Goodman Amana AMH8 Service Instructions Manual page 37

PRODUCT DESIGN
COUNTERFLOW FILTER INSTALLATION
This furnace has provisions for the installation of return air
filters at the counterflow top return. The furnace will
accommodate the following filter sizes depending on cabinet
size:
Optional
Access
Door
COUNTERFLOW TOP RETURN
Filter Area
Cabinet
2
Width
(in )
14
17 1/2
600
21
24 1/2
14
17 1/2
800
21
24 1/2
14
17 1/2
1000
21
24 1/2
Refer to Minimum Filter Area tables to determine filter area
requirement. NOTE: Filters can also be installed elsewhere
in the duct system such as a central return.
Horizontal Installations
Filter(s) must be installed external to the furnace cas-
ing for horizontal installations. For most installations it
is preferable to use a central return with filters installed
in the duct behind the return air grill. In this way filter
replacement is relatively simple by merely removing the
grille, rather than going into the attic or crawl space.
ADDITIONAL FILTERING ACCESSORIES
External Filter Rack Kit (EFR01)
The external filter rack kit is intended to provide a lo-
cation external to the furnace casing, for installation of
a permanent filter on upflow model furnaces. The rack
is designed to mount over the indoor blower compart-
ment area of either side panel, and provide filter reten-
tion as well as a location for attaching return air
ductwork.
Return Air
"A"
Min
Filter Size Dimension "A:
Qty.
(in) (in)
15.1
14.2
2 15x20x1
13.0
11.3
20.4
19.7
2 20x20x1
18.8
17.7
25.5
25.0
2 25x20x1
24.3
23.4
NORMAL SEQUENCE OF OPERATION
P U
OWER P
1. 115 VAC power applied to furnace.
2. Integrated ignition control module performs inter-
nal checks.
3. Integrated ignition control module LED will light.
4. Integrated ignition control monitors safety circuits
continuously.
5. Furnace awaits call from thermostat.
H M
EATING ODE
(M DIP
ODE SWITCH IS SET TO
The normal operational sequence in heating mode is as
follows:
• R and W thermostat contacts close, initiating a
call for heat.
• Integrated control module performs safety circuit
checks.
• Induced draft blower is energized for 15 second
pre-purge period causing pressure switch contacts
to close.
• Igniter warm up begins after 15 second prepurge
expires.
• Low and high stage gas valves open at end of ig-
niter warm up period, delivering gas to burners
and establishing flame.
• Integrated control module monitors flame pres-
ence. Gas valve will remain open only if flame is
detected.
• Circulator blower is energized on high heat speed
following a fixed thirty second blower on delay.
Electronic air cleaner terminals are energized with
circulator blower.
• Furnace operates; integrated control module moni-
tors safety circuits continuously.
• R and W thermostat contacts open, completing
the call for heat.
• Gas valve closes, extinguishing flame.
• Induced draft blower is de-energized following a
fifteen second post purge.
• The circulator blower will then run in high heat
speed for the blower off delay period, (either 100
or 150 seconds)
"1 STG" )
POSITION
37