Installation guide

CHECK OPERATION

Before starting the system to check operation of low ambient

temperature controller, ensure that the power wiring and location

of controller assembly are correct. To check operation of low

ambient temperature controller:

1. Turn power on to system.

2. Set thermostat below room temperature.

3. Ensure that there is the standard 3-minute time delay for

the microprocessor controlled high wall fan coil systems.

4. Check time delay of installed accessories:

Under-ceiling (40QAC/QAQ) fan coils using the

duct-free 24-v thermostat delay settings: 2 or 4 minute

delay.

The outdoor-fan motor will not operate until the condensing

pressure reaches the control set point of 225 psig for

38BNC/BNQ models or 362 psig for 38QRF-018-036 and

38QRR-018-060 models (-+ 10 psig). When the set point is

reached, the outdoor fan will cycle to maintain the set point

condensing pressure.

If the low ambient temperature controller does not operate

correctly:

• Ensure that power is being supplied to the system.

• Check condensing pressure: if condensing pressure is

below 200 psig for 38BNC/BNQ models or 321 psig for

38QRF-018-036 and 38QRR-018-060 models, the

outdoor-fan motor should be off and there should be no

voltage across the 2 blue fan power leads coming out of

the controller. If condensing pressure is about 225 psig or

greater for 38BNC/BNQ models or 362 psig for

38QRF-018-036 and 38QRR-018-060 models, the

outdoor-fan motor should be on and will cycle off at

around 200 psig for 38BNC/BNQ or 321 psig for

38QRF-018-036 and 38QRR-018-060 models.

Manufactllrer reserves the right to change, at any time. specifieations and designs without notice and wit hou_ obligations.

Catalo_ No:AG-53DS900-01

Replaces:38 57SI IIK538 09 8