Omega VSHPe Series - Troubleshooting Guide; Unit Problem Diagnosis

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