Friedrich SH20L50-A, SH20L30-A, SH15L30-A manual Troubleshooting, Problem Possible Cause To Correct

Page 12

TROUBLESHOOTING (Continued)

PROBLEM

POSSIBLE CAUSE

TO CORRECT

 

Compressor attempts to start

Allow a minimum of two (2) minutes to allow pressures to

 

before system pressures are

 

equalize before attempting to start.

 

equalized.

 

 

 

 

Check voltage with unit operating. Check for other

COMPRESSOR

Low or fluctuating voltage.

appliances on the circuit. Unit should be on separate

 

circuit for proper voltage, and be fused separately.

ATTEMPTS TO

 

START, OR RUNS

Incorrect wiring.

Connect per wiring diagram.

FOR SHORT

Shorted or incorrect capacitor.

Check by substituting a known good capacitor of correct

PERIODS ONLY.

rating.

 

CYCLES ON

Restricted or low air flow through

Check for proper fan speed or blocked condenser.

OVERLOAD.

condenser coil.

 

 

Compressor running abnormally

Check for kinked discharge line or restricted condenser.

 

hot.

Check amperage.

 

Overload opens too soon.

Change compressor if all other corrections above are

 

normal.

 

 

 

 

 

 

Thermostat contacts not closing.

Check continuity of thermostat at coldest setting. Jump

 

contacts, if compressor runs, replace thermostat.

 

Low voltage supply.

Check for nameplate voltage.

 

Switch (On-Off) inoperative.

Test for continuity.

COMPRESSOR

Open capacitor.

Check by substituting a known good capacitor of correct

DOES NOT START -

rating.

 

FAN MOTOR RUNS.

Internal overload open.

Check voltage at compressor terminals. If voltage is

 

satisfactory, replace compressor.

 

 

 

Relay open

Replace relay

 

Open or shorted compressor

Check windings for continuity and resistance. Direct test

 

windings

compressor. If direct test fails, replace compressor.

 

 

 

 

Thermostat open or inoperative.

Set to coldest position. Test thermostat and replace if

 

necessary.

 

 

 

Dirty air filter.

Clean as recommended in Owner’s Manual.

DOES NOT COOL,

Dirty or plugged condenser or

Use steam or detergents to clean.

evaporator coil.

OR COOLS ONLY

 

Poor air circulation in area being

 

SLIGHTLY.

Adjust air louvers.

cooled.

 

 

 

Low capacity - undercharge.

Clean, check for leak and make repair.

 

Compressor not pumping

Check amperage draw against nameplate. If not

 

properly.

conclusive, make pressure test.

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Contents Service & Parts Manual Table of Contents Performance Data Cooling Component Operation and Testing Testing ProceduresCompressors Line Voltage OverloadGround Test Checking Compressor EfficiencyFAN Motor Test CAPACITOR, RUN Capacitor TestThermostat RangeTest LOW Ambient Bypass Valve Figure Sealed Refrigeration System Repairs Equipment RequiredEquipment Must be Capable Hermetic Component Replacement Special Procedures in the Case of Compressor Motor BurnoutRotary Compressor Special Troubleshooting and Service Refrigerant ChargeTroubleshooting Problem Possible Cause To Correct Unit does not RUNTroubleshooting Problem Possible Cause To CorrectFAN Motor does Wiring Diagram Models SH15L30-A, SH20L30-A, SH20L50-AHazardgard Cabinet Parts Hazardgard Chassis Parts Hazardgard Parts List Description Part NO# Models Code Electrical PartsOptional Accessory Items Page Use Factory Certified Parts