WhisperKool 4000 - System Operation

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Ceiling Mount
Initial Start-Up
Set the thermostat to COOL and fan switch to AUTO. Lower
the setpoint to the desired cellar temperature. (A temperature
of 55°F is the recommended setpoint.) See thermostat
instructions for details.
Normal System Cycle
The thermostat should turn the cooling system on when it
senses a temperature one (1) degree higher than the setpoint.
See thermostat instructions for details.
Anti-Short Cycle
Most thermostats have a safety feature that will prevent
the condensing unit from cycling on and o within a short
period of time. During the anti-short cycle, the condensing
unit will typically remain o for 5-7 minutes. See thermostat
instructions for details.
Fan Operation
If the fan switch on the thermostat is in the AUTO position, it
will run only during the cooling cycle. If the fan switch on the
thermostat is in the ON position, the fan will continuously run
until the switch is set back to the AUTO position.
Anti-Frost
Systems equipped with a 24V thermostat conversion kit do
NOT have an anti-frost feature. To reduce the possibility of the
evaporator coil icing up, avoid setting the thermostat lower
than 55°F.
Operation in Low Ambient Temperatures
The condensing unit comes equipped with a LAC (Low
Ambient Control). The LAC is a three-way modulating valve that
responds to discharge pressure. When the discharge pressure
falls below the valve’s dome pressure, the valve modulates
open to the discharge port which allows discharge gas to
bypass the condenser. Mixing the discharge gas with the liquid
creates high pressure at the condenser outlet, reducing the
ow and causing liquid to backup in the condenser. Flooding
the condenser reduces the area available for condensing.
This reduction in condenser surface area results in a rise in
condensing pressure during cold ambient conditions.
The condensing unit controller comes preset from the factory
with the cut-in pressure at 25psi and the cut-out pressure
at 15psi. During low ambient temperatures (40°F or below),
it will be necessary to adjust the cut-in pressure to 10-15psi
(15psi preferred) and the cut-out to 5psi to ensure compressor
startup. See page 33 of the technician's manual for instructions
on adjusting the cut-in and cut-out pressures of the condensing
unit.
NOTE: To ensure correct system operation, the 24V thermostat
must be placed inside the wine cellar, preferably in a central
location away from any airow.
SYSTEM OPERATION
The cooling system is equipped with the hardware needed to support a 24-volt air conditioning thermostat (not included).