GM9C80/GC9C80 install-specs-accessories

Skylar Kaczanowski

Mar 22, 2025

Product Application

This furnace is primarily designed for residential home-heat- ing applications. It is NOT designed or certified for use in mobile homes, trailers or recreational vehicles. Neither is it designed or certified for outdoor applications. The furnace must be installed indoors (i.e., attic space, crawl space, or garage area provided the garage area is enclosed with an operating door).

This furnace can be used in the following non-industrial commercial applications:

Schools, Office Buildings, Churches, Retail Stores, Nursing Homes, Hotels/Motels, Common or Office Areas

In such applications, the furnace must be installed with the following stipulations:

It must be installed per the installation instructions provided and per local and national codes.
It must be installed indoors in a building constructed on site.
It must be part of a ducted system and not used in a free air delivery application.
It must not be used as a “make-up” air unit.
All other warranty exclusions and restrictions apply.

This furnace may be used as a construction site heater

ONLY if all of the following conditions are met:

The vent system is permanently installed per these installation instructions.
A room thermostat is used to control the furnace. Fixed jumpers that provide continuous heating CANNOT be used and can cause long term equipment damage. Bi-metal thermostats, or any thermostat affected by vibration must not be used during construction.
Return air ducts are provided and sealed to the furnace.
A return air temperature range between 60ºF (16ºC) and 80ºF (27ºC) is maintained.
Air filters are installed in the system and replaced daily

during construction and upon completion of construction.

MERV 11 (Example P/N AMP-11-2025-45) air filter(s) are installed in the system and inspected daily and replaced as needed during construction and upon completion of construction.
The input rate and temperature rise are set per the furnace rating plate.
100% outside air must be used for combustion during construction. Temporary ducting may be used to supply outside air to the furnace for combustion – do not connect this duct directly to the furnace. Size this duct according to NFPA 54/ANSI Z223.1 section for Combustion and Ventilation Air.

The furnace heat exchanger, components, duct system, air filters and evaporator coils are thoroughly cleaned following final construction clean up by a qualified person.

All furnace operating conditions (including ignition,

input rate, temperature rise and venting) are verified by a qualified person according to these installation

instructions.

- Furnace doors must be in place on the furnace while the

furnace is operating in any mode.

- Damage or repairs due to failure to comply with these

requirements are not covered under the warranty.

Location Requirements and Considerations

Your unit model type determines which installation proce- dures must be used. For *M9C80 models, you must follow instructions for Horizontal Left, Horizontal Right or Upflow installations only. These furnaces are not approved for Down- flow installations.

*C9C80 models may be installed in the Downflow position as

well as Horizontal Left & Horizontal Right positions.

Follow the instructions listed below when selecting a furnace location. Refer also to the guidelines provided in the Com- bustion and Ventilation Air Requirements.

Centrally locate the furnace with respect to the proposed

or existing air distribution system.

Ensure the temperature of the return air entering the furnace is between 55°F and 100°F when the furnace is heating.
Provisions must be made for venting combustion products outdoors through a proper venting system. The length of flue pipe could be a limiting factor in locating the furnace.
Ensure adequate combustion air is available for the furnace. Improper or insufficient combustion air can expose building occupants to gas combustion products that could include carbon monoxide. Refer to Combustion and Ventilation Air Requirements section.
The furnace must be level. If the furnace is to be set on a floor that may become wet or damp at times, the furnace should be supported above the floor on a concrete base sized approximately 1-½” larger than the base of the furnace.
Ensure upflow or horizontal furnaces are not installed directly on carpeting, or any other combustible material. The only combustible material allowed is wood.

Gas and Venting:

MODEL

MINIMUM VENT

UPFLOW

COUNTERFLOW

060

4 inch

080

4 inch

100

5 inch

4 inch

INLET GAS SUPPLY PRESSURE

Natural Gas

Minimum: 4.5" w.c.

Maximum: 10.0" w.c.

Propane Gas

Minimum: 11.0" w.c.

Maximum: 13.0" w.c.

MANIFOLD GAS PRESSURE

Gas

Range

Nominal

Natural

3.2 - 3.8" w.c.

3.5" w.c.

Propane

9.7 - 10.3" w.c.

10.0" w.c.

Gas

Altitude

Kit

Orifice

Manifold Pressure

Pressure Switch Change

Natural

0-5500

None

#45

3.5" w.c.

None

Propane

LPM-06

#55

10.0"w.c.

None

Length of Pipe in Feet	Nominal Black Pipe Size
	1/2"	3/4"	1"	1 1/4"	1 1/2"
10	132	278	520	1050	1600
20	92	190	350	730	1100
30	73	152	285	590	980
40	63	130	245	500	760
50	56	115	215	440	670
60	50	105	195	400	610
70	46	96	180	370	560
80	43	90	170	350	530
90	40	84	160	320	490
100	38	79	150	305	460

Sizing Between First and Second Stage Regulator* Maximum Propane Capacities listed are based on 2 psig pressure drop at 10 psig setting. Capacities in 1,000 BTU/hour.
Pipe or Tubing Length, Feet		Tubing Size, O.D. Type L										Nominal Pipe Size Schedule 40
		3/8"		1/2"		5/8"		3/4"		7/8"		1/2"		3/4"
10		730		1,700		3,200		5,300		8,300		3,200		7,500
20		500		1,100		2,200		3,700		5,800		2,200		4,200
30		400		920		2,000		2,900		4,700		1,800		4,000
40		370		850		1,700		2,700		4,100		1,600		3,700
50		330		770		1,500		2,400		3,700		1,500		3,400
60		300		700		1,300		2,200		3,300		1,300		3,100
80		260		610		1,200		1,900		2,900		1,200		2,600
100		220		540		1,000		1,700		2,600		1,000		2,300
125		200		490		900		1,400		2,300		900		2,100
150		190		430		830		1,300		2,100		830		1,900
175		170		400		780		1,200		1,900		770		1,700
200		160		380		730		1,100		1,800		720		1,500
Pipe or Tubing Length, Feet	Tubing Size, O.D. Type L								Nominal Pipe Size Schedule 40
	3/8"		1/2"		5/8"	3/4"	7/8"	1-1/8"	1/2"		3/4"	1"	1-1/4"		1-1/2"
10	39		92		199	329	501	935	275		567	1,071	2,205		3,307
20	26		62		131	216	346	630	189		393	732	1,496		2,299
30	21		50		107	181	277	500	152		315	590	1,212		1,858
40	19		41		90	145	233	427	129		267	504	1,039		1,559
50	18		37		79	131	198	376	114		237	448	910		1,417
60	16		35		72	121	187	340	103		217	409	834		1,275
80	13		29		62	104	155	289	89		185	346	724		1,066
100	11		26		55	90	138	255	78		162	307	630		976
125	10		24		48	81	122	224	69		146	275	567		866
150	9		21		43	72	109	202	63		132	252	511		787
200	8		19		39	66	100	187	54		112	209	439		665
250	8		17		36	60	93	172	48		100	185	390		590

Accessories:

Model

Description

GM9C80 0403A*

GM9C80 0603A*

GM9C80 0603B*

GM9C80 0803B*

GM9C80 0804B*

GM9C80 0804C*

GM9C80 0805C*

GM9C80 0805D*

GM9C80 1004C*

GM9C80 1005C*

GM9C80 1205D*

AFE18-60A

Fossil Fuel (Dual Fuel) Kit

√

HA-02

High-Altitude Natural Gas Kit

√

LPLP03

Low LP Gas Pressure Switch

√

LPM-06

LP Conversion Kits

√

Model

Description

GC9C80
0403A*

GC9C80
0603A*

GC9C80
0603B*

GC9C80
0804B*

AC9C80
0805C*

GC9C80
1005C*

SBT14

Downflow Sub-Base 14"

√

―

SBT17

Downflow Sub-Base 17.5"

―

√

―

SBT21

Downflow Sub-Base 21"

―

√

AFE18-60A

Fossil Fuel (Dual Fuel) Kit

√

HA-02

High-Altitude Natural Gas Kit

√

LPLP03

Low LP Gas Pressure Switch

√

LPM-06

LP Conversion Kits

√