Mr. Heater MH25LP / MH25NG operating instructions Heater Mounting Instructions

•This heater may be mounted on any wall; however, it is recommended that the heater be mounted in the middle of the wall opposite any overhead doors.

•When selecting installation locations for this heater ensure that the opening of any exterior or interior doors or windows will not violate mini- mum clearances or contact any heater compo- nents.

•If an overhead door is installed in the building, verify that the heater is not installed in such a way as to interfere with door operation and verify that the door in its open position will not reduce clearances below the minimum requirements. Never mount the heater in such a way that would position the heater above an opened overhead door.

•In most cases the infiltration around your uninsulated entry doors and windows will provide enough air flow for efficient heater operation.

Unrestricted air flow during heater operation is essential to prevent the area above the installed heater from overheating. If your workshop/utility building is tightly insulated (including windows, doors, openings, etc.) the following ventilating methods must be followed:

•A single exhaust vent is supplied with your heater for your convenience. This vent must be located above the heater (preferably at the highest point in the building interior) and it must vent to the exterior of the building. An additional vent is available from the factory for those having a finished workshop or utility building.

•An intake vent, or equivalent, from the exterior of the building and having an effective area of 75 square inches must be located below the heater (preferably within 2 feet of the building’s floor).

•Openings equivalent to intake vent would be: partially open doors and partially open windows.

•Openings of this size (5 inch by 13 inch, or 3 inch by 25 inch) will prevent dangerous heat buildup above the heater.

Ensure that no gas lines or electrical wiring or conduits will interfere with mounting of the heater to the wall.

Depending on local codes and requirements and the installer’s skill level, the sizing and installation of gas lines required to supply the heater may require the assistance of a professional. If in doubt as to these requirements, discuss the requirements of this manual with the dealer from whom the heater was purchased and your gas supplier, or call our customer service

department at 1-800-251-0001.

The selection of the thermostat mounting location is critical to efficient and effective heater operation.

•The thermostat should be mounted about 5 feet above the floor where air can circulate freely around it.

•The thermostat should not be mounted directly to a cold exterior wall without an insulated mounting block.

•The thermostat should not be mounted in direct drafts.

•The thermostat should not be mounted directly below the installed the heater.

•The thermostat should not be installed at a distance that is farther from the heater than the length of the thermostat cable.

2.HEATER MOUNTING INSTRUCTIONS

After selecting the heater installation location and the thermostat location and after verifying and ensuring that all of the above placement requirements are fulfilled, mount the heater as follows:

A.Determine how you wish to install the vent based on the construction of the building and your personal preference. (i.e., do you wish the flanged (finished) side on the interior or the exterior of the building or do you want two vents so that both exterior and interior will be finished?) If needed, order an additional vent from the factory. Our address and toll free phone number are on the rear cover of this manual. Install the vent as follows:

1.See Figure 3 for dimensions and information on the vent.

2.Select a place as high above the heater as possible in accordance with the above require- ments and ensure that the vent or vents will not contact or interfere with existing building sys- tems (i.e., ducts, wiring, plumbing, etc.)

3.Place the unfinished side of the vent against the wall in its elected location and trace its dimen- sions on the wall with a pencil or other suitable marker.

4.Cut or otherwise open a hole in the wall, or walls for finished buildings, having the dimensions of the unfinished side of the vent.

5.Install the vent or vents as desired and retain with 4 suitable fasteners through the predrilled holes in vent flange.

Model # MH25NG/LP HS25NG/LP 6 Installation instructions and Owner’s Manual