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GENERAL INSTALLATION INFORMATION
Figure 3 - Sample Room for Determining the Maximum Heater Rating
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 |
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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 | ||
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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, 1992, Section 5.3 or applicable local codes.
10 | 33D4047 |