Mr. Heater MHU 80 사용자 설명서

Operating Instructions and Owner’s Manual

Compact Unit / Utility Heater

These units are certified for residential applications. For installation 
in a residential garage, these units must be installed so that 
burners and ignition source are located no less than 18” (457mm) 
above floor. Heater must be located or protected to avoid physical 
damage by vehicles. Refer to CSA B149.1, Natural Gas and Propane 
Installation Code current edition.

In a confined area, the heater must be installed in accordance 
with the CSA B149.1, Natural Gas and Propane Installation Code. 
Be sure to check with local codes and ordinances for additional 
requirements.

Unit is shipped ready for installation. Unit may be installed as 
shown in 

figure 1 or inverted 180

o

 depending on desired location 

as governed by clearances, vent connection, air direction, gas 
supply, electrical supply and service accessibility.

1.  If installing unit in an inverted position: Remove and retain 

screws securing door and rotate door 180

o

. Secure with 

retained screws. Rotate louvers directing airflow as desired.

2.  Choose location for mounting brackets.

3.  Remove and retain three screws along top edge (bottom 

edge when inverted) of front of unit.

4.  Align screw holes on mounting bracket with holes along 

top edge (either upright or inverted) of unit. Secure one 
mounting bracket to front of unit with retained screws. 
Secure other mounting bracket to back of unit with screws 
provided in bag assembly containing flue transition.

5.  To support unit, secure mounting bracket to ceiling joist or 

truss. Unit may also hang on rods as shown in 

figure 1.

Adequate facilities for supplying air for combustion and ventilation 
must be provided in accordance with the latest edition of section 
5.3, Air for Combustion and Ventilation, of the National Fuel 

Gas Code, ANSI Z223.1, in the U.S.A., CSA B149.1 Natural Gas 
and Propane Installation Code, or applicable provisions of local 
building codes.

All gas fired appliances require air to be used for the combustion 
process. In many buildings today, there is a negative indoor air 
pressure caused by exhaust fans, etc. If sufficient quantities of 
combustion air are not available, the heater or another appliance 
will operate in an inefficient manner, resulting in incomplete 
combustion which can result in the production of excessive carbon 
monoxide.

CAUTION Insufficient combustion air can cause headaches, 
nausea, dizziness, asphyxiation or death.

If indoor air is to be used for combustion, it must be free of the 
following substances or the life of the heat exchanger will be 
adversely affected: chlorine, carbon tetrachloride, cleaning solvent, 
halogen refrigerants, acids, cements and glues, printing inks, 
fluorides, paint removers, varnishes, or any other corrosives.

NOTE: The vent is a passageway, vertical or nearly so, used to 
convey flue gases from an appliance, or its vent connector, to the 
outside atmosphere. The vent connector is the pipe or duct that 
connects a fuel-gas burning appliance to a vent or chimney. 

Unit heaters must be vented in compliance with all local codes 
or requirements of the local utility, the current standards of the 
(American) National Fuel Gas Code, ANSI Z223.1 or (Canada) 
CSA B149.1 Natural Gas and Propane Installation Code, and the 
following instructions. 

A metal stamped/extruded transition is supplied with this certified 
unit. It must not be modified or altered and must be installed 
on the outlet of the induced draft blower assembly prior to the 
installation of the vent or vent connector. Failure to comply with 
this requirement will void the certification of the unit by the 
approval agencies. All joints shall be secured with at least two 
corrosion resistant screws. All joints must be checked for gas 
tightness after installation. 

 

No. of 

ft 

m

 

Elbows

 

1 

25 

7.6

 

2 

20 

6.1

 

3 

15 

4.6

 

4 

10 

3.0

 

5 

5 

1.5

Maximum length of vent connector not to exceed 30 ft. (9.1m).