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5
High Altitude Installations
U.L. Listed gas fireplaces are tested and approved for elevations from 0 to
2,000 feet in the U. S. A. and from 0 to 4,500 feet in Canada.
When installing this fireplace at an elevation above 2,000 feet (in the United
States), it may be necessary to decrease the input rating by changing the
existing burner orifice to a smaller size. Input should be reduced four percent
(4%) for each 1,000 feet above sea level, unless the heating value of the gas
has been reduced, in which case this general rule will not apply. To identify the
proper orifice size, check with the local gas utility.
When installing this fireplace at an elevation between 2,000 and 4,500 feet (in
Canada), the input rating must be reduced by ten percent (10%).
When installing this fireplace at an elevation above 4,500 feet (in Canada),
check with local authorities.
Consult your local gas utility for assistance in determining the proper orifice for
your location.