Manual 2100-583G
Page
29 of 48
PART LOAD COOLING
When the thermostat system switch is placed in “COOL”,
it completes a circuit from “R” to “O”, energizing
the reversing valve solenoid. On a call for cooling,
the thermostat completes a circuit from “R” to “Y1”
sending the signal to the Geothermal Logic Control. The
Geothermal Logic Control verifies that the High Pressure
Switch, the Low Pressure Switch, and the Flow Switch
control are all in the closed position. It then energizes the
“A” terminal output to start the flow center (Ground Loop
Applications) or energizes the water solenoid (Ground
Water/Water Loop Applications). Following 10 seconds of
the “A” terminal energization, the compressor contactor is
energized.
FULL LOAD COOLING
The unit should already be operating in Part Load Cooling
operation prior to Full Load Cooling being energized
(see above). Additionally, what occurs, the thermostat
completes a circuit from “R” to “Y2”. This sends a
signal to the compressor staging solenoid (plug on side of
compressor).
PART LOAD HEATING
When thermostat is placed in “HEAT”, the reversing valve
solenoid is no longer energized. On a call for heating,
the thermostat completes a circuit from “R” to “Y1”
sending the signal to the Geothermal Logic Control. The
Geothermal Logic Control verifies that the High Pressure
Switch, the Low Pressure Switch, and the Flow Switch
control are all in the closed position. It then energizes the
“A” terminal output to start the flow center (Ground Loop
Applications) or energizes the water solenoid (Ground
Water/Water Loop Applications). Following 10 seconds of
the “A” terminal energization, the compressor contactor is
energized.
SEQUENCE OF OPERATION
FULL LOAD HEATING
The unit should already be operating in Part Load Heating
operation prior to Full Load Cooling being energized
(see previous). Additionally, what occurs, the thermostat
completes a circuit from “R” to “Y2”. This sends a
signal to the compressor staging solenoid (plug on side of
compressor).
GEOTHERMAL LOGIC CONTROL –
If the controller
operates in normal mode, the Green Status Light blinks.
This indicates that 24 volt power is applied to the board
and the controller is running in normal operation.
On initial power up and call for compressor operation, a
5-minute delay + a random start delay of 0 to 60 seconds
is applied. After the random delay, the compressor relay
is energized (Terminal “CC”). When the “Y” input opens
the compressor de-energizes.
NOTE:
The time delay + random start can be disabled by
removing the Test jumper on the Geothermal Logic Control
Board. However, this is NOT recommended. This is only
intended to be a function for factory run-in processes.
Water Solenoid –
When “Y” signal is sent to Geothermal
Logic Control, the water solenoid output “A” terminal
will energize 10 seconds prior to “CC” output that starts
compressor.
NOTE:
The 10-second time delay between the energization
of the "A" terminal and the "CC" terminal can be disabled
by removing the WSD jumper on the Geothermal Logic
Control Board.
Anti-Short Cycle Timer –
After compressor shut-down,
or power disruption, a 5-minute timer is applied and
prevents the compressor from operating.
“WSD”
JUMPER
“TEST”
JUMPER
“O/V”
JUMPER
