Seabreeze PTAC09CH3ZX, Service Manual

Page: 4 / 15

953-0002-revC 07/06/09
PAGE 4
When Heat Pump and electric heat is working the system will operate as follows:
(Tp= Indoor coil temperature, Tr=Room temperature, Ts=Temperature setpoint)
1. If Tp≥78
℉
and Tp≥Tr+9ºF, Blower fan will start and run.
2. Tp≤64
℉
or Tp
＜
Tr+9ºF Blower fan will stop (to eliminate cold air draft)
3. Tp≥78
℉
and Tr+9f ≤Tp
＜
Tr+18 ºF Blower fan will run at set speed after running for 5 minutes at
low speed.
4.Tp≥78
℉
and Tp≥Tr+18 ºF Blower fan will run at set speed after running for 2 minutes at low speed.
5. When the compressor starts, Blower fan will run at set speed. If Outside temperature is below
47 º F, the heat pump portion if the unit will not work. All heat will be obtained by the operation of
the Electric heaters.
●
When the room temperature is less than Ts-3.6ºF (Ts is the setpoint temperature), the
compressor and outdoor fan will run.
●
When the room temperature is more than or equal to the set temperature (Ts), the
compressor and outdoor fan will shut down.
●
In order for the electric heat to operate, the following conditions must be met:
①
The compressor, outdoor fan, and the indoor blower fan must be operating
②
The room temperature
≤
the set temperature (Ts)
－
5.4ºF and the room temperature
≤
73.4ºF
③
the temperature of indoor coil (Tp) < 122ºF
●
The electric heat will shut-down in the heating mode on any of the following conditions:
①
The compressor or indoor blower fan stops
②
The room temperature ≥ the set temperature
－
5.4ºF and room temperature ≥73.4ºF
③
the temperature of inside coil pipe > 122ºF
●
To purge latent heat from the unit, the indoor fan will operate for 50 seconds after the
electric heat (or heat pump function) stops.
Electric
heating
O
n