1
5
On a Call for Heat:
1.
The thermostat will send the appropriate signal to the circuit board.
Zone 1= Y1, G or W
Zone 2,3,4=W
2.
The control panel pump will start and de-energize the solenoid for the zone that is calling.
3.
The H
eatPum
Pro will consider the Balance Point (BP) setting if auxiliary heat is fossil fuel or Aux
Balance Point
is set to True:
a.
If the OAT is above the BP setting the Y1 and G signal will be sent to the air handler and a Y1
signal
will be sent to the condenser (O
/B
will also be energized if set for Rev Valve Energized
in Htg
mode).
b.
If the OAT is below the BP setting then W1 will be energized to initiate back-up fuel operation,
W2 will be controlled by the zone weight logic.
c.
If the BP setting is set for “Lock
in Backup Heat
” then all heat calls will be served with a W1
output (fossil fuel)
regardless of the OAT. W2 will be controlled by the zone weight logic.
4.
The LAT sensor will start to monitor the air in the supply plenum.
The sensor will be looking for the
temperature set for the "Heat Stage Threshold" in the Set-Up Wizard plus an OAT adjustment. The
threshold temperature will raise 1˚ for every 2˚ drop in OAT below 30˚F.
Ex. HST = 100˚F in Set-up Wizard:
30˚F OAT
100˚F LAT threshold
20˚F OAT
105˚F LAT threshold
5.
The LAT sensor will continue to monitor the supply air temperature. If the temperature levels off below the
heat stage threshold setting for more than three minutes, the HeatPumPro will send a signal to Y2 on the
condenser.
6.
The LAT sensor will continue to monitor the supply air temperature and continue to stage up until all stages
of heat are on or the heat stage threshold temperature is met. With an all electric system the HeatPumPro
will
stage the electric heat on with the heat pump running, with a fossil fuel backup it will turn off the heat
pump
and run the back-up heat only when a W1 or W2 signal is sent.
7.
If the temperature in the supply plenum reaches the auxiliary high limit it will begin to stage down the
equipment while still maintaining a temperature above the Heat Stage Threshold.
8.
When the zone is satisfied the equipment will turn off, the zone will stay open for two minutes and then run
the pump for the time set in the secondary purge time in the Set-Up Wizard to open the rest of the dampers
and
allow for a “soft-start” on the next cycle.
On a Call for Cooling:
1.
The thermostat will send the appropriate signal to the circuit board
: Y1, G, O or Y1, G for zone 1
depending on the thermostat type; Y, G for zones 2, 3, or 4.
2.
The pump will start and de-energize the solenoid for the zone that is calling.
3. The Y1, Y2, G signal will be sent to the air handler if the "Air Handler Stage Threshold%" (AHST) is met.
Otherwise, only Y1, G will be sent to the air handler. A Y1 signal will be sent to the condenser, and an O/B
will be sent if set for Rev Valve Energized in Cooling.
4.
The LAT sensor will monitor the supply air temperature in the plenum and look for the temperature set in the
cool stage threshold in the Set-Up Wizard. If the LAT sensor senses a continuous decrease in temperature
it will leave the system in first stage cooling.
5.
If the LAT sensor senses the supply air temperature leveling off below the setting it will start a three minute
timer. If the supply temperature does not reach the setting in three minutes it will send a Y2 signal to the
condenser.
6.
If the supply air temperature reaches the cooling low limit setting the signal to Y2 will be removed.
7.
When the zone is satisfied the equipment will turn off, the zone will stay open for 30 seconds and run the
pump for the time set in the secondary purge time in the Set-Up Wizard to open the rest of the dampers
and allow for a “soft-start” on the next cycle.
Sequence of Operation
