Manual 2100-487
Page
14 of 23
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.
FIGURE 8
COMPRESSOR CUTOFF THERMOSTAT WIRING
4 - 10KW 1PH --- 6 & 9KW 3-PH
FIGURE 9
COMPRESSOR CUTOFF THERMOSTAT WIRING
15 - 20KW 1-PH & 3-PH
Temperature and Humidity Controller #8403-060, along
with the Outdoor Sensor option Part #8403-061, can be
used to:
• Limit minimum outdoor temperature for cooling option.
• Limit minimum outdoor temperature for heat pump option.
• Inhibit electric heat operation for heat pumps above
selected outdoor temperature.
Thus, not requiring the optional compressor cut-off
thermostat or the electric heat cut-off thermostat option.
OPTIONAL COMPRESSOR CUTOFF
THERMOSTAT (See Figures 8 and 9)
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.
