Troubleshooting Checklist - Trane EXWA Installation Manual

Problem
No response to any
thermostat setting
Unit short cycles
Insufficient capacity
High pressure switch open
High head pressure
Low suction pressure
Low Pressure switch open
Freezestat open
28
Troubleshooting
Checklist
Heating Cooling Cause
X X Main power off
X X Defective control transformer
X X Broken or loose connection
X X Defective thermostat
X X Transformer
X X Thermostat or sensor improperly located
X X Low on refrigerant charge
X X Restricted thermal expansion valve
X X Defective reversing valve
X X Thermostat improperly located
X X Unit undersized
X X Inadequate water flow
X X Scaling in heat exchanger
X Water too hot
X Water too cold
X Inadequate GPM
X Water too hot
X X Overcharged with refrigerant
X X Defective pressure switch
X Trash in heat exchanger
X Low water flow
X X Overcharge of refrigerant
X X Non-condensable in system
X X Water too hot
X X Undercharged
X X Restricted thermal expansion valve
X Inadequate GPM
X Inadequate GPM
X Water too cold
X X Undercharged with refrigerant
X X Defective pressure switch
X X Heat transfer fluid too cold
X Inadequate GPM
X Water too cold
X X Defective freezestat
X Heat transfer fluid too cold
Correction
Check fuses
Replace
Repair
Replace
Reset Transformer
Relocate
Locate leak, repair and recharge by
weight (not by superheat)
Replace
See WSHP-IOM-# for touch test chart
Relocate
Recalculate heat gains/losses
Increase GPM
Clean or replace
Decrease temperature
Increase temperature
Increase water flow to unit
Decrease temperature
Decrease charge
Check or replace
Backflush
Increase GPM
Decrease charge
Evacuate and recharge by weight
Decrease temperature
Locate leak, repair and recharge
Repair / replace
Increase GPM
Increase GPM
Increase temperature
Increase charge
Replace
Raise water temperature. For smaller
tonnage units, switch pressure switch
wires from 35 psig to 7 psig
Increase GPM
Increase GPM
Replace freezestat
Replace freezestat. For smaller tonnage
units, switch pressure wires from 35 psig
to 7 psig.
WSHP-SVX02A-EN