service technician qualied in R-410A refrigerant. Replacement valve P/N's by Model, size, and circuit are listed in the table. Locations

are shown in FIGURES 8 through 14, shown on pages 11 through 14.

Thermostat Expansion (TXV) Valves by Circuit and P/N

Model / Size A B DH - Low Enthalpy DH - High Enthalpy

YDHA & YDMA 060 234987 -- 207303 --

YDHA 090 220556 -- -- 207303

YDMA 090 220556 -- 207303 --

YDHA & YDMA 120 234987 234987 -- 207303

YDSA 120 234960 234960 -- --

YDHA & YDMA 150 220555 220555 -- 207303

YDSA 150 220555 220555 -- --

YDHA & YDMA 180 220555 220555 207303 234960

YDSA 180 220555 220555 -- --

YDSA 210 220556 220555 -- --

YDHA & YDMA 210 220556 220556 207303 234960

YDHA & YDMA 240 220556 220556 207303 234960

YDHA & YDMA 300 261175 221175 234960 235729

YDHA & YDMA 360 220558 220558 234960 235729

Refrigerant Circuits - Standard Cooling without Optional Bypass Valve or Reheat

FIGURE 8 - Cooling Circuit - Models YDHA and YDMA

Circuit A-1&2

Model JDHA 062 and 092 (Cabinet 0)

Sizes 060 and 090

Evaporator

Circuit A-1

Coil with Single Circuit

Filter Drier

Condenser Coil

Circuit A-1

Solenoid

Valve

Modulating

View from Compressor and

Condenser Section Side

Compressor

Circuit A-2

Condenser Coil

Circuit A-2

Equalizer

Evaporator

Tube

TXV

Valve

View from Cooling Cabinet Door

(Evaporator Coil Side)

Form O-Y P/N 273647R5, Page 11

Coil

3.0 Maintenance and Service Procedures - Unit & Cooling (cont'd)

3.5 Coils and Related Components (cont'd)

FIGURE 9 - Cooling Circuits - Models YDHA and YDMA Sizes 120 and 150

Evaporator Coil

with intertwined

Circuits A & B

Circuit A

Circuit B

Circuit A

Condenser Coil

Circuit A

Solenoid Valve

Circuit B

Model JDHA 120 and 150 (Cabinet 1)

Condenser Coil

Circuit B

Valves

Circuit B

TXV

FIGURE 10 - Cooling Circuits - Model YDSA Sizes 120 and 150; Models YDHA and YDMA Sizes 180, 210, and 240

Circuit A

Evaporator

Coil with

intertwined

Circuits A & B

Circuit A

Filter Drier

Circuit A

Condenser Coil

Circuit A

Solenoid Valve

Filter Drier

Circuit B

Modulating

Compressor

(Circuit A)

View from Compressor and

Condenser Section

Circuit B

Modulating

Compressor

(Circuit A)

View from Compressor and

Condenser Section

Model JDHA 180, 210, and 240 (Cabinet 2)

Circuit B

Filter Drier

Compressor

(Circuit B)

Compressor

(Circuit B)

Condenser Coil

Circuit B

Equalizer

Tubes

View from Cooling Cabinet Door

Circuit B

View from Cooling Cabinet Door

(Evaporator Coil Side)

Circuit A

(Evaporator Coil Side)

Equalizer

Tube

Evaporator

Coil

Evaporator

Coil

TXV Valves

Equalizer Tube

Circuit A

FIGURE 11 - Cooling Circuits - Model YDSA Sizes 180 and 210

Form O-Y, PN 273647R5, Page 12

Circuit A

Evaporator Coil with Intertwined Circuits A & B

Circuit A

Condenser Coil

Circuit A

Filter Drier

Circuit B

Compressor (Circuit A)

Model YDSA 180 and 210 (Cabinet 3)

Condenser Coil

Circuit B

Compressor (Circuit B)

Filter Drier

View from Compressor and

Condenser Section

Equilizer Tube

Circuit B

TXV Valves

Circuit A

View from Cooling Cabinet Door

(Evaporator Coil Side)

Evaporator Coil

Filter Drier

FIGURE 12 - Cooling Circuits - Models YDHA and YDMA Sizes 300 and 360

Circuit B

Circuit A

Model JDHA 300 and 360 (Cabinet 3)

Condenser Coil

Circuit B

TXV Valves

Optional Modulating Reheat (High Enthalpy Option RPLE or Low Enthalpy Option RPHE)

Circuit A

Condenser Coil

Circuit A

Filter Drier

Compressor

(Circuit A)

Circuit B

Filter Drier

View from Compressor and

Condenser Section

Circuit B

Compressor

(Circuit B)

Equilizer Tube

Circuit B

Circuit A

Filter Drier

Evaporator Coil

View from Cooling Cabinet Door

(Evaporator Coil Side)

Function: Units equipped with optional reheat have a dedicated refrigerant system (DH circuit) that precools the incoming air then directly uses the condenser waste heat to reheat the air after it passes through the DX cooling coil. The reheat system precooling evaporator coil is upstream of the main evaporator coil and the reheat condenser coil is downstream. The upstream "precool" coil tempers outside air and lowers the wet bulb depression of the air entering the main evaporator coil. The heat removed at the precool coil is rejected to the downstream "reheat" coil.

Operation of the DH circuit is controlled by the digital controller in the electrical compartment. See FIGURE 1(shown on page 4) and Figures 13 and 14 (shown on pages 13 & 14). The digital controller interfaces with the system controller and provides protection and diagnostics for compressor operation.

Service: See Troubleshooting Chart in Paragraph 7.2 on page 45 for identication of

alarm codes. Use only factory-authorized replacement parts.

FIGURE 13 - Optional DH Circuit (Option RPLE Low Enthalpy Reheat Pump or Option RPHE Low Enthalpy Reheat Pump

Condenser Coil

Circuit A

Modulating

Compressor

(Optinal DH Circuit)

Coil

Solenoid Valve

View from Compressor and

Coil

Condenser Section

Circuit DH

Condenser Coil

Circuit B

Model JDHA 060, 090, 120, and 150 (Cabinet 1)

Model JDHA 180, 210, and 240 (Cabinet 2)

Equalizer

Tube

View from Cooling Cabinet Door

(Evaporator Coil Side)

TXV Valve

Filter Drier

Form O-Y P/N 273647R5, Page 13

3.0 Maintenance and Service Procedures - Unit & Cooling (cont'd)

3.5 Coils and Related Components (cont'd)

Optional Modulating Reheat (cont'd)

FIGURE 14 - Optional DH Circuit (Option RPLE High Enthalpy Reheat Pump or Option RPHE Low Enthalpy Reheat Pump

Model JDHA 300 & 360 (Cabinet 3)

Circuit A & B

Condenser Coil

Circuit A

Modulating Compressor

View from Compressor and

Condenser Section

Evaporator Coil with Intertwined Circuits A & B

Condenser Coil

Circuit B

TXV Valves

Filter Drier

Equilizer Tube

View from Cooling Cabinet Door

FIGURE 15 - Digital Controller for DH Circuit Compressor, P/N 266067

Compressor Digital

Modulating Operation

Optional Hot Gas Bypass Valve (Option AUC8)

Controller for

LED

Color

Power Light

COM

Alarm Light (Red LED) - See Paragraph 7.2 shown on page 45.

(Green LED)

Compressor Modulating Solenoid Valve Energized Light (Yellow LED)

VAC

Green Solid

Green Flashing Anti-short cycle timer is active

Yellow Solid

Red Not lit No abnormal operation alerts Red Flashing See Paragraph 7.2 (page 45).

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. Hot gas bypass is only on the

non-modulating compressor circuit (Circuit B). See FIGURE 16 on page 15. 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).

LED

State

Power (24VAC present at

power terminals)

Unloader (Solenoid valve

is energized; compressor

capacity is 0.)

Evaporator Coil

(Evaporator Coil Side)

Indicates

Hot Gas Bypass Valve

Form O-Y, PN 273647R5, Page 14

CAUTION: Touching the operating hot gas bypass valve can cause a burn. Use caution when checking and adjusting the valve. See Hazard Levels, page 2.

If a hot gas bypass valve needs to be replaced, use only a factory-authorized replacement for R-410A refrigerant. All refrigerant service should be done by a

qualied R-410A service technician.

FIGURE 16 - Cooling Circuit B with Optional Bypass Valve (Option AUC8)

Hot Gas Bypass Check Valve at the Evaporator Coil

Circuit B with Optional Hot Gas Bypass

Model JDHA 120 and 150 (Cabinet 1) with Option AUC8

Model JDHA 180, 210, and 240 (Cabinet 2) with Option AUC8

Model JDHA 300 and 360 (Cabinet 3) with Option AUC8

Modulating

Compressor

(Circuit A)

Low Ambient Control, Option BE8

Option BE Pressure Controller with Fan Option CUF3, P/N 261041

Shutoff Valve

Compressor

(Circuit B)

Condenser Coil

Circuit B

Equalizer

Tube

Hot Gas Bypass Valve

Shutoff Valve

Condenser

Coil - Circuit B

Condenser Coil

Circuit A

Hot Gas Bypass Valve

Compressor

(Optional Circuit DH)

View from Compressor and

Condenser Section

If equipped with low ambient control, cooling is allowed to operate with an outside air tempera-

ture as low as 35°F (1.7°C).

Low Ambient Control for standard condenser fans (Option BE8 with Fan Option CUF3)

The electronic head pressure control modulates condenser fan motor speed in low temperatures, varying the air volume through the condenser to regulate head pressure. This model’s dual sensor input allows for the control of one or two independent refrigerant circuits sharing the same fan motor(s). Only open, drip

proof, PSC or Shaded Pole motors are applicable for motor speed regulation. The Controller monitors the liquid line temperature(degrees of excessive sub-cooling)

which is directly proportional to the head pressure. Speed modulation begins at 80°F liquid line and proportionally reduces the fan to minimum speed once the liquid line temperature reaches 50°F. Motor is turned off at liquid temperatures below or equal to

50°F. At 53°F the fan restarts at full speed; then modulates to minimum speed. When

the liquid temperature is 50°F and below the condenser fan motor will cycle between minimum RPM and off to maintain proper condenser temperature (head pressure).

The above describes a 30ºF span (80ºF to 50ºF) function; a 25ºF span is also available. The 25ºF span is recommended for High Efciency systems; 30ºF span for typical systems. Variable condenser airow is modulated from full to minimum speed

over the selected span.

Temperature to Resistance Table

Use Temperature to Resistance table shown on right to verify proper sensor operation.

Form O-Y P/N 273647R5, Page 15

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