Orion System Water Source Heat Pump Module - Manual (Page 12)

Water Source Heat Pump Module
Technical Guide 12
Sequence of Operation
Stand-Alone Input Commands
Compressor On/Off
A 24 volt signal to Binary Inputs #1-4 initiates each Compressor’s On
function. The source for this signal would typically come from Y1 to
Y4 calls from the thermostat.
Cool Enable On/Off
A 24 volt signal on this input indicates the unit is in the Cooling Mode.
Typically, the source for this signal is the “O” call from the thermo-
stat.
Water Proof of Flow Circuit On/Off
A 24 volt signal to Binary Input #6 indicates Water Proof of Flow for
each circuit.
Suction Pressure Analog Inputs
Sensors from Analog Inputs #1 & #3 correlate with the Suction Pres-
sure of each Circuit (250 PSI). Pres 1 input correlates with Circuit A’s
1
st and 2 nd compressor. Pres 3 input correlates with Circuit B’s 1 st and
2 nd compressor. Suction Pressure Transducer is 0-250 psi.
Leaving Water Temperature Thermistor Inputs
T1 for Heating Mode measures the temperature of the leaving water to
prevent freezing of the coil.
Input Commands (VCM-X WSHP )
NOTE: When the term “ON” is used, it means there is either 24
VAC on the appropriate Binary Input or a call-to-run
signal is being received from the VCM-X WSHP. When
the term “OFF” is used, it means there is either 0 VAC
on the appropriate Binary Input or the call-to-run signal
from the VCM-X WSHP has been removed.
Compressor On/Off
Instead of a physical input signaling the Compressor On/Off function,
the VCM-X WSHP Controller communications drives the Compressor
On/Off function.
Cool Enable On/Off
As with the Compressor On/Off function, the VCM-X Controller
communicates to the Module that it is in Heat Mode. On = Cool. Off
= Heat.