Liebert Comprehensive Troubleshooting for the XDP and Thermostat Password Help

Troubleshooting

6.0TROUBLESHOOTING

Table 16 Troubleshooting the XDP

Symptom	Possible Cause	Check or Remedy
	No main power	Check L1, L2 and L3 for rated voltage.
	Loose electrical connections	Tighten connections.
Pump will not energize	Overloads tripped	Allow pump to cool. Check amp draw.
	Tripped circuit breaker	Check circuit breaker to pump(s).
	Incorrect phase wiring	See Table 5.
	No chilled water	Check and verify that there is supply chilled water to the
		Liebert XDP.
	Isolation valve(s) on pump suction	Open all isolation valves completely during normal
	and/or discharge is closed.	operation.
Pump will not run	Supply chilled water is too high	Check and verify that the chilled water temperature
		setpoint is at 50°F (10°C) or lower and that there is flow
		on the chilled water side.
	Liebert XD cooling modules are Off	Check Liebert XD cooling module to make sure that they
		are On prior to starting the Liebert XDP.
		Check alarm(s) history on Liebert XDP. The Liebert XDP
		was operating below the dew point for a significant
	Low Refrigerant Temperature (high	amount of time. Check humidity in conditioned space,
		lower humidity if necessary to allow Liebert XDP to
	dew point)
		operate at a lower temperature. (Disconnect must be
		switched to Off then back On to allow Liebert XDP to
		reset itself).
		Place the sensor on the RETURN AIR side of the primary
	Incorrect location of	air mover (e.g., Liebert Deluxe System 3). Do not install
	temperature-humidity sensors	the sensor near unsealed doors, windows and similar
		areas.
		Check both differential pressure settings. If not within
	Pressure switch not making contact	6 psi, ±1 psi (41kPa, ±7kPa; 0.41 bars, ±0.07bars) then
		manually change accordingly.
	Not enough charge	See 3.0 - Checklist for Liebert XDP Startup.
	Cavitation due to vapor in pump	Check for adequate charge in system, refer to the User's
Pump noisy		Manual. 3.0 - Checklist for Liebert XDP Startup
	Worn motor bearings	Replace pump
	Low Refrigerant Temperature (High	Check humidity of room along with location of remote
Liebert XDP (Pump)		sensors. Make sure that the sensors are not located in a
	dew point)
suddenly stops		cold area where there is a lack of sufficient air flow.
	Clogged filter/dryer and/or impeller	Clean out debris.
Pipe rattle	Loose pipe connections	Check pipe connections
Chilled water valve not	Motor operates but valve won't open	Check linkage for adjustment and be sure that it is tight on
working		the valve.
	No 24 VAC power to motor	Check for 24 VAC between P2-1 and P2-4.
	No signal from control	Check 24 VAC at P22-1 (close) or P22-3 (open).
Actuator motors		Unplug P22 completely off of the board. Jumper P22-5 to
	Motor not operating	P2-4 for grounding, then jumper P22-1 to P2-1 to drive
		close. Remove jumper to close, and then jumper P22-3 to
		P2-1 to drive open. If motor fails to work, replace it.
	Check control panel for welded
Motor burnout	contactor contacts or welded	Replace defective components.
	overload contacts
Main 24 VAC fuse trips	Shorts or loose connections	Check the wiring connections of the 24 VAC circuit.
	Faulty circuit board	Replace the circuit board.
Unstable pump	R-134a pump loop is overcharged	While pump is running R-134a receiver level must be
operation		within recommended levels (see Figure 21).

31