Manual
2100-423C
Page
13 of 21
FIGURE 8 – COMPRESSOR CUTOFF THERMOSTAT WIRING
4 & 8 KW 1 Phase – 6 KW 3 Phase
WIRING – LOW VOLTAGE WIRING
230/208V, 1 phase and 3 phase equipment dual primary
voltage transformers. All equipment leaves the factory
wired on 240V tap. For 208V operation, reconnect from
240V to 208V tap. The acceptable operating voltage
range for the 240 and 208V taps are:
TAP
RANGE
240
253 - 216
208
220 - 187
NOTE: The voltage should be measured at the field power
connection point in the unit and while the unit is
operating at full load (maximum amperage
operating condition).
Ten (10) wires should be run from thermostat subbase to
the 24V terminal board in the unit. A nine conductor,
18 gauge copper, color-coded thermostat cable is
recommended. The connection points are shown in
Figure 7.
TABLE 3
THERMOSTAT WIRE SIZE
r
e
m
r
o
f
s
n
a
r
T
A
V
A
L
F
e
g
u
a
G
e
r
i
W
m
u
m
i
x
a
M
e
c
n
a
t
s
i
D
t
e
e
F
n
I
5
5
3
.
2
e
g
u
a
g
0
2
e
g
u
a
g
8
1
e
g
u
a
g
6
1
e
g
u
a
g
4
1
e
g
u
a
g
2
1
5
4
0
6
0
0
1
0
6
1
0
5
2
OPTIONAL OUTDOOR THERMOSTAT
APPLICATIONS
Since most equipment at the time of manufacture is not
designated for any specific destination of the country
and are installed in areas not approaching the lower
outdoor temperature range, outdoor thermostats are not
factory installed as standard equipment, but are offered
as an option. There are also different applications for
applying outdoor thermostats. The set point of either
type of outdoor thermostat application is variable with
geographic region and sizing of the heating equipment
to the individual structure. Utilization of the heating
Application Data, and the heat loss calculation of the
building are useful in determining the correct set points.
NOTE: The additional LAB (low ambient bypass) relay
is required to prevent heater operation during low
temperature cooling operation.
OPTIONAL COMPRESSOR CUTOFF
THERMOSTAT (See Figure 8)
Heat pump compressor operation at outdoor
temperatures below 0°F are neither desirable nor
advantageous in term of efficiency. An outdoor
thermostat can be applied to take the mechanical heating
(compressor) off line, and send the (compressor) signal
to energize electric heat in its place (to make electric
heat first stage heating). This can also be applied to
bank the quantity of available electric heat. For
example: A heat pump operates with 10KW second
stage heat – once the outdoor thermostat has switched
then operates 15KW without the compressor as first
stage heat.
