Resistance Heaters
The heaters consist of three 265 VAC or 230/208 VAC resistance heating coils fastened together in a
single assembly. The heaters are located behind the indoor coil and are protected against overheating
by 2 thermal protectors. An L185-30 thermal protector is used as a temperature regulator. A one-shot
L248 thermal protector is used as a backup in case the temperature regulating thermal protector fails
(stuck closed).
Heat Pump models will utilize electric resistance heat upon initial heat mode startup or when a power
outage has occurred with the unit in heat mode. The electric heaters will be energized until the room
temperature reaches the thermostat setting. Once the thermostat temperature setting is attained, the
unit will cycle off and automatically switch over to heat pump operation. The heat pump will provide all
heating requirements for subsequent cycles unless one of the following conditions occur:
•
The dip switch has been placed in the I2R (ALL ELECTRIC HEAT) position. When the dip switch is
placed in the up position, heat pump operation will be locked out. Only electric resistance heat will
be available.
•
A temperature differential of approximately 2 °F (temperature differential varies by thermostat
manufacturer) is detected between the thermostat set point and the room air temperature. If a
differential of approximately 2 °F is detected, due to thermostat adjustment or falling room air
temperature, the electric heaters will be energized (heat pump off) until the thermostat is satisfied.
Once the thermostat has been satisfied, the unit will automatically revert back to heat pump
operation for subsequent cycles.
•
The outdoor temperature falls below 25 °F. If the outdoor temperature falls below 25 °F, the unit will
automatically switch from heat pump operation to resistance heat operation. A 7 °F hysteresis loop
will be in effect; therefore, the unit will operate in resistance heat mode until an outdoor temperature
of 32 °F or higher is detected.
Electric resistance heat and heat pump operation will never occur at the same time.
Models without heat pump feature will meet heating requirements by use of electric resistance heating
coils.
5
4
3
2
1
230/208
VAC
BL
WH
GR
RD
GY
BR
BK
BK
WH
RD
BK
RY102
CN2
RY103
PROTECTOR
PR
O
TECT
OR
LO
WER
HEATER
CONN
RD
MIDDLE
UPPER
HEA
TER UNIT
DRIVER
BOARD
MAIN
BOARD
9
8
7
6
1
3
2
1
3
2
2
3
2
3
2
3
GEA01253
Tandem
15 Amp.
Tandem
15 Amp.
Perpendicular
20 Amp.
Perpendicular
20 Amp.
Large Tandem
30 Amp.
Large Tandem
30 Amp.
9
8
7
6
5
4
3
2
1
BK
BK
WH
WH
GY
GY
RD
RD
GR
GR
9
8
7
6
5
4
3
2
1
BK
BK
WH
WH
GY
GY
RD
RD
GR
GR
9
8
7
6
5
4
3
2
1
BK
BK
WH
WH
GY
GY
BL
BL
RD
RD
GR
GR
s
e
u
l
a
V
e
c
n
a
t
s
i
s
e
R
r
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t
a
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r
o
t
c
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n
n
o
c
t
a
d
e
k
c
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h
c
n
e
h
W
r
e
t
a
e
h
t
a
d
e
k
c
e
h
c
n
e
h
W
o
t
k
c
a
l
B
e
ti
h
W
0
2
:
C
A
V
5
6
2
Ω
6
1
:
C
A
V
8
0
2
/
0
3
2
Ω
li
o
C
r
e
p
p
U
9
2
:
C
A
V
5
6
2
Ω
0
2
:
C
A
V
8
0
2
/
0
3
2
Ω
o
t
k
c
a
l
B
d
e
R
8
2
:
C
A
V
5
6
2
Ω
1
2
:
C
A
V
8
0
2
/
0
3
2
Ω
e
l
d
d
i
M
li
o
C
5
4
:
C
A
V
5
6
2
Ω
1
3
:
C
A
V
8
0
2
/
0
3
2
Ω
li
o
C
r
e
w
o
L
0
7
:
C
A
V
5
6
2
Ω
8
4
:
C
A
V
8
0
2
/
0
3
2
Ω
Summary of Contents for AZ75E09DAC
Page 7: ... 5 Direct Connection 208 VAC 230 VAC 265 VAC ...
Page 37: ... 35 Notes ...
Page 45: ... 43 Parts List ...
Page 46: ... 44 ...
Page 47: ... 45 ...
Page 48: ... 46 ...
Page 55: ... 53 Notes ...
