5
Leave approximately 6" of cable extending through the wall
for connection to thermostat. Leave approximately 10" of
cable extending into the 14-1/4" (±1/8") opening for con-
nection at Relay Kit. See A7 Thermostat Location, page
12.
If System if to control a gas furnace:
Route two 18 AWG from the furnace to 14-1/4" (±1/8") open-
ing at this time.
Section A - Installation, cont’d.
FIG. A9
FIG. A10
FIG. A11
In some installations, the OEM supplies their own return
air kits. Sometimes both the return and the discharge air
are ducted to and from the 14-1/4" x 14-1/4" (±1/8") open-
ing. In some cases the bottom of the 14-1/4" x 14-1/4" (±1/
8") opening is covered with ceiling material.
In this type of installation the 14-1/4" x 14-1/4" (±1/8") open-
ing is divided. If the divider only fills to the thickness of the
ceiling cavity, an air gap may be created both on the top
and bottom of the thickness of the roof gasket, roof or ceil-
ing material. A gasket, etc., must be used to fill up the
open space to reduce recirculation. See FIG. A9.
Another method of connecting the discharge air to the
coach’s main duct used Duo-Therm’s return air kit. It uses
half of the 14-1/4" x 14-1/4" (±1/8") opening as a discharge
plenum. If the duct opening is not clean, restriction of air
can cause the coil to freeze. The opening of the duct should
be as large as possible to make the air distribution better in
the coach and reduce freeze-up. See FIG. A10.
The final method of installation dumps the discharge air
directly into the RV’s main duct. The duct is routed through
the 14-1/4" x 14-1/4" (±1/8") opening. A duct adapter is used
to connect the air conditioner to the main duct. If this con-
nection is not made properly, cold air can migrate back into
the return air path and make conditions right for freeze-up.
Be sure the duct adapter is sealed to the main duct and air
conditioner. See FIG. A11.
A6a. Roof Top Units
Manual
Compliments
of
Northwest
RV
Supply
Printed
From
http://www.nwrvsupply.com
