Flexible Ducting Systems; Propane Gas Connection; Electrical Connections - Atwood AFSAD12111 Instruction Manual


Proper duct installation is critical to operation of furnace. When
installing ducts, use materials rated for continuous use at 200°F.

See minimum clearance to floorboards, walls & similar combustible
building materials.

Each 4-inch duct opening provides 12 in
2 . If closeable registers or a 2" duct is used unit
for this furnace is 24 in
must be provide with a front grill system.

Ducting in dead air space with no return air, such as holding tank
areas, does not count toward achieving minimum discharge
requirements.

Adjust ducting installation to obtain air rise of 100°F-130°F for optimum
performance.

FLEXIBLE DUCTING SYSTEMS

When designing flexible duct systems:

Follow ducting configuration show in Table 2.

Avoid sharp bends or crushed ducts.

Stretch all ducts and run them directly to outlets, keeping quantity and
angles of bends to a minimum.
Remove knockout plate from desired outlets. See Figure 6. If both 4"
1.
outlets are not being used leave in place, if removed a cover plate can
be purchased.
2. Attach a duct adapter by inserting flange over casing hole, locking the
tab into casing slot and turning adapter 90°.
3. Attach and secure four-inch flexible duct to adapter(s).
4. Run duct(s) to desired location within RV, secure to register(s).
AIR FLOW CHECK
Appliances are tested to a temperature rise as specified on the Rating
Plate. After installation of the furnace and duct system is completed,
adjustments to be made to obtain a temperature rise as specified on
the Rating Plate.
The table below is used as reference to maintain maximum operation
of the appliance. If checking temperature rise is not possible, air flow
measurements at each registers added together and divide by total
registers will give you air flow reading. This reading should not be less
than the minimum in the table under your BTU appliance size.
If readings are below table values, air flow can be improved by adding
ductwork. Check to make sure restrictions in the system are not
present.
12,000
1650*
*FPM= feet per minute reading
FIRE OR EXPLOSION
Never check for leaks with an open flame. Turn on the gas and apply
soapy water to all joints to see if bubbles are formed.
Figure 6
2
of discharge area. Minimum
16,000 20,000
1650* 1800*
WARNING

PROPANE GAS CONNECTION

Propane Gas Pressure Test
The furnace and any individual shut-off valve must be
disconnected from gas supply piping system during and
pressure testing of system at test pressures of more than 1//2"
PSI.
Before furnace is, connected piping systems are to be tested to
be leak free. The test must maintain air pressure of a least 6"
of mercury or 3 PSI for at least 10 minutes.
The entire piping system is to be maintained for a pressure of
10" to 13" W.C. when all appliances are in operation. Test gas
connections for leakage with soapy water or a leak test
solution.
1. Connect gas line to the fitting located on top right side of furnace or if is
supplied with an extended manifold at the rear of the furnace.
2. Be sure all male pipe threads, other than flare fittings, are treated with
a sealing compound resistant to the action of propane (LP) gas. DO
NOT put sealing compound on flare fittings.
3. Use two wrenches to hold nut when tightening gas lines. DO NOT twist
valve assembly. See Figure 7.

A 1/8" N.P.T. plug is accessible for test gauge connection on gas valve
assembly for pressure testing.

A 3/8" flared fitting connection provided at gas control valve inlet for
gas supply connection to furnace. The gas supply line of the furnace
must be of adequate size to provide 11" W.C. gas pressure. This
pressure to be maintained under maximum flow conditions with all gas
appliances in operation.

If local codes allow the use of a flexible gas appliance connector,
always use a new listed connector. Do not use a connector, which has
previously serviced another gas appliance.
1. Remove grommet plug from furnace.
2. Insert gas line through grommet plug (DO NOT CUT).
3. Connect gas line inside furnace casing immediately ahead of gas
control valve.
4. Connect gas line to brass fitting located on top or right side of
furnace.
5. Some models will have fittings at the rear outside of the casing.
6. Use two wrenches to hold brass fitting and flare nut when
tightening gas line to brass fitting. DO NOT twist valve assembly

ELECTRICAL CONNECTIONS

INJURY OR PROPERTY DAMAGE
 Label all wires before disconnecting for servicing. Wiring errors can
cause improper and dangerous operation. Verify proper operation
after servicing.
 Disconnect electrical power before servicing.
PROPERTY DAMAGE
This connection is for low-voltage battery or direct current only. Do not
connect to 120 or 240 volts AC.
5
Figure 7
WARNING
CAUTION