OMEGA-VSHPe.F-IOM-2205
19
Troubleshooting Guide
Problem
Mode
Time To
Trip
Possible Cause(s)
Likelyhood to
occur
Correction Method
Heating/Cooling
Main power off
Med
Check unit circuit breaker.
Heating/Cooling
Blown transformer / Blown
Low Voltage Fuse
High
3 Amp fuse pops usually when there is a short to ground. Check thermostat wiring, control wiring,
and verfiy wiring in chassis has no short to ground.
Heating/Cooling
Blown transformer / Blown
Low Voltage Fuse
High
Short to ground inside chassis. Open top cover of chassis cover, check for shorts, signs of arcing,
loose connectors and worn shielding especially near refrigerant piping.
Heating/Cooling
Blown transformer / Blown
Low Voltage Fuse
High
Confirm there is no short to ground before replacing transformer. Built in 3A fuse is designed to
protect transformer. If no short to ground found, replace transformer.
Heating/Cooling
Broken or loose connection
High
Check for loose thermostat connections at the control board and at thermostat base. Repair and/or
tighten as required.
Heating/Cooling
Damaged thermostat cable
Low
Check for damaged wires on the thermostat cable
Heating/Cooling
Defective thermostat
Med
Check and replace
Unit short cycles
Heating/Cooling
Thermostat improperly located
Low
Relocate thermostat away from supply registers.
Breaker Trip
Heating/Cooling
0min
Short to ground on high
voltage side
Low
Isolate main components: disconnect chassis harnesses and fan harness from electrical box. Check
by turning on breaker and then disconnect. If Breaker trips again, the short to ground inside the
electrical box. Using ohm meter check for short to ground inside electrical (check for loose wires, or
damaged wire shielding). Otherwise short to ground is located inside the chassis or at the fan motor.
Heating/Cooling
0min
Tripped Circuit Breaker
Low
Disconnect chassis power harness only. Power up unit. If breaker trips only when chassis is
connected, check chassis power wiring for a potnential locked rotor. Compare current reading
(Amps) to nameplate.
Heating/Cooling
Burnt out compressor
overload
High
Check and replace if required. Located on top of Rotary compressor. Remove plastic cap, check
resistance (size 020-060 units only).
Heating/Cooling
Defective compressor
contactor
Low
Check 24VAC coil on contactor is getting power. If powered but coil does not close line voltage
contacts or stays open/close replace contractor. Replace every 5-7 years.
Heating/Cooling
Supply voltage too low
Low
Correct incoming supply voltage setting at Transformer. Check that the line voltage is matched to
208V or 240V transformer taps
Heating/Cooling
Defective compressor
capacitor
Med
Check capacitor and replace if required. Should be replaced every 4-5 years.
Heating/Cooling
Defective compressor
windings
Low
Check compressor windings for damage. Replace if required
Heating/Cooling
0 - 3min
Limit switches open
Check for faulty pressure switches. Switches are normally closed. Check for bad connections at wire
terminals. Replace if switches are open when unit is shutdown and there are no wire connections
issues.
Heating/Cooling
0min
Clogged Drain Pan /
Condensate hose / Faulty
Sensor
Condensate switch detects overflow condition in drain pan, check for obstruction. If no water is
present and condensate switch is circuit is open, check switch, and replace if required.
Heating/Cooling
Dirty filter
High
Check and replace
Heating/Cooling
Blower RPM too low
Low
Set to blower to higher fan speed using unit mounted 3-speed fan switch.
Heating/Cooling
Loss of conditioned air due to
ductwork leaks
Low
Check for duct leaks and repair
Heating/Cooling
Low on refrigerant charge
Med
Possible leak in system or low charge. Check for low suction pressure (<110PSI); coil freeze up. If
confirmed check for leaks at piping joints and coil. Repair if possible, and recharge to unit nameplate
charge rating.
Heating/Cooling
Defective reversing valve
Low
Check and replace
Heating/Cooling
Thermostat improperly located
Med
Relocate thermostat
Heating/Cooling
Inadequate water flow
Low
Increase GPM
Cooling
Entering Water Temperature
too hot
Med
Adjust EWT Loop temperature lower
Heating/Cooling
Entering Water Temperature
too cold
Low
Adjust EWT Loop temperature higher
Cooling
30sec - 2min
Inadequate GPM
High
If auto shut-off valve is installed, check that control valve actuator opens during call for Heating. Set
valve to manual mode and remove power connections from actuator and re-test. If manual mode re-
test confirms proper water flow, actuator is likely faulty.
Cooling
>2min
Water too hot
Med
Reduce water loop temperature
Heating
>2min
Inadequate air flow
Med
Check for clogged filter, check blower for obstruction and adequate airflow.
Heating
>5min
Dirty filter
Med
Clean/replace
Heating/Cooling
>5min
Overcharged with refrigerant
Low
TXV will hunt, Superheat will oscillate, read close to zero. Decrease charge/Confirm charge matches
nameplate.
Heating/Cooling
0min
Bad pressure switch
Low
Check continuity, should be closed circuit. If open circuit, check wiring inside chassis: tab,
connectors.
No response to any
thermostat setting
Insufficient capacity
High Pressure Fault
Only blower runs,
but not compressor
