Function And Control - Sea Breeze PTAC49CH3ZX Service Manual

1. Temperature Parameter
• Indoor setting temperature (Tpeset)
• Room temperature (Tamb)
2. System Basic Function
In any circumstances, the compressor will delay 3 minutes for protection once it's stated up. Once the
compressor is started up, the compressor won't stop with the change of the indoor temperature. While once
the compressor is stopped, it can be started up only after 3 minutes delayed. (The compressor can be
stopped immediat4ely at the time of mode switchover, turning off the unit, adjusting setting temperature and
turning to protection functions.)
1) Cooling Mode
Working conditions and process for cooling:
When Tamb ≥ Tpreset +2 ℉(1 ° C), the unit is running in cooling mode. Meanwhile, the compressor is
running and the fan is running at the setting fan speed.
When Tamb ≤ Tpreset -2 ℉(1 ° C) , the unit turns off. Meanwhile, the compressor will stop, and the fan will
run at the setting fan speed.
When Tpreset -2 ℉(1 ° C) < Tamb < Tpreset +2 ℉(1 ° C), the unit keeps previous running status.
* In this mode, the unit displays the setting temperature and the cooling LED is illuminated. The setting
temperature range is 60 ~ 90 ℉ (16 ~ 32 ° C)
2) Fan Mode
In this mode, the compressor won't run and the temperature can't be adjusted (UP and DOWN are invalid).
The fan can be selected at high, medium and low fan speed. The unit displays ambient temperature (32 ~
99 ℉, when ambient temperature is higher than 99 ℉, it will display H1. When ambient temperature is
lower than 32 ℉, it will display L0), and the fan LED is illuminated.
3) Heating Mode
For cooling only with electric heater units, working conditions and process for heating:
When Tamb ≤ Tpreset -2 ℉(1 ° C), the unit is running in heating mode. Meanwhile, the electric heater will be
started up 3 seconds later than the fan.
When Tamb ≥ Tpreset +2 ℉(1 ° C), the electric heating will be turned off, and the fan will continue to run
until Tair discharge ≤ 90 ℉ and the unit is stopped ( the fan will keep run 15 seconds at least). Then the fan
will turn to the status that it stops for 10 minutes and runs for 1 minute at low speed periodically. If Tamb ≤
Tpreset - 2 ℉(1 ° C), the unit will quit the circulation.
When Tpreset -2 ℉(1 ° C) < Tamb < Tpreset +2 ℉(1 ° C), the unit keeps previous running status.
* In this mode, the unit displays the setting temperature and heating LED is illuminated. The setting
temperature range is 55 ~ 80 ℉ (13 ~ 27 ° C).
For heat pump with electric heater units, working conditions and process for heating:
If the room temperature (Tamb) is less than 5° F from set point the compressor will be turned on in the
heating function and run until the room temperature is satisfied.
When Tamb ≤ Tpreset -2 ℉(1 ° C), the unit is running in heating mode. Meanwhile, the compressor will be
started up.
When Tamb ≥ Tpreset +2 ℉(1 ° C), the compressor and the fan will be turned off.
When Tpreset -2 ℉(1 ° C) < Tamb < Tpreset +2 ℉(1 ° C), the unit keeps previous running status.
If the room temperature (Tamb) falls to 5 ° F below the set point temperature (Tpreset) the reverse cycle
heat will be shut off and the electric strip heat is turned on for one cycle until heating set point is satisfied.
* In this mode, the electric strip heaters and the compressor will not operate simultaneously.
The unit displays the setting temperature and heating LED is illuminated. The setting temperature range is

FUNCTION AND CONTROL

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