Bryant 551A operation manual EconoMi$er Troubleshooting, Problem Potential Cause Remedy

Page 34

Table 19 — EconoMi$er Troubleshooting

 

PROBLEM

POTENTIAL CAUSE

REMEDY

Damper Does Not

Indoor (Evaporator) Fan is

Check to ensure that 24 vac is present at Terminal C1 (Common Power)

Open

Off

on the IFC (Indoor [Evaporator] Fan Contactor) or that 24 vac is present at

 

 

 

the IFO (Indoor [Evaporator] Fan On) terminal. Check whether 24 vac is

 

 

 

present at PL6-1 (red wire) and/or PL6-3 (black wire). If 24 vac is

 

 

 

not present, check wiring (see unit label diagram).

 

 

 

Check proper thermostat connection to G on the connection board.

 

 

No Power to EconoMi$er

Check to ensure that 24 vac is present across Terminals 24 VAC and

 

 

Controller

24 V COM on the EconoMi$er control. If 24 vac is not present, check wiring

 

 

 

(see unit label diagram). If 24 vac is present, STATUS light should be on

 

 

 

constantly.

 

 

No Power to G Terminal

If IFM is on, check to ensure 24 vac is present on G Terminal of the

 

 

 

EconoMi$er controller. If 24 vac is not present, check wiring (see unit

 

 

 

label diagram).

 

 

Controller Fault

If STATUS light is flashing one flash, the EconoMi$er controller is

 

 

 

experiencing a fault condition. Cycle power to the controller. If condition

 

 

 

continues, replace the EconoMi$er controller.

 

 

Thermostat Fault

If STATUS light is flashing two flashes, the EconoMi$er controller senses that

 

 

 

the thermostat is wired incorrectly. Check wiring between the thermostat

 

 

 

and the connection board in the electrical panel. The fault condition is

 

 

 

caused by Y2 being energized before Y1.

 

 

Actuator Fault

Check the wiring between the EconoMi$er controller and the actuator.

 

 

 

Hold CONFIG button between 3 and 10 seconds to verify the

 

 

 

actuator’s operation. (This process takes 3 minutes to complete.)

EconoMi$er

Minimum Position Set

Verify that the MIN POS (%) is set greater than zero. Adjust MIN POS (%)

Operation Limited to

Incorrectly

to 100% to verify operation, and then set to correct setting.

Minimum Position

EconoMi$er Changeover

Set at correct value. See Table 6.

 

 

Set Point Set Too High or

 

 

 

Too Low

 

 

 

Discharge Air

If STATUS light is flashing 4 flashes, Discharge Air Thermistor is

 

 

Thermistor Faulty

faulty. Check wiring or replace sensor.

 

 

Outdoor Air Temperature

If STATUS light is flashing 5 flashes, Outdoor Air Temperature Sensor is

 

 

Sensor Faulty

faulty. Check wiring or replace sensor.

Damper Position

Supply Air Low Limit

The supply-air temperature is less than 45 F, causing the minimum

Less than Minimum

Strategy Controlling

position to be decreased. Refer to the Start-Up instructions. Verify correct

Position Set Point

 

setting of MIN POS (%). If correct, EconoMi$er is operating correctly.

Damper Does Not

CO2 Ventilation Strategy

If a CO2 sensor is being used, and the damper position is greater than

Return to Minimum

Controlling

minimum position, the ventilation control strategy is controlling. Refer to

Position

 

the Start-Up instructions. EconoMi$er is operating correctly.

Damper Does Not

Damper Travel is

Check to ensure the damper is not blocked.

Close on Power Loss

Restricted

 

 

LEGEND

 

 

IFM

Indoor Fan Motor

 

 

PL

Plug

 

 

Table 20 — Perfect Humidity™ Dehumidification Subcooler Service Analysis

PROBLEM

CAUSE

 

REMEDY

Subcooler will not energize

No power to subcooler

Check power source. Ensure all wire connections

 

control transformer.

are tight.

 

No power from subcooler control transformer

1.

Fuse open; check fuse. Ensure continuity of wiring.

 

to liquid line three way valve.

2.

Subcooler control low-pressure switch open.

 

 

 

Cycle unit off and allow low-pressure switch

 

 

 

to reset. Replace switch if it will not close.

 

 

3.

Transformer bad; check transformer.

 

Liquid line three-way valve

1.

Solenoid coil defective; replace.

 

will not operate.

2.

Solenoid valve stuck closed; replace.

Subcooler will not deenergize

Liquid Line three-way valve

Valve is stuck open; replace.

 

will not close.

 

 

Low system capacity

Low refrigerant charge or

1.

Check charge amount. See system charging

 

frosted coil.

 

section.

 

 

2.

Evaporator coil frosted; check and replace

 

 

 

subcooler control low pressure switch if necessary.

Copyright 2001 Bryant Heating & Cooling Systems

CATALOG NO. 5355-105

Image 34
Contents Installation Provide Unit Support ContentsSafety Considerations II. RIG and Place UnitRoof Curb Details 180 Unit Maximum Dimensions Shipping WeightFt-in 155 240Ft-in 155 1575 714 36.3 407 185 375 170 383 174 410 Unit STD Unit ECONOMI$ER Corner DIM a DIM B DIM C Weight551A 1039 1054 559 180 1650 748 36.3 375 170 449 204 452Base Unit Dimensions, 551A240 Physical Data 155 180 240Trap Condensate Drain III. Field Fabricate DuctworkIV. Make Unit Duct Connections 551A180 and 240 Shown 551A155 ShownUnit Voltage Field Control WiringNEC Electrical Data FLA LRA MCA MOCP†Heater Maximum Minimum Heater Amps Electric Resistance Heater DataUnit PEROptional Convenience Outlet VII. Make OUTDOOR-AIR Inlet AdjustmentsOptional Non-Fused Disconnect Manual Outdoor-Air DamperOutdoor Air Enthalpy Sensor Installation Heat Anticipator SettingsVIII. Install OUTDOOR-AIR Hood Unit StageCO2 Control Setup Discharge Air Thermistor DATDefault Potentiometer Settings Dry Bulb Changeover Set UpEconoMi$er Switchover Control Strategy Mechanical Cooling LockoutIX. Install ALL Accessories Ventilation Air Minimum Position Set UpMotormaster I Control Installation 551A155 and 180 Only Motormaster III Control Installation 551A240 Only Wind Baffle DetailsLlsv LPSXI. Accessory ECONOMI$ER Adjustment III. Refrigerant Service PortsInternal Wiring START-UPFreeze Protection Thermostats Units With Perfect Humidity Dehumidification PackageFan Performance 551A155 With Standard Indoor Fan Motor Watts Bhp Cfm Rpm Watts BhpWatts Bhp Rpm 3750 5100 551A180 15 Tons4800 5700Bhp Rpm Watts 000 551A240 20 TonsWatts Bhp Rpm 500Accessory/FIOP Static Pressure in. wg DropFan RPM at Motor Pulley Settings Evaporator Fan Motor SpecificationsIV. Evaporator FAN Service and Replacement Service CleaningII. Lubrication Evaporator-Fan Pulley Alignment Adjustment Belt Tension AdjustmentVI. CONDENSER-FAN Adjustment VII. ECONOMI$ER AdjustmentFilter Drier VIII. Power FailureIX. Refrigerant Charge XI. Protective DevicesXII. Relief Devices XIV. Replacement PartsXVI. Optional Hinged Access Doors XIII. Control CircuitTypical Wiring Schematic 551A180, 460v Shown Typical Component Arrangement 551A180 Shown Cooling Service Analysis TroubleshootingProblem Cause Remedy EconoMi$er Troubleshooting Problem Potential Cause RemedyPage Electrical TemperaturesGeneral
Related manuals
Manual 170 pages 34.1 Kb