GENERAL INSTALLATION INFORMATION

Counter

Fireplace

H

W

Figure 1 - Example of a Large Room with 1/2 Wall Divider

The following formula can be used to determine the maximum heater rating per the definition of unconfined space:

BTU/hr =

(L1 + L2) Ft x (W) Ft x (H) Ft.

x 1000 BTU/hr

50

Consider two connecting rooms with an open area between, with the following dimensions:

L1 = 151/2 Ft., L2 = 12 Ft., W = 12 Ft., H = 8 Ft.

BTU/hr =

(151/2 + 12) x (12) x (8)

x 1000 = 52800 BTU/hr

50

 

 

If there were a door between the two rooms the calculation would be based only on the room with the heater.

BTU/hr =

(151/2) x (12) x (8)

x 1000 = 29760

BTU/hr

50

 

 

 

WARNING

If the area in which the heater may be operated is smaller than that defined as an unconfined space or if the building is of unusually tight construction, provide adequate combustion and ventilation air by one of the methods described in the National Fuel Gas Code, ANSI Z223.1/NFPA 54, Section 5.3 or applicable local codes.

86D0024

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Monessen Hearth MJ27NR, MJ27PR operating instructions BTU / hr =