Service Manual

ManualsBrandsAirQuest ManualsCooling & Air Quality4 Ton Multi-Positional Air Handler

496 08 8001 02 7/31/2015

Specifications subject to change without notice.

FEM4, FCM4, FSA4, FEA4, FSM4, FSU4, FXM4, FVM4, FMA4,

WAH, WAP, WAM, WAX, REM4

SERVICE AND MAINTENANCE INSTRUCTIONS

VERTICAL/HORIZONTAL/MULTI−POSITION FAN COIL UNITS

NOTE: Read the entire instruction manual before starting the

installation.

TABLE OF CONTENTS

PAGE

SAFETY CONSIDERATIONS 1......................

INTRODUCTION 1.................................

FAN COIL DESCRIPTION AND

TROUBLESHOOTING 2............................

FSM4, FSU4, FSA4 2...............................

FEM4P, FEM4X, FEA4X, FXM4, WAHA, WAPM, WAPT,

WAPL, WAHM, WAHT, WAHL, WAXM, WAXT, WAXL,

REM4P, REM4X 5.................................

FVM4 6...........................................

FCM4 12..........................................

FMA4P, WAMA 17..................................

FMA4X, WAXA 17..................................

ELECTRIC HEATER FUNCTION AND

TROUBLESHOOTING 22...........................

FEM4, FCM4, FSA4, FEA4, FXM4, FVM4, WAPM,

WAPT, WAPL, WAHM, WAHT, WAHL, WAXM, WAXT,

WAXL, REM4 22..................................

FMA4, WAMA, WAXA 22............................

CARE AND MAINTENANCE 23......................

FEM4, FCM4, FXM4, FVM4, WAP, WAH,

WAX, REM4 23....................................

FSA4, FEA4, FMA4, WAMA, WAXA 24................

REFRIGERANT FLOW−CONTROL DEVICES 25.......

THERMOSTATIC EXPANSION VALVES (TXV) 25......

PISTON BODY CLEANING AND REPLACEMENT 26...

COIL & CONDENSATE PAN REMOVAL AND

REPLACEMENT 27................................

R−410A QUICK REFERENCE GUIDE 30..............

SAFETY CONSIDERATIONS

Improper installation, adjustment, alteration, service,

maintenance, or use can cause explosion, fire, electrical

shock, or other conditions which may cause death, personal

injury or property damage. Consult a qualified installer, service

agency, or your distributor or branch for information or

assistance. The qualified installer or agency must use

factory−authorized kits or accessories when modifying this

product. Refer to the individual instructions packaged with kits

or accessories when installing.

Follow all safety codes. Wear safety glasses, protective

clothing and work gloves. Have a fire extinguisher available.

Read these instructions thoroughly and follow all warnings or

cautions included in literature and attached to the unit. Consult

local building codes and the current editions of the National

Electrical Code (NEC) NFPA 70.

In Canada, refer to the current editions of the Canadian

Electrical Code CSA C22.1.

Recognize safety information. This is the safety−alert symbol

. When you see this symbol on the unit and in instruction

manuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING, and

CAUTION. These words are used with the safety−alert

symbol. DANGER identifies the most serious hazards which

will result in severe personal injury or death. WARNING

signifies hazards which could result in personal injury or

death. CAUTION is used to identify unsafe practices which

may result in minor personal injury or product and property

damage. NOTE is used to highlight suggestions which will

result in enhanced installation, reliability, or operation.

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this caution may result in equipment

damage, improper operation or personal injury.

When coils are pressurized with nitrogen, open the

suction port first to release the nitrogen. Mesh screens

may dislodge if the liquid line is opened first.

CAUTION

UNIT OPERATION AND SAFERTY HAZARD

Failure to follow this warning could result in personal

injury or death.

R−410A systems operate at higher pressures than R−22

systems. Do not use R−22 service equipment or

components on R−410 equipment. Ensure service

equipment is rated for R−410A.

WARNING

INTRODUCTION

These fan coil units are designed for flexibility in a variety of

applications that meet upflow, horizontal, or downflow

requirements. Units are available in 1−1/2 through 5 ton

nominal cooling capacities. Factory−authorized, field−installed

electric heater packages are available in 5kW @ 240Vac

through 30kW @ 240Vac single phase selections and

3−phase selections..

ELECTRICAL OPERATION HAZARD

Failure to follow this warning could result in personal injury

or death.

Before installing or servicing unit, always turn off all power

to unit. There may be more than one disconnect switch.

Turn off accessory heater power if applicable. Lock out

and tag switch with a suitable warning label.

WARNING

Summary of content (30 pages)

PAGE 1
SERVICE AND MAINTENANCE INSTRUCTIONS VERTICAL/HORIZONTAL/MULTI−POSITION FAN COIL UNITS FEM4, FCM4, FSA4, FEA4, FSM4, FSU4, FXM4, FVM4, FMA4, WAH, WAP, WAM, WAX, REM4 NOTE: Read the entire instruction manual before starting the installation. TABLE OF CONTENTS PAGE SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . 1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 FAN COIL DESCRIPTION AND TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PAGE 2
SERVICE AND MAINTENANCE FAN COILS FAN COIL DESCRIPTION AND TROUBLESHOOTING The PSC motor is two or three speed direct drive. High−speed lead is black, low−speed lead is red, and common lead is yellow. Be sure proper blower speed has been selected.. The motor is turned on through two different routes. The first occurs when thermostat calls for the fan in cooling, heat pump, or fan−only mode. A 24−Vac signal is sent to relay, causing relay to close its normally open contacts, turning fan on.
PAGE 3
SERVICE AND MAINTENANCE FAN COILS sent to relay. This causes the relay to close its normally−open contacts, turning on fan. When thermostat no longer calls for the fan, the signal sent to relay is turned off and relay opens causing fan to turn off after a 90−second fan−off delay. b. Sequencer/Electric Heat Relay Interlock The fan will also operate whenever there is a call for electric heat, even if fan relay is not energized.
PAGE 4
SERVICE AND MAINTENANCE FAN COILS IF TRACES ARE OVERHEATED ON BACK OF PCB: Usually whenever a trace is blown on PCB, it means either there has been a high−voltage short or high voltage has been applied to low−voltage circuit. This can be prevented by making sure PCB is wired correctly before PCB has power applied to it. C. If Transformer Fuse Keeps Blowing: When low−voltage fuse blows, it means transformer would have blown if fuse had not been in circuit to protect it.
PAGE 5
SERVICE AND MAINTENANCE FAN COILS FEM4P, FEM4X, FEA4X, FXM4, WAHA, WAPM, WAPT, WAPL, WAHM, WAHT, WAHL, WAXM, WAXT, WAXL, REM4P, REM4X MULTI−SPEED ECM FAN MOTOR Low 90 sec off delay Tap 2 Medium 90 sec off delay Tap 3 High 90 sec off delay Tap 4 Electric heat † 0 sec off delay Tap 5 Max ‡ 0 sec off delay † electric heat airflow is same CFM as Tap 3, except 0 sec off delay ‡ high static applications, see airflow tables for max airflow Figure 3 − Motor Speed Selection TWO MOTOR STYLES 1 2 3
PAGE 6
SERVICE AND MAINTENANCE FAN COILS Figure 4 − FVM4 motor/ECM 5.0 Motor NAMEPLATE LABEL A13028 FVM4 Constant Air Flow Unlike fan coils using induction motors where static pressure affects airflow, these fan coils are constant airflow units. The blower delivers requested airflow regardless of static pressure. Consult fan coil Specification Sheet for static pressure limits. The ECM 5.0 is pre−programmed and contains airflow tables for all modes of operation.
PAGE 7
SERVICE AND MAINTENANCE FAN COILS Fuse Data: 5−amp automotive−type ATC/ATO (tan) at 32Vac, 200 percent current opening time of five seconds maximum. Electrical Connections Twenty−one 0.110−in pin terminals are used to provide programming selections for operating modes of ECM 5.0. The 6 selection modes are listed below. For additional information, refer to Easy Select Configuration Taps section.
PAGE 8
SERVICE AND MAINTENANCE FAN COILS Figure 6 − Easy Select Board Schematic SYSTEM DIAGRAM HEATER/MOTOR SEC1 SEC2 1/4" 1/4" 12 11 10 9 8 7 6 5 4 3 2 1 5 AMP AUX1 1/4" HUM1 1/4" AUX2 1/4" HUM2 1/4" GRY 1/4" DH J1 R W1 J2 W2 Y1 Y/Y2 DIODE LOGIC G O C AUX HEAT KW/CFM AC/HP SIZE SYSTEM AC/HP CFM TYPE ADJUST ON/OFF DELAY CONTINUOUS FAN A96431 Type Connection Heater Connection Table 2 – FVM4X Connections and Connectors Type Connector Pin No.
PAGE 9
SERVICE AND MAINTENANCE FAN COILS EASY SELECT CONFIGURATION TAPS The Easy Select taps are used by installer to configure system. The ECM 5.0 uses selected taps to modify its operation to a pre−programmed table of airflows. Airflows are based on system size and mode of operation and those airflows are modified in response to other inputs such as the need for de−humidification. (See Figure 5.) The FVM4 Fan Coils must be configured to operate properly with system components with which it is installed.
PAGE 10
SERVICE AND MAINTENANCE FAN COILS which initiates Superdehumidification and reduces the airflow to 50 percent of cooling. HEATING The base heat pump only heating airflow is determined by the SYSTEM TYPE selection on the Easy Select Board. If HP−EFFICIENCY is selected, the airflow is the same as Cooling. IF HP−COMFORT is selected, the airflow is 315 CFM per ton. The airflow will adjust up if necessary when auxiliary heating is required.
PAGE 11
SERVICE AND MAINTENANCE FAN COILS Use following procedure to check low voltage signals: The ECM motor in these fan coils receive low voltage signals from the Easy Select Board through the wiring harness assembly. The combination of pins energized at the motor determines the speed the motor will run. The procedure below isolates the fan coil from all external devices such as a thermostat, condensing unit, humidifier or electronic air cleaner.
PAGE 12
SERVICE AND MAINTENANCE FAN COILS Figure 7 − Humidistat Wiring for De−Humidify Mode EASY SELECT BOARD TERMINAL BLOCK J1 DH HUMIDISTAT REMOVE JUMPER R A95316 FCM4 Model FCM4 fan coil is designed to be installed with the Observert communicating wall control. The FCM4 fan coil will provide airflow at a rate commanded by the Observer wall control. The nominal airflow/ton rate is 350 CFM/ton. The Observer wall control will modify the commanded airflow under certain operating modes.
PAGE 13
SERVICE AND MAINTENANCE FAN COILS NOTE: Shorting or mis−wiring low voltage system wiring will not cause damage to fan coil control or Observer wall control but may cause low voltage fuse to open. C. ECM Motor Troubleshooting The ECM motor used in this product consists of two parts: the control module and the motor winding section. Do not assume motor or module is defective if it will not start.
PAGE 14
SERVICE AND MAINTENANCE FAN COILS priority, highest to lowest. Though multiple faults can exist at any time, only the highest priority code will be displayed on STATUS LED. Clearing the indicated fault when multiple faults exist will cause the next highest priority Status Code to be flashed. All existing faults, as well as a fault history, can be viewed at Observer wall control. STATUS CODE 45, CONTROL BOARD TEST FAULT: Fan coil control has failed internal start−up tests and must be replaced.
PAGE 15
SERVICE AND MAINTENANCE FAN COILS Table 5 – FCM4 self−identifying resistor values Heater Size kW No heater 9 15 20 24 30 Resistor Ohms Nominal Open 11k 18k 24k 33k 39k STATUS CODE 36, HEATER OUTPUT NOT SENSED WHEN ENERGIZED: Fan coil control is provided with circuitry to detect presence of a 24−Vac signal on Electric Heater stage 1 and stage 2 outputs.
PAGE 16
SERVICE AND MAINTENANCE FAN COILS components to control heating or cooling system for optimum comfort. Figure 9 − FCM4 Circuit Board LED Locations DX+DXï C R O Y CLS C W G R COMM STATUS SECï1 COM HUM OPN HEATER 16 SECï2 HPT Troubleshooting the FCM4 Fan Coil Circuit Board: The circuit board Fan Coil part number 1184554 Primary test that should be performed: Motor Line Voltage Check 1. Turn off power (240V). 2. Remove Plug 3 from ECM motor 3. Turn on power. 4.
PAGE 17
SERVICE AND MAINTENANCE FAN COILS FMA4P, WAMA, FMA4X, WAXA ! WARNING ELECTRICAL OPERATION HAZARD Failure to follow this warning could result in personal injury or death. Before installation or servicing system, always turn off main power to system. There may be more than one disconnect switch. Turn off accessory heater power if applicable. Lock out and tag switch with a suitable warning label. FAN MOTOR FMA4P, WAMA The FMA4P and WAMA motor is three−speed ECM direct drive.
PAGE 18
SERVICE AND MAINTENANCE FAN COILS Figure 12 − 18 & 24 PCB D. Fan Relay Later EHK2 heater kits include sequencers instead of relays. Relay coil is 24−V. Check for proper control voltage. Replace relay if faulty. CLEANING OR REPLACING REFRIGERANT FLOW−CONTROL DEVICE FMA4P, WAMA The FMA4P and WAMA piston can be removed and cleaned if believed to be plugged. This unit’s piston is unique and replacements are available from FAST.
PAGE 19
SERVICE AND MAINTENANCE FAN COILS Should temperature continue to fall, R−W circuit is made through second−stage room thermostat bulb. Circuit R−W energizes a sequencer bringing on supplemental electric heat. When thermostat is satisfied, its contacts open de−energizing contactor and sequencer. All heaters should stop. The indoor fan motor will stop after 90−100 seconds on the FMA4P and 30 or 90 seconds on the FMA4X.
PAGE 20
SERVICE AND MAINTENANCE FAN COILS Figure 16 − FMA4, WAMA, WAXA (sizes 18 & 24) Expanded View− Evaporator Parts & Drain Pan (FMA4X & WAXA use TXV, not shown) A13137B NOTE: Time Delay PCB replaced Time delay relay in newer production models. Figure 17 − FMA4, WAMA, WAXA (sizes 30 & 36) Expanded View− Case A13138B 20 Specifications subject to change without notice.
PAGE 21
SERVICE AND MAINTENANCE FAN COILS Figure 18 − FMA4, WAMA, WAXA (sizes 30 & 36) Expanded View− Duct Components, Blower & Electrical Parts A13139 NOTE: Time Delay PCB replaced Time delay relay in newer production models after V1515 Figure 19 − FMA4, WAMA, WAXA (sizes 30 & 36) Expanded View− Evaporator Parts & Drain Pan A13140 496 08 8001 02 Specifications subject to change without notice.
PAGE 22
SERVICE AND MAINTENANCE FAN COILS ELECTRIC HEATER FUNCTION AND TROUBLESHOOTING FEM4, FCM4, FSA4, FEA4, FXM4, FVM4, WAPM, WAPT, WAPL, WAHM, WAHT, WAHL, WAXM, WAXT, WAXL, REM4 This section describes EHK and EHC series electric heaters by examining the functional operation of these heaters. DESCRIPTION OF ELECTRIC HEATER COMPONENTS A. Limit Switch The limit switch is a temperature sensitive control whose function is to prevent system from overheating in abnormal conditions.
PAGE 23
SERVICE AND MAINTENANCE FAN COILS Because this is a thermally−activated device, ambient conditions affect the ON/OFF cycle. Higher ambient temperature means shorter ON times and longer OFF times. Application of these devices is such that the first switch ON not only turns on first heater element, but also ensures that indoor fan is energized, because first ON is last OFF. This ensures fan remains ON until the last heater de-energizes. C.
PAGE 24
SERVICE AND MAINTENANCE FAN COILS 6. Remove the three bolts holding motor mount to blower housing and slide motor and mount out of housing. Further disassembly should not be necessary as adequate clearance is available. 7. Remove blower wheel from housing by removing cutoff plate from blower housing outlet. Note wheel orientation and cutoff location for reassembly. The blower motor and wheel may be cleaned by using a vacuum with a soft brush attachment. 8.
PAGE 25
SERVICE AND MAINTENANCE FAN COILS vanes. Do not drop or bend wheel as balance will be affected. To reassemble unit, proceed as follows: 1. Place motor with mount attached on flat, horizontal surface with shaft up. 2. Set inlet ring on top of motor mount grommets. Center inlet ring flush on all three grommets. 3. Slide blower wheel onto motor shaft with setscrew upward and aligned with shaft flat portion. Vertically position wheel along shaft to position marked during disassembly.
PAGE 26
SERVICE AND MAINTENANCE FAN COILS equalizer tube to underside of diaphragm, with which the pin carrier spring pressure closes valve. The refrigerant flow is effectively stabilized to load demand with negligible change in superheat. ALUMINUM COIL UNIT TXV’s The distributor used on the all−aluminum coils is also made of aluminum. The TXV connection to the distributor is accomplished with a 3/4−in. Chatleff nut.
PAGE 27
SERVICE AND MAINTENANCE FAN COILS copper equalizer so that it doesn’t touch the aluminum components. CAUTION ! UNIT DAMAGE HAZARD Figure 23 − TXV Thread (Sealer) Location Failure to follow this caution could result in equipment damage. Washer Use a backup wrench and do not over tighten, as deformation of the piston body will occur, causing the piston to lodge in a partially open or closed position.
PAGE 28
SERVICE AND MAINTENANCE FAN COILS m. Attach the TXV bulb onto the suction line and insulate. n. Insulate the entire TXV body and outlet tubing to prevent sweating. 2. Turn off electrical supply to indoor unit. 3. Disconnect condensate drain line. ! Old all−aluminum coils with TXV When replacing a previous all−aluminum coil that contains a TXV, the old TXV can be reused and mounted inside the cabinet. a.
PAGE 29
SERVICE AND MAINTENANCE FAN COILS g. Recover any remaining refrigerant. NOTE: All condenser coils hold only a factory−supplied amount of refrigerant. Excess refrigerant, such as in long−line applications, may cause compressor internal pressure relief valve to open (indicated by sudden rise in vapor pressure) before refrigerant is recovered. If this occurs, turn off electrical supply to outdoor unit immediately, front seat (close) vapor service valve, and recover any remaining refrigerant. 2.
PAGE 30
SERVICE AND MAINTENANCE FAN COILS R−410A QUICK REFERENCE GUIDE  R−410A refrigerant operates at 50% − 70% higher pressures than R−22. Be sure that servicing equipment and replacement components are designed to operate with R−410A.  R−410A refrigerant cylinders are rose colored.  Recovery cylinder service pressure rating must be 400 psig, DOT 4BA400 or DOT BW400.  R−410A systems should be charged with liquid refrigerant. Use a commercial type metering device in the manifold hose.