Liebert user manual Troubleshooting, Liebert XDC troubleshooting

Troubleshooting

7.0TROUBLESHOOTING

Table 24 Liebert XDC troubleshooting

Symptom	Possible Cause	Check or Remedy
	No main power	Check L1, L2, and L3 for rated voltage.
Pump/compressor	Loose electrical connections	Tighten connections.
	Overloads tripped	Allow pump to cool. Check amp draw.
will not energize
	Tripped circuit breaker	Check circuit breaker to pump(s).
	Incorrect phase wiring	See Table 18.
	Isolation valve(s) on pump suction	Open all isolation valves completely during normal operation.
	and/or discharge is closed.
	Liebert XD cooling modules are Off.	Check Liebert XD cooling modules to make sure that they are
		ON prior to starting the Liebert XDC
		Check alarm(s) history on Liebert XDC. The Liebert XDC was
		operating below the dew point for a significant amount of
	Low Refrigerant Temperature	time. Check humidity in conditioned space; lower humidity if
	(high dew point)	necessary to allow Liebert XDC to operate at a lower
Pump will not run		temperature. (Disconnect must be switched to Off then back
		to On to allow Liebert XDC to reset.)
	Incorrect location of	Place the sensor on the return air side of the primary air
		mover (I.e., Liebert Deluxe System 3). Do not install the
	temperature-humidity senors
		sensor near unsealed doors, windows and similar areas.
		Check both differential pressure settings. If not within 6 psi,
	Pressure switch not making contact	±1 psi (41 kPa, ±7kPa; 0.41 bars, ±0.07 bars) then manually
		change accordingly.
	Not enough charge	See 2.7 - Filling the Direct Expansion (DX) Circuit—R-
		407c.
		Check for adequate charge in system, refer to the user
	Cavitation due to vapor in pump	manual. 2.7 - Filling the Direct Expansion (DX) Circuit—R-
Pump noisy		407c
	Pump is rotating in reverse	See Table 18
	Worn motor bearings	Replace pump
	Low Refrigerant Temperature	Check humidity of room along with location of remote
		sensors. Make sure that the sensors are not located in a cold
	(high dew point)
		area where there is a lack of sufficient air flow.
Liebert XDC (Pump)	Loss of power	When power is restored, the Liebert XDC will automatically
suddenly stops		restart.
	Clogged filter/dryer and/or impeller	Clean out debris.
	Leak in system - loss of charge	Check the entire system for leaks with a refrigerant sniffer.
		Repair as necessary.
	Lack of load in the room	If there is no cooling required, turn the Liebert XDC off at the
		I/O button.
Room becomes	Minimum room temperature setpoint	Check the setpoint by following instructions in 5.3.2 -
	is too low.	SETPOINTS.
too cold
	Incorrect location of temperature-	Place the sensor on the return air side of the primary air
		mover (i.e., Liebert Deluxe System 3). Do not install the
	humidity senors.
		sensor near unsealed doors, windows, and similar areas.
Table continued on following page

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