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31-5000734 Rev. 0
Proper Gas Flow (Approximate)
Furnace should operate at least 5 minutes before checking
gas flow. Determine time in seconds for
two
revolutions of
gas through the meter. (Two revolutions assures a more
accurate time.)
Divide by two
and compare to time in
Table 18 below.
NOTE:
To obtain accurate reading, shut off all other gas
appliances connected to meter.
Unit
Seconds for One Revolution
Natural
1 cu ft Dial
2 cu ft Dial
060
60
120
080
45
90
100
36
72
Natural-1000 btu/cu ft
Table 18. Gas Meter Clocking Chart
High Altitude
Units may be installed at altitudes up to 7,500 ft. above
sea level. See Table 17 for de-rate manifold values. 60K
natural gas units installed at altitude of 4,501 - 7,500 feet
require a pressure switch change, which can be ordered
separately. Table 19 lists pressure switch requirements at
high altitude.
The combustion air pressure switch is factory-set and
requires no adjustment.
Unit
High Altitude Pressure Switch
(4,501 - 7,500 ft)
Natural
060
20K91
080
No Change
100
No Change
Table 19.
