Trane WPWD Troubleshooting Checklist, Problem No response to any thermostat setting, Heating

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

Troubleshooting

Checklist

Heating	Cooling	Cause	Correction
X	X	Main power off	Check fuses
X	X	Defective control transformer	Replace
X	X	Broken or loose connection	Repair
X	X	Defective thermostat	Replace
X	X	Transformer	Reset Transformer
X	X	Thermostat or sensor improperly located	Relocate
X	X	Low on refrigerant charge	Locate leak, repair and recharge by
			weight (not by superheat)
X	X	Restricted thermal expansion valve	Replace
X	X	Defective reversing valve	See WSHP-IOM-# for touch test chart
X	X	Thermostat improperly located	Relocate
X	X	Unit undersized	Recalculate heat gains/losses
X	X	Inadequate water flow	Increase GPM
X	X	Scaling in heat exchanger	Clean or replace
	X	Water too hot	Decrease temperature
X		Water too cold	Increase temperature
	X	Inadequate GPM	Increase water flow to unit
	X	Water too hot	Decrease temperature
X	X	Overcharged with refrigerant	Decrease charge
X	X	Defective pressure switch	Check or replace
	X	Trash in heat exchanger	Backflush
	X	Low water flow	Increase GPM
X	X	Overcharge of refrigerant	Decrease charge
X	X	Non-condensable in system	Evacuate and recharge by weight
X	X	Water too hot	Decrease temperature
X	X	Undercharged	Locate leak, repair and recharge
X	X	Restricted thermal expansion valve	Repair / replace
X		Inadequate GPM	Increase GPM
X		Inadequate GPM	Increase GPM
X		Water too cold	Increase temperature
X	X	Undercharged with refrigerant	Increase charge
X	X	Defective pressure switch	Replace
			Raise water temperature. For smaller
X	X	Heat transfer fluid too cold	tonnage units, switch pressure switch
			wires from 35 psig to 7 psig
X		Inadequate GPM	Increase GPM
X		Water too cold	Increase GPM
X	X	Defective freezestat	Replace freezestat
			Replace freezestat. For smaller tonnage
X		Heat transfer fluid too cold	units, switch pressure wires from 35 psig
			to 7 psig.

28 WSHP-SVX02A-EN