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ARTC-SVX001B-EN
13. Symptom: Compressor thermal protector switch open
Possible Causes
Potential Solutions
Operating beyond design conditions
Check fan switch or fan pressure settings as appropriate
Discharge valve partially shut
Open valve
Faulty compressor overload
Replace overload if external type provided
14. Symptom: No low voltage (24 Vac)
Possible Causes
Potential Solutions
Control circuit fuse open
Check fuse prong contact points; replace fuse
Phase monitor opened or tripped
Check for correct voltages
Transformer
T1
defective
Replace transformer
T1, T2, T3
No primary voltage on
T1
Check breakers, fuses; check power supply specifications
15. Symptom: Thermal Expansion valve superheat too high
Possible Causes
Potential Solutions
Water/glycol temperature too warm
Low refrigerant level; recharge chiller
Obstructed filter dryer
Replace dryer core
Low refrigerant charge
Recharge refrigerant as per data plate
Improperly adjusted superheat valve setting
Reset valve settings to factory specifications
16. Symptom: Thermal expansion valve superheat too low
Possible Causes
Potential Solutions
Sensing bulb not properly located
Check if secured to pipe or insulated; check sensor position on pipe at
4-8-10-2 clock positions
Defective thermostatic element
Replace power head
Valve adjusted too far open
Re-adjust to 10° to 12°(scroll) or 13° to 16°(digital scroll)
17. Symptom: Contactor/relay inoperative
Possible Causes
Potential Solutions
Coil shorted or open
Replace coil
Mechanical parts broken or jammed
Replace assembly
Contacts pitted or burned
Replace contactors
No 24 Vac to coil
Replace secondary fuse to
T2
transformer
18. Symptom: Freeze protection safety activated
Possible Causes
Potential Solutions
Thermostat set too low
Reset above freezing temperature at evaporate or discharge
Low water flow
Remove restrictions. Increase HP
Low suction pressure
See “low suction pressure”