Seresco CLASSIC NE-002, Operation And Maintenance Manual

Page: 29 / 37

K – R3 Module
K ‐
4
Compressor Circuit Operation – Dehumidifier with “Full AC with No Outdoor Condenser”:
Piping schematic for compressor circuit is shown on Pic. K.3 below.
When a demand requires the compressor to operate, the following sequence occurs:

Once blower operation, related safeties and timers are confirmed by the control system, the pump down
solenoid valve opens and once pressure stabilizes, the compressor starts.

Reheat valve diverts portion of hot gas into the reheat coil. Remainder of the hot gas goes through pool valve
into AC heat exchanger (evaporative cooling coil) and/or full flow pool water heat exchanger.

Pool valve diverts portion of hot gas into full flow pool water heat exchanger or evaporative cooling coil. If any
amount of heat is diverted into the evaporative cooling coil:
o
R3 module exhaust fan is controlled as outdoor condenser fan: its speed is based on compressor head
pressure level (see Outdoor Condenser and Fluid Cooler Operation ).
o
once compressor head pressure exceeds the pre ‐ set level, condensate pump is engaged – air moisture,
condensed in the dehumidifier’s evaporator coil and collected in the R3 module drain pan, is pumped
through the nozzle manifold and sprayed onto the evaporative condenser coil to increase heat
rejection, thus maintaining compressor head pressure.

Once demand for the compressor’s operation is removed (respective call is satisfied), the pump down solenoid
valve closes; once the compressor suction pressure reaches the pre ‐ set pressure, the compressor stops
Pic. K.3