Polar Air PTTW-10-EC+EH Series, Engineering Manual

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THROUGH THE WALL UNIT 24
3. Compressor turns on again after 30 seconds
4. Indoor fan runs under pre-heat control settings. Please refer to 2.2.4.7
Note: Indoor fan will shut off during defrost cycle. The PTC electric heater will remain on.
Please refer to 2.2.6.
2.2.5.3 AUTOMATIC DEFROST FUNCTION
If OPT sensor fails, the unit will select automatic defrost function.
a. Automatic defrost function start condition:
In heating mode, compressor continuously runs for 25 minutes; if IPT-RT ” 64.4 ° F, the unit will
go into defrost function.
b. Automatic defrost function stop condition:
When the compressor has run for 12 minutes, unit will stop defrost function.
2.2.6 PTC ELECTRIC HEATER (For PTTW-10-EC only)
2.2.6.1 Manual PTC electric heater function (manual ON/OFF)
When the unit is under heating mode, press the electric heater power button from on-board
control panel or IR-handset to activate the electric heater functionality (electric heater LED
indicator will light up). Press the same button again to disable the electric heater function.
PTC electric heater turns on when the following conditions are met:
a. Room temperature RT ” 78.8 ° F
b. When RT ” Ts+ 1.8 ° F, PTC is ON after 1 second delay.
When RT
Ї
Ts + 3.6 ° F, PTC is OFF.
c. Indoor coil temperature < 131 ° F
Note: if any of the above conditions are not fulfilled, PTC electric heater will turn off. It will turn
on again when a,b,c conditions are fulfilled.
2.2.6.2 PTC electric heater overheat protection:
When the indoor coil temperature • 131 ° F, electric heater turns off. It turns on again when
indoor coil temperature ” 118.4 ° F.
When the room temperature sensor fails, the electric heater will not work.