Allied A80US2V - Page 29

508155-01 Issue 2108 Page 29 of 49
Proper Gas Flow (Approximate)
Furnace should operate at least 5 minutes before checking
gas ow. 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
16. If manifold pressure matches Table 20 and rate is
incorrect, check gas orices for proper size and restriction.
NOTE: To obtain accurate reading, shut o all other gas
appliances connected to meter.
Model
Seconds for One Revolution
Natural LP
1 cu ft
Dial
2 cu ft
Dial
1 cu ft
Dial
2 cu ft
Dial
-070 55 110 136 272
-090 41 82 102 204
-110 33 66 82 164
-135 27 54 68 136
Natural - 1000 btu/cu ft LP - 2500 btu/cu ft
Table 16. Gas Meter Clocking Chart
For safety, shut unit o󰀨 and remove manometer as soon
as an accurate reading has been obtained. Take care to
replace pressure tap plug.
IMPORTANT
Proper Combustion
Furnace should operate minimum 15 minutes with correct
manifold pressure and gas ow rate before checking
combustion. Take combustion sample beyond the ue
outlet and compare to Table 17. The maximum carbon
monoxide reading should not exceed 100 ppm.
Model CO
2
% for Nat CO
2
% for LP
High Fire 6.8 - 7.4 7.5 - 9.0
-070 4.2 - 5.7 5.0 - 6.0
The maximum carbon monoxide reading should not exceed
100ppm.
Table 17.
High Altitude
The manifold pressure, gas orice and pressure switch
may require adjustment or replacement to ensure proper
operation at higher altitudes. See Table 20 for manifold
pressures. See Table 19 for gas conversion and Table 18
for pressure switch kits.
Unit
Input
High Altitude Pressure Switch Kit
0 - 4500 ft. 4501 - 7500 ft. 7501 - 10,000 ft.
070 No Change No Change 73W35
090 No Change 69W56 73W35
110 No Change 69W56 73W35
135 No Change 73W33 73W34
Table 18. High Altitude Pressure Switch Kits
Unit
Input
High Altitude
Natural Gas
Orice Kit
Natural Gas to LP/ Propane
Kit
7501 - 10,000
ft.
0 - 7500 ft.
7501 - 10,000
ft.
070 51W01 11K48 11K47
090 51W01 11K48 11K47
110 51W01 11K48 11K47
135 51W01 11K48 11K47
Table 19. White Rodgers Gas Valve Conversion Kits