Atwood AFSAD12, Техническое руководство по установке

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*Note the table is for minimum requirements and should in most cases
allow the unit to operate correctly. If unit burner cycles on and off on
high temperature limit extra ducting can be used to help correct this
condition due to restriction or bends in duct work.

Proper duct installation is critical to proper operation of the
furnace. When installing ducts, materials must be rated for
continuous use at 200°F.

Each 4-inch duct opening provides 12 in
2
of discharge area. The
minimum for this furnace is 24 in
2
. If closeable registers or 2”
ducts are used additional ductwork or a front grill system is
required.

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.

Do NOT install heat
register’s closer than 24” to return air system.
FLEXIBLE DUCTING SYSTEMS

Follow ducting configuration given

Avoid sharp bends, deep sags or crushed ducts.

Stretch all ducts thoroughly and run them directly to outlets,
keeping number of angles of bends to a minimum.

Remove knockout plate from desired outlets. If a knockout is
removed accidently cover plates can be purchased.

Unused knockouts MUST be covered.

Attach a duct adapter by inserting flange over casing hole, locking
the tab into casing slot and turning adapter 90°

Attach and secure four-inch flexible duct to adapter(s)

Run duct(s) to desired location within RV, secure to register(s)
AIR FLOW CHECK

Appliance is tested to a temperature rise as specified on the
Rating Plate. After installation of the furnace and duct system is
completed, adjustment to obtain a temperature rise should be
made.

The table below is a reference to maintain maximum operation of
the appliance when checking temperature rise is not possible.

Airflow measurements made at each register, the total reading
should not be less than what is shown in the table below for each
BTU size.

If readings are below the table values airflow can be improved by
adding ducts or by reducing restrictions in the system.
AFSA12 AFS12 AFS16 AFS20
Not Required 1650 FPM 1650 FPM 1800 FPM
*total FPM= feet per minute
FURNACE INSTALLATION

Remove furnace from box

Remove vent assembly supplied with furnace

DO NOT mix assemblies with other units, each model has a
specific vent baffle size to operate correctly, see sticker on vent
assembly.

Remove knockouts in locations that will be used and install
adapters.

The furnace should always be installed level (front to back, side to
side) to prevent water build up into the interior of the vent area.

Units can be installed with or without the interior grill. If grill is not
used a minimum of 35 in
2
. of free return air must be provided.

If units are installed using the small outside vent system, access
to the inside of the coach must be provided directly in front of the
unit to remove for servicing suggested opening size 12-
1/2” wide
by 8-
3/8” height.

Secure unit with two brackets and screws provided at the rear of
the unit through holes provided.

Attach flexible ducting over duct adapters and secure.

Run ducting to locations keeping bends and excess ducting to a
minimum and secure to registers.

Connect wiring to furnace see wiring connection section.

Connect gas line see gas connection section.
SIDEWALL CUTOUT
Maximum exterio
r wall thickness 0” to 2-1/2”. Optional vent kit can be
purchased to extend the vent to a
3” wall thickness only on small vent
installations.
WALL CUTOUTS
Standard Door square corners for proper sealing.
Venting Option A B
D
Small Vent (exterior) - -
3-1/2
”
Dia. Max
Standard Door (exterior) 12-1/2
” Max
7-1/2
”
Max
Front Grill (interior cabinet)
11-
0”
Max
7-
1/4”
Max
Front Grill Trim Ring (interior
cabinet)
12-
1/2”
Max
8-
3/4”
Max

DO NOT oversize hole
– over sizing can result in water leakage.

Zero clearance around air intake cutout for best sealing condition.
SMALL VENT INSTALLATION