Humidifying; Dehumidifying; Checking Refrigerant Charge Capacity Of Lee-Temp Outdoor Unit - Liebert DM Series User Manual

setpoint to 5°C (10°F) lower than the indoor temperature. If the heater stops working, it means that the heating
function is normal.

Note
Restore the temperature setpoint to the default or the original value after the test.

4.2.3 Humidifying

Adjust the humidity setpoint according to 5.6.3 Set Points to 10% higher than the indoor relative humidity. Then the
control system should trigger the humidifying demand and the humidifier starts to work. Adjust the humidity setpoint to
10% lower than the indoor relative humidity. If the humidifier stops working, it means that the humidifying function is
normal.

Note
Restore the humidity setpoint to the default or the original value after the test.

4.2.4 Dehumidifying

Adjust the humidity setpoint according to 5.6.3 Set Points to 10% lower than the indoor relative humidity. Then the
control system should trigger the dehumidification demand and the fan runs at low speed. Adjust the humidity setpoint
to 10% higher than the indoor relative humidity. If the fan automatically runs at high speed, it means that the
dehumidification function is normal. Note that during the testing process, if the indoor temperature is 3°C higher than
the temperature setpoint, the system may enter a forced cooling mode and the dehumidification demand will not be
responded.

Note
Restore the humidity setpoint to the default or the original value after the test.

4.2.5 Checking Refrigerant Charge Capacity Of Lee-Temp Outdoor Unit

The Lee-Temp outdoor unit has been charged with refrigerant before delivery. Check whether the refrigerant charge
capacity is proper after powering on by using the following method.
When the high pressure is not lower than 240psig (16.5bar), the liquid level of the refrigerant will reach the 1/2 point
of the tank sight glass. When the ambient temperature is low and the high pressure cannot meet the requirement, you
can block part of the upside and downside of the air intake uniformly to obtain required pressure.
If the liquid level cannot meet the requirement, you should discharge or refill the refrigerant for a proper liquid level
length. Reclaim the discharged refrigerant according to correlative requirement.
New Liebert_DM Series Air Conditioner User Manual
Chapter 4 System Testing 25