York YCAL0014SC Service and Troubleshooting, Problem, Cause, “Low Suction Pressure”, Fault Cont’D

Service and Troubleshooting

PROBLEM		CAUSE		SOL
“LOW SUCTION PRESSURE”	4. TXV defective.		4.	Replace TXV.
FAULT (CONT’D)
	5.	Reduced flow of chilled	5. Check GPM (See “Limitations”
		liquid through the cooler.		in Installation section). Check
				operation of pump, clean
				pump strainer, purge chilled
				liquid system of air.
	6.	Defective suction pressure	6.	Replace transducer/low
		transducer/low pressure		pressure switch or faulty
		switch or wiring		wiring. Refer to “Service”
				section for pressure/voltage
				formula.
	7.	LLSV defective	7. Replace LLSV
“HIGH DISCHARGE	1. Condenser fans not operating		1.	Check fan motor, fuses,
PRESSURE” FAULT		or operating backwards.		and contactors. Assure fan
				blows air upward.
	2.	Too much refrigerant.	2.	Remove refrigerant.
	3.	Air in refrigerant system.	3.	Evacuate and recharge
				system.
	4.	Defective discharge	4.	Replace discharge pressure
		pressure transducer.		transducer. Refer to Service
				section for pressure/voltage
				formula.
“LOW LIQUID TEMP”	1. Improperly adjusted leaving		1.	Re-program the leaving
FAULT		chilled liquid temp cut-out		chilled liquid temp. cut-out.
		(glycol only).
	2.	Micropanel setpoint/range	2.	Re-adjust setpoint/range.
		values improperly programmed.
	3.	Chilled liquid flow too low.	3.	Increase chilled liquid flow –
				refer to Limitations in Instal-
				lation section.
	4.	Defective LWT or RWT sensor.	4.	Compare sensor against a
		(assure the sensor is properly		known good temperature
		installed in the bottom of the well		sensing device. Refer to
		with a generous amount of heat		Service section for temp/
		conductive compound)		voltage table.
				CONT’D

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