IMPORTANT! Please read all information in this manual thoroughly and become familiar
with the capabilities and use of your appliance before attempting to operate or maintain
this unit.
Pay attention to all safety warnings and any other special notes highlighted in the manual.
Safety markings are used frequently throughout this manual to designate a degree or level
of seriousness and should not be ignored. WARNING indicates a potentially hazardous
situation that if not avoided, could result in personal injury or death.
Keep this literature where you have easy access to it in the future. If a problem occurs,
check the instructions and follow recommendations given. If these suggestions don’t
eliminate your problem, call your servicing contractor. Do not attempt to service this
unit yourself!
Under no circumstances should the appliance owner attempt to install and/or service this
equipment. Some local codes require licensed installation / service personnel for this
type of equipment. Improper service, adjustment, or maintenance may cause explosion,
fire, electrical shock or other hazardous conditions which may result in personal injury
or property damage.
WARNING AVERTISSEMENT
FIRE OR EXPLOSION HAZARD
• Failure to follow safety warnings exactly could
result in serious injury or property damage.
• Installation and service must be performed by
a qualified installer, service agency or the gas
supplier.
• Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any
other appliance.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use
any phone in your building.
• Leave the building immediately.
• Immediately call your gas supplier from a
neighbors phone. Follow the gas suppliers
instructions.
• If you cannot reach your gas supplier, call the
fire department.
RISQUE D’INCENDIE OU D’EXPLOSION
• Le non-respect des avertissements de sécurité
pourrait entraîner des blessures graves ou des
dommages matériels.
• L’installation et l’entretien doivent être effectués
par un installateur qualifié, un organisme de
service ou le fournisseur de gaz.
• Ne pas entreposer ni utiliser de l’essence ni
d’autres vapeurs ou liquides inflammables dans le
voisinage de cet appareil, ni de tout autre appareil.
QUE FAIRE S’IL Y A UNE ODEUR DE GAZ
• Ne tenter d’allumer aucun appareil.
• Ne toucher à aucun interrupteur électrique;
n’utiliser aucun téléphone dans le bâtiment.
• Évacuer l’immeuble immédiatement.
• Appeler immédiatement le fournisseur de gaz en
employant le téléphone d’un voisin. Respecter les
instructions du fournisseur de gaz.
• Si personne ne répond, appeler le service des
incendies.
DO NOT DESTROY. PLEASE READ CAREFULLY & KEEP IN A SAFE PLACE FOR FUTURE REFERENCE.
NE PAS DÉTRUIRE. VEUILLEZ LIRE ATTENTIVEMENT ET CONSERVER EN UN LIEU SÛR POUR RÉFÉRENCE ULTÉRIEURE.
USER’S MANUAL
For Furnaces Installed in: Manufactured Homes, Modular Homes/Buildings, & Manufactured Buildings
MG1 Gas Furnaces
2
TABLE OF CONTENTS
IMPORTANT SAFETY INFORMATION ...................................................................................3
GAS SUPPLY & PIPING ........................................................................................................ 3
COMBUSTION AIR & VENTING SYSTEM ............................................................................4
CLEARANCES TO COMBUSTIBLES ....................................................................................4
SHUTTING DOWN THE FURNACE ...................................................................................... 4
GENERAL INFORMATION ......................................................................................................5
ABOUT THE FURNACE ........................................................................................................5
AIR FILTERS .........................................................................................................................5
THERMOSTAT ......................................................................................................................5
FURNACE IN A SMALL ROOM OR CLOSET .......................................................................5
SOURCES OF CORROSION ................................................................................................5
AIR CONDITIONING ..............................................................................................................5
WARRANTY INFORMATION ................................................................................................5
MAINTENANCE INFORMATION .............................................................................................6
BLOWER & FILTER ............................................................................................................... 6
FURNACE & AIR DUCTS ......................................................................................................6
VENTING SYSTEM ...............................................................................................................6
TROUBLESHOOTING .............................................................................................................6
STARTUP & SHUTDOWN ....................................................................................................... 7
STARTING THE GAS FURNACE .......................................................................................... 7
SHUTTING DOWN THE GAS FURNACE .............................................................................7
FURNACE COMPONENTS .....................................................................................................8
3
• Do not use the area around the unit as a storage area.
This area must be kept clean and clear of loose or exposed
insulation materials. Examine the unit’s area when it is
installed or when insulation is added, since some insulation
materials may be combustible.
GAS SUPPLY & PIPING
WARNING
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use
any phone in your building.
• Leave the building immediately.
• Immediately call your gas supplier from a
neighbors phone. Follow the gas suppliers
instructions.
• If you cannot reach your gas supplier, call the
fire department.
AVERTISSEMENT
QUE FAIRE S’IL Y A UNE ODEUR DE GAZ
• Ne tenter d’allumer aucun appareil.
• Ne toucher à aucun interrupteur électrique;
n’utiliser aucun téléphone dans le bâtiment.
• Évacuer l’immeuble immédiatement.
• Appeler immédiatement le fournisseur de gaz en
employant le téléphone d’un voisin. Respecter
les instructions du fournisseur de gaz.
• Si personne ne répond, appeler le service des
incendies.
WARNING:
All fuel piping and shutoff valves must be installed in
compliance with local codes and utility regulations
by licensed installers. DO NOT attempt to modify,
or tap into existing gas lines yourself. Fire or
explosion may result causing property damage,
personal injury or loss of life. Failure to follow the
safety warnings exactly could result in serious
injury, death or property damage.
WARNING:
The gas furnace was shipped from the factory
equipped to operate on natural gas. Conversion
to LP/propane gas must be performed by a
licensed HVAC technician using a factory supplied
conversion kit. Failure to use the proper conversion
kit can cause fire, explosion, property damage,
carbon monoxide poisoning, personal injury, or
death.
WARNING:
To avoid possible equipment damage, fire, or
personal injury, the following instructions must
be observed regarding unit maintenance and
operational procedures.
WARNING:
PROPOSITION 65 WARNING: This product contains
chemicals known to the state of California to cause
cancer, birth defects or other reproductive harm.
WARNING:
Do not operate this furnace if any part has been
submerged under water. A flood damaged furnace
is extremely dangerous. Attempts to use the furnace
may result in fire or explosion. A qualified service
agency should be contacted to inspect the furnace
and to replace any electrical or control system parts
that have been wet or under water.
AVERTISSEMENT:
Ne pas utiliser fournaise si l’une de ses pièces
a été immergée dans de l’eau. Une fournaise
endommagée par une inondation est extrêmement
dangereuse. Toute tentative d’utiliser la fournaise
peut entraîner un incendie ou une explosion. Il faut
communiquer avec un organisme de service qualifié
pour l’inspection de la fournaise et le remplacement
de toutes pièces électriques ou parties du système
de commande qui ont été mouillées ou immergées.
IMPORTANT NOTE
If the unit needs to be shut down for an extended period
of time, turn off both the gas and electrical power. For
your safety always turn off both the gas and electrical
power before performing service or maintenance on
the furnace. If the gas supply to the unit must be shut
off, refer to the shut down instructions on
page 3.
• To achieve optimum performance and minimize equipment
failure, it is recommended that periodic maintenance be
performed on this unit. Please consult your dealer for
maintenance information and availability of maintenance
contracts.
• The area around the gas furnace (
Figure 2, (page 3))
and the vicinity of any other gas appliances must be kept
clear and free of combustible materials, gasoline, and
other flammable vapors and liquids. Do not store or use
flammable items such as paint, varnish, or strippers in the
vicinity of the unit.
• Familiarize yourself with the controls that shut off the gas
and electrical power to the unit.
IMPORTANT SAFETY INFORMATION
4
CLEARANCES TO COMBUSTIBLES
WARNING:
Do not place combustible materials on or against the
furnace cabinet or vent pipe. The area around the
furnace must be kept clear and free of combustible
materials, gasoline and other flammable vapors
and liquids. A fire or explosion may result causing
property damage, personal injury or loss of life.
Failure to follow the safety warnings exactly could
result in serious injury, death or property damage.
The furnace is designed to have certain clearances to
combustible items such as wood, paper, etc. Some types
of insulation are combustible. If your furnace is installed in
an attic, near unfinished walls, or in other insulated space,
keep area surrounding the furnace free of insulating material.
See
Figure 1, (page 4) below.
SHUTTING DOWN THE FURNACE
If you need to shut down your furnace for service or
maintenance, shut off the fuel valve to the furnace before
shutting off the electrical service. Remove the door panel
from the front of the furnace and turn the fuel valve OFF.
See
Figure 2, (page 4). Additional instructions for shutting
down the furnace can be found on
page 7. If your installation
has a manual gas shutoff valve on the fuel supply pipe, shut
this off, then shut off the electric to the furnace.
This furnace does not have a pilot. It is equipped with an
ignition device which automatically lights the burner. DO
NOT light the burner by hand.
IMPORTANT NOTE:
Should overheating occur or the gas supply fails to shut
off, shut off the gas valve to the furnace before shutting
off the electrical supply!
REMARQUE IMPORTANTE
En cas de surchauffe, ou si l’alimentation de gaz omet de
s’arrêter, fermez le robinet de gaz manuel à la fournaise
avant de couper l’alimentation électrique.
COMBUSTION AIR & VENTING SYSTEM
WARNING:
It is extremely important that the furnace receives
an unobstructed flow of clean, fresh air to properly
burn the fuel gas. If this flow of air is restricted,
the partially burned combustion gases may create
dangerous amounts of carbon monoxide - a
colorless, odorless gas that is a deadly poison
that can cause personal injury or death. This could
create the production of excessive amounts of
Carbon Monoxide - a colorless, odorless gas that
is a deadly poison that could result in serious
personal injury or death.
Do not block any openings that are supplying fresh
air to the room or closet the furnace is in. Your
furnace obtains its air through a chase under the
home to the outdoors. Do not allow the inlet of the
chase to become blocked.
• For proper and safe operation, this furnace requires
unrestricted airflow for combustion and ventilation. Do not
block or obstruct air openings on the furnace, air openings
around the furnace area or the spacings around the furnace.
• Do not install home skirting that prevents adequate
combustion air from reaching the furnace.
• Air openings on the top or front of the furnace and openings
in closet doors or walls must never be restricted. If the
furnace is operated without adequate air for combustion,
the flame roll-out switch will open, turning off the gas supply
to the burner. This indicates that a serious problem with the
burners has occurred and must be corrected immediately.
Only a licensed HVAC technician can reset this switch.
• Your furnace and its venting system should be inspected
annually by a licensed HVAC technician. The filter should
be inspected at least once a month. See the Maintenance
Information on
page 6.
IMPORTANT SAFETY INFORMATION-CONTINUED
Figure 1. Minimum Clearances
CLOSET ALCOVE
Front 6” 18”
Back 0” 0”
Sides 0” 0”
Roof Jack 0” 0”
Top 6” 6”
Top and Sides of Duct 0” 0”
Bottom of Duct — —
A Cabinet (w/ coil box) 0” 0”
A Cabinet (w/o coil box) 1/4” 1/4”
B Cabinet 0” 0”
LEFT
SIDE
FRONT
RIGHT
SIDE
REAR
C
5
ABOUT THE FURNACE
• This furnace has been tested for capacity and efficiency
in accordance with AHRI Standards and will provide
many years of safe and dependable comfort, providing
it is properly installed and maintained. With regular
maintenance, this unit will operate satisfactorily year after
year. Abuse, improper use, and/or improper maintenance
can shorten the life of the appliance and create unsafe
hazards.
• Your furnace is designed to fulfill the requirements of
being classified as a Category I (Catégorie I )furnace.
This classification is related to the furnace’s Annual Fuel
Utilization Efficiency (AFUE) rating, the percentage of fuel
that is converted into usable heating energy.
AIR FILTERS
WARNING:
Never operate the furnace without an air filter in
place. Accumulating dust in the return air can build
up on internal components, resulting in loss of
efficiency, equipment damage, and possible fire.
• An air filter is supplied with the furnace as shipped from
the factory.
• The furnace should always have a clean filter. If the filter
becomes dirty, it should be cleaned or replaced. The filter
is installed over the return air grille of the door inside the
furnace cabinet.
THERMOSTAT
• This single stage gas furnace is designed to be controlled
by a conventional single stage thermostat commonly
available at your local building supply store.
• The thermostat’s wiring must comply with the current
provisions of the NEC (ANSI/NFPA 70) and with applicable
local codes having jurisdiction. Thermostat connections
should be made according to the instructions supplied
with the thermostat and the indoor equipment.
• The thermostat should be mounted about 5 feet above the
floor on an inside wall and not on an outside wall or other
location where its operation may be adversely affected by
radiant heat from fireplaces, sunlight, or lighting fixtures,
and convective heat from warm air registers or electrical
appliances.
• Thermostat styles vary. Please refer to the thermostat
manufacturer’s User Manual for detailed programming
instructions.
FURNACE IN A SMALL ROOM OR CLOSET
If a furnace is installed in relatively small utility room or closet,
the installation needs openings in the walls or door to let return
air in. Make sure that these openings remain unobstructed.
Do not modify these openings in any way without consulting
a licensed HVAC technician.
SOURCES OF CORROSION
It is known that certain common household chemicals can
cause heat exchanger corrosion if the vapors are pulled into
the furnace’s burners The following is a list of chemicals that
should not be used or stored near the furnace.
Do not store these chemicals near the furnace:
• Gasoline/Kerosene
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine based swimming pool chemicals
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents (perchloroethylene)
• Printing inks, paint removers, varnishes, etc.
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners
• Masonry acid washing materials
AIR CONDITIONING
This equipment is UL Listed, and C.S.A. and ARI certified.
An energy-saving air conditioner is available that has been
designed specifically for manufactured housing applications
and can best handle your home comfort needs. Ask your
dealer or contractor about add-on central air conditioning
systems. Ask your dealer, contractor or distributor about
energy-efficient, money saving, split system unit designed
for use with this furnace that will take care of your total
comfort needs.
WARRANTY INFORMATION
A warranty certificate with full details is included with the
equipment. Carefully review these responsibilities with your
dealer or service company. The manufacturer will not be
responsible for any costs found necessary to correct problems
due to improper setup, improper installation, adjustments,
improper operating procedure on the part of the user.
CAUTION:
Operating a gas furnaces in construction
environments can cause a variety of problems
within the furnace and may significantly reduce the
life or the performance of the furnace. Therefore
operating the furnace during construction is not
permitted and will void the warranty.
Some specific examples of service calls which are not included
in the limited warranty are:
• Correcting wiring problems in the electrical circuit supplying
the equipment.
• Resetting circuit breakers or other switches.
• Adjusting or calibrating of thermostat.
GENERAL INFORMATION
6
Proper maintenance is important to achieve optimum performance from the furnace. This equipment should be inspected
annually by a licensed HVAC technician.
Table 1, (page 6) contains suggested inspections and frequency of maintenance.
Routine maintenance should include the following:
BLOWER & FILTER
• Never operate the furnace without a filter in place. Dust
and lint can build up on internal components, resulting in
loss of efficiency, equipment damage, and possible fire.
• Keep air filters cleaned. Filters should be changed or
cleaned monthly during the heating/cooling season.
Clean or replace filter to maintain proper airflow and
achieve maximum efficiency. Filters designed to remove
smaller particles such as pollen, may require additional
maintenance.
• It is recommended that the blower compartment be cleaned
of dirt or lint that may have accumulated in the compartment
or on the blower and motor as part of the annual inspection.
FURNACE & AIR DUCTS
• Homeowners should perform frequent visual inspections of
the furnace for obvious signs of deterioration. The furnace
should be sound without sagging, cracks, gaps, etc around
the base. Any signs of damage or loose connections should
be repaired by a qualified HVAC technician.
• Furniture and drapery should be arranged so that the
supply air registers and return grilles are not obstructed.
VENTING SYSTEM
• For proper and safe operation, the furnace needs air for
combustion and ventilation. Do Not block or obstruct air
openings on the furnace, or any air openings where the
furnace may be installed, including any surrounding spaces.
• Direct vent furnaces pull combustion air from the outdoors
and vent combustion products back outside. Combustion air
coming from the outside needs to be clean of chemicals that
can cause corrosion, such as pool chlorinating products.
• Vent pipe must slope upwards and be physically sound
without holes or corrosion. Any corroded section of vent
pipe must be replaced, and any obstruction or blockage
must be removed by a licensed HVAC technician.
• Flue passageways, the vent system, and the burners should
be inspected and cleaned (if required) by a licensed HVAC
technician annually to ensure continued safe operation.
MAINTENANCE INFORMATION
If the furnace fails to operate check the following:
1. Is the thermostat setting correct?
2. Is the On / OFF switch (inside the blower compartment)
turned on? See Figure 3, (page 6).
3. Is the circuit breaker tripped?
4. Is the fuel manual shutoff turned on?
5. Is the filter dirty or clogged?
If the furnace still doesn’t operate, contact a licensed HVAC
technician.
TROUBLESHOOTING
7
STARTING THE GAS FURNACE
The component you need to familiarize yourself with is the
gas valve. You will use this to turn the furnace on and off
when needed. There are no user serviceable parts. All repairs
must be performed by a licensed HVAC technician.
1. Make sure the filter is clean and properly installed.
2. Make sure the vent system is properly installed.
3. Set the thermostat to the lowest setting.
4. Close the manual gas valve outside the furnace.
5. Turn off all electric to the furnace.
6. Remove the door from the burner compartment.
7. Set the gas valve ON/OFF knob / switch to the OFF
position. See Figure 2 for gas valve type and knob /
switch location.
8. Wait 5 minutes. If there is any smell of gas, see WHAT
TO DO IF YOU SMELL GAS on page 7.
9. Set the gas valve ON/OFF knob to the ON position.
10. Turn on all electric to the furnace, including the ON/
OFF switch.
11. Open the manual gas valve.
12. Turn the thermostat back up to force ignition.
13. Observe operation, including burners. If burners fail
to ignite, call a licensed HVAC technician.
14. Replace the door on the burner compartment.
STARTUP & SHUTDOWN
SHUTTING DOWN THE GAS FURNACE
If you need to shut down your furnace for service or
maintenance, follow these steps:
1. Set the thermostat to the lowest setting.
2. Close the manual gas valve outside the furnace.
3. Turn electric to the furnace off.
4. Open the door to the burner compartment.
5. Set the gas valve ON/OFF knob / switch to the OFF
position. See Figure 3 or Figure 4 for gas valve type
and knob / switch location.
6. Set the ON / OFF switch to off.
7. Replace the door on the burner Compartment.
Table 1. Maintenance Table
MAINTENANCE ITEM
FREQUENCY OF MAINTENANCE
BEGINNING OF
EACH HEATING
SEASON
END OF EACH
HEATING
SEASON
MONTHLY
Verify furnace area is free of combustible materials. X X X
Verify combustion and ventilation air is not restricted. X X X
Verify no signs of physical deterioration of the furnace. X X X
Verify no obstructions or restrictions in vent or chimney. X X —
Verify no holes or cracks in vent pipe. X X —
Verify no corrosion in vent pipe. X X —
Verify the horizontal vent pipes slope upwards away from the furnace. X X —
Clean or replace all filters. — — X
MAINTENANCE ITEMS BELOW SHOULD BE PERFOMED BY QUALIFIED SERVICE PERSONNEL.
Verify burner flame. X — —
Clean blower compartment. X — —
Clean burner assembly. X — —
Reset the nozzle/drawer assembly to factory specifications X — —
Clean the inside of the furnace heat exchanger and replace the combustion liner if necessary. X — —
Adjust the burner for top efficiency and check to make sure all fittings are leak-tight X — —
The furnace components shown in Figure 2 will help identify and locate various parts of the furnace. The component
you need to familiarize yourself with is the gas valve. You will use this to turn the furnace on and off. There are no user
serviceable parts. All repairs must be done by a licensed HVAC technician.
10349150
(Replaces 10284940)
Specifications & illustrations subject to change without notice or incurring obligations (12/20).
O’Fallon, MO, © Nortek Global HVAC LLC 2020. All Rights Reserved.
FURNACE COMPONENTS
Figure 3. Honeywell Gas Valve
ON / OFF Knob
OFF Position
ON Position
ON
OFF
Figure 2. MG1 Gas Furnace Components
Furnace
On-Off
Switch
Gas
Valve
On-Off
Knob
-
1
-
2
-
3
-
4
-
5
-
6
-
7
-
8
