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Thermistors
Thermistors
Thermistors provide temperature feedback to the
main board to maintain proper room temperature
and operating conditions of the sealed system.
On heat pump models (AZ65), thermistors also
provide outdoor air temperature and outdoor
coil temperature in order for the main board to
operate the Zoneline by the most efficient means.
Thermistors
: All Zoneline models have two
indoor thermistors which are attached to the
indoor coil. The indoor air thermistor is mounted
on the front of the coil to sample the incoming
room air.
The indoor coil thermistor is mounted on the right
side of the coil in a copper well to sample the coil
temperature.
The outlet air thermistor is mounted on the air
deflector to sample the outgoing air temperature.
Indoor Thermistor Resistance (ohms)
All Zoneline heat-pump models have two indoor
thermistors and two outdoor thermistors.
°F
Air
Coil
10
28030
28030
30
15340
15340
32
14570
14570
50
8850
8850
70
5300
5300
90
3280
3280
Thermistors Indoor
Thermistors Outdoor
Outdoor Thermistors Resistance (ohms)
Features may vary depending model number
throughout this Service Guide.
All Zoneline heat pump models have two outdoor
thermistors.
One outdoor thermistor is attached to the outdoor
coil and the other outdoor thermistor is set into
the base assembly, enabling it to monitor outdoor
air temperature.
°F
AIR
COIL OUTLET
10
63,260
94,900
296,800
30
34,620
51,940
169,800
32
32,860
49,330
161,500
50
19,970
29,960
99,480
70
11,950
17,930
59,700
90
7,320
10,970
36,990
