Carrier 48EZ-A Troubleshooting Guide-Heating, Troubleshooting Guide-LED Error Codes

Page 36

48EZ -- A

Table 12 – Troubleshooting Guide–Heating

SYMPTOM

CAUSE

 

REMEDY

 

 

 

 

Water in gas line

Drain. Install drip leg.

 

No power to furnace

Check power supply fuses, wiring or circuit breaker.

 

 

Check transformer.

 

No 24--v power supply to control circuit

NOTE: Some transformers have internal over--current protection

 

 

that requires a cool--down period to reset.

Burners will not ignite

 

 

Mis--wired or loose connections

Check all wiring and wire nut connections

 

Misaligned spark electrodes

Check flame ignition and sense electrode positioning.

 

Adjust as necessary.

 

 

 

 

 

 

 

 

1.

Check gas line for air. Purge as necessary. NOTE: After purging

 

No gas at main burners

gas line of air, wait at least 5 minutes for any gas to dissipate be-

 

fore attempting to light unit.

 

 

 

 

2.

Check gas valve.

 

 

 

 

Dirty air filter

Clean or replace filter as necessary

 

Gas input to furnace too low

Check gas pressure at manifold match with that on unit nameplate

Inadequate heating

Unit undersized for application

Replace with proper unit or add additional unit

Restricted airflow

Clean or replace filter. Remove any restriction.

 

 

Limit switch cycles main burners

Check rotation of blower, temperature rise of unit. Adjust as neces-

 

sary.

 

 

 

 

 

 

 

 

1.

Tighten all screws around burner compartment

 

 

2.

Cracked heat exchanger. Replace.

 

Incomplete combustion results in: Aldehyde odors,

3.

Unit over--fired. Reduce input (change orifices or adjust gas line

Poor flame characteristics

or manifold pressure).

carbon monoxide, sooting flame, floating flame

 

4.

Check burner alignment.

 

 

 

 

5.

Inspect heat exchanger for blockage. Clean as necessary.

 

 

 

 

Table 13 – Troubleshooting Guide–LED Error Codes

SYMPTOM

CAUSE

REMEDY

 

 

 

 

No Power or Hardware fail-

 

Check 5--amp fuse son IGC*, power to unit, 24--v circuit breaker,

Loss of power to control module (IGC)*.

and transformer. Units without a 24--v circuit breaker have an

ure

 

 

internal overload in the 24--v transformer. If the overload trips,

(LED OFF)

 

 

 

 

allow 10 minutes for automatic reset.

 

 

 

 

 

 

 

Limit switch faults

 

Check the operation of the indoor (evaporator) fan motor. Ensure

High temperature limit switch is open.

that the supply--air temperature rise is in accordance with the

(LED 2 flashes)

 

range on the unit nameplate. Clean or replace filters.

 

 

 

 

 

 

Flame sense fault

The IGC* sensed flame that should not be present.

Reset unit. If problem persists, replace control board.

(LED 3 flashes)

 

 

 

 

 

4 consecutive limit switch

 

Check the operation of the indoor (evaporator) fan motor and that

faults

 

Inadequate airflow to unit.

supply--air temperature rise agrees with range on unit nameplate

(LED 4 flashes)

 

information.

 

 

 

 

Ignition lockout

 

Check ignitor and flame sensor electrode spacing, gaps, etc.

Unit unsuccessfully attempted ignition for 15 minutes.

Ensure that fame sense and ignition wires are properly terminated.

(LED 5 flashes)

 

Verify that unit is obtaining proper amount of gas.

 

 

 

 

 

 

 

 

 

 

Verify wiring connections to pressure switch and inducer motor.

Pressure Switch Fault

 

Verify pressure switch hose is tightly connected to both inducer

Open pressure switch.

housing and pressure switch. Verify inducer wheel is properly

(LED 6 flashes)

 

attached to inducer motor shaft. Verify inducer motor shaft is turn-

 

 

 

 

 

 

ing.

 

 

 

 

 

 

 

Rollout switch will automatically reset, but IGC* will continue to

Rollout switch fault

Rollout switch has opened.

lockout unit. Check gas valve operation. Ensure that induced--draft

(LED 7 flashes)

blower wheel is properly secured to motor shaft. Inspect heat

 

 

 

 

exchanger. Reset unit at unit disconnect.

 

 

 

Internal control fault

Microprocessor has sensed an error in the software

If error code is not cleared by resetting unit power, replace the

(LED 8 flashes)

or hardware.

IGC*.

Temporary 1 hr auto reset

Electrical interference impeding IGC software

Reset 24--v. to control board or turn thermostat off, then on again.

(LED 9 flashes)

Fault will automatically reset itself in one (1) hour.

 

*WARNING

: If the IGC must be replaced, be sure to ground yourself to dissipate any electrical charge that my be present before handling new control

board. The IGC is sensitive to static electricity and my be damaged if the necessary precautions are not taken. IMPORTANT: Refer to Table 11---Troubleshooting Guide---Heating for additional troubleshooting analysis.

LEGEND

IGC—Integrated Gas Unit Controller

LED—Light---Emitting Diode

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Contents Table of Contents Safety ConsiderationsReceiving and Installation IntroductionCheck Equipment Provide Unit Support48EZ-A24-36 Unit Dimensions 48EZ-A42-60 Unit Dimensions Small Curb Rig and Place Unit Provide ClearancesPersonal Injury or Property Damage HazardInstall Flue Hood Install Gas PipingConnect Condensate Drain InspectionFire or Explosion Hazard Sediment TrapPhysical Data Unit 48EZ-A Unit Size 48EZPhysical Data Unit 48EZ-A Cont’d Maximum Gas Flow CapacityHeating Inputs Install Duct Connections Configuring Units for Downflow Vertical DischargeAlternate Method Unit Component Damage HazardSupply Duct Panels Install Electrical Connections Special Procedures for 208-V OperationHigh-Voltage Connections Control Voltage ConnectionsBalance Point Setting-Thermidistat or Hybrid Thermostat PRE-START-UPTransformer Protection FIRE, EXPLOSION, Electrical Shock HazardStart-up Heating and Make Adjust- ments START-UPCheck for Refrigerant Leaks Unit Sequence of OperationAdjust Gas Input Check Heating ControlCheck Gas Input Unit Damage HazardAirflow and Temperature Rise Limit SwitchesRollout Switch Check Burner FlameStart-up Cooling and Make Adjust- ments Checking and Adjusting Refrigerant ChargeIndoor Airflow and Airflow Adjustments Checking Cooling Control OperationTwo Cooling Fan Speeds Set-up Dehumidification feature used Gas Heating Fan Speed Set-upContinuous Fan Operation Color Coding for Indoor Fan Motor LeadsFilter Pressure Drop Table IN. W.C 48EZ-A Wet Coil Pressure Drop IN. W.C741 638 547 415 Heating Low Blue 1234 1168 1093 1021 961 894 825 759 687 Heating Low Blue 1736 1695 1642 1601 1553 1512 1465 1427 1381 65oF Heating 1927 1893 1858 1824 1791 1759 1720 1689 1640 65oF Heating 48EZ a 208/230-3-60 Wiring Diagram, Unit 48EZ-A Cooling Charging Table-Subcooling Maintenance Cleaning the Blower Motor and WheelAir Filter Indoor Blower and MotorLimit Switch Induced Draft combustion air Blower AssemblyBurner Ignition Main BurnersElectrical Controls and Wiring Outdoor FanRefrigerant Circuit Pressure Switches Loss of Charge SwitchGas Input Indoor AirflowHigh-Pressure Switch Copeland Scroll Compressor Puron RefrigerantExplosion Hazard Unit Operation and Safety Hazard Refrigerant SystemCompressor Oil Troubleshooting START-UP ChecklistPuronr R-410A Quick Reference Guide Troubleshooting Guide Cooling or Heat Pump Heating Mode Symptom Cause RemedyTroubleshooting Guide-Heating Troubleshooting Guide-LED Error CodesTemperatures Remove and Store in Job FilesPreliminary Information Model no III. START-UP Electrical Supply Voltage Compressor AmpsCatalog No 48EZ---06SI
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