High Altitude Installations; Air Shutter Setting - Majestic MERCURY Series Installation Manual

D. High Altitude Installations
NOTICE: If the heating value of the gas has been reduced,
these rules do not apply. Check with your local gas utility
or authorities having jurisdiction.
When installing above 2000 feet elevation:
• In the USA: Reduce input rate 4% for each 1000 feet
above 2000 feet.
• In CANADA: Input ratings are certified without a reduction
of input rate for elevations up to 4500 feet (1370 m)
above sea level. Please consult provincial and/or
local authorities having jurisdiction for installations at
elevations above 4500 feet (1370 m).
Check with your local gas utility to determine proper
orifice size.
Majestic • MERC32IN, MERC32IL Installation Manual • 2401-980 Rev. L • 1/21
E. Air Shutter Setting
Air shutter settings should be adjusted by a qualified in-
staller at the time of installation. The air shutter is set at
the factory for minimum vertical vent run. Adjust air shut-
ter for longer vertical runs.
NOTICE: If sooting occurs, provide more air by opening
the air shutter.
Air Shutter Settings
Model Gas Type
MERC32IN NG
MERC32IL Propane
Setting
3/16 in.
1/2 in.
49