Troubleshooting Guide

8	Troubleshooting Guide


Problem	Possible cause	Solution
		Check main disconnect
	No power.	fuses, wiring, and power lead
		to the unit.
	Wrong voltage supplied to	Voltage must be within plus
Chiller will not run.	Wrong voltage supplied to	or minus 10% of the
Chiller will not run.	the chiller.	nameplate rating.
	Defective on/off switch.	Replace.
	Control circuit fuse blown.	Replace, check the
	Control circuit fuse blown.	transformer.
		transformer.
	Defective control transformer.	Replace.
Pump runs, compressor	No process load on the	Increase the process load.
Pump runs, compressor	chiller.	Increase the process load.
cycles at short intervals.	chiller.
cycles at short intervals.	Refrigerant is low.	Check the refrigerant charge.
	Refrigerant is low.	Check the refrigerant charge.
	Refrigerant is low.	Check the refrigerant charge.
		Make sure that the coolant
The leaving water		solution is right for the
The leaving water	Improper water/glycol	process — must be 75%
temperature is too high.	Improper water/glycol	process — must be 75%
temperature is too high.	solution.	water and 25% glycol.
	solution.	water and 25% glycol.
		See Figure 5 on Page 17 for
		more information.
Pump pressure is low (see	Check for foreign matter.	Clean the system.
pump curves).	Check for foreign matter.	Clean the system.
pump curves).
Pump pressure is too high.	Restricted water flow.	Check for partially closed
Pump pressure is too high.	Restricted water flow.	valves, etc. Be sure all lines
		are properly sized.

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Sterling A0544325 installation manual Troubleshooting Guide, Problem Possible cause Solution