40
If any factory installed wiring must be
replaced, use a minimum 105°C type AWM
insulated conductors.
Thermostat Control Wiring
If a thermostat is used for unit control,
thermostat should be located on an inside
wall 4-5 feet above the floor where it will not
be subjected to drafts, sun exposure, or heat
from electrical fixtures of appliances. Control
wiring must deliver adequate voltage to
components to assure proper operation.
Control voltage returning from controller
circuit must be a minimum of 21 VAC. To
assure proper wiring use the following chart
to determine the allowable wiring distances.
Table 7 - Control Wiring
Wire
Size
(Stranded) - Copper
Conductors Only
Total Wire Distance
Allowable
20 AWG
200 ft
18 AWG
350 ft
16 AWG
500 ft
14 AWG
750 ft
12 AWG
1250 ft
Total Wire Distance Allowable =
(Quantity of Control Wires) x
(Control Wire Distance)
Take the total wire distance allowable and
divide by the number of wires to be
connected. This indicates the distance
allowable for that size wire. The wiring to the
unit must not exceed the total wire distance
allowable. If the voltage at the connectors is
less than 21 VAC, isolation relays must be
installed. If under external control 21 VAC
must be field verified.
All external devices must be powered via a
separate external power supply.
Example:
A total of 8 wires must be pulled 75ft to a
control the unit. What size wire should be
used?
According to the Table 7, 16 AWG allows for
63ft (500 ft/8 wires) and 14 AWG allows for
94ft (750 ft/8 wires). Thus, 14 AWG should
be used.
Gas Heating
Unit Location and Clearances
1. Be sure unit is located with respect to
building construction and other equipment to
provide ready access and clearance to access
panels or doors that must be opened to permit
adjustment and servicing of the heating
module.
2. The heating unit provided is listed for
installation on the positive side of the
circulating air blower only.
3. Locate unit to insure an adequate supply of
fresh air to replace air used in the combustion
and ventilation process.
FOR YOUR SAFETY
Read
the
entire
gas
heating
installation section of this manual
before beginning installation of the
gas heating section.
If you do not follow these instructions
exactly, a fire or explosion may result
causing property damage, personal
injury, or loss of life.
WARNING
