High Altitude; Conversion Kit Requirements And Manifold Test Pressures - Lennox G71MPP SERIES Unit Information

H− High Altitude
NOTE − In Canada, certification for installations at eleva-
tions over 4500 feet (1372 m) is the jurisdiction of local au-
thorities.
G71MPP units require no manifold pressure adjustments
for operation at altitudes up to 10,000 feet (3048m) above
sea level. Units installed at altitude of 7,501 to 10,000 feet
(2287 to 3048m) require a pressure switch change per
table 42. Table 42 lists conversion kit requirements, pres-
sure switch requirements and manifold pressures at all alti-
tudes.
LP/Propane
Kit
Model
Input
0 − 10,000 0 − 7,500
Size
(0 − 3048 m) (0 − 2286 m)
−070
−090
33W41 Not required
−110
−135
NOTE − Pressure switch is factory set. No adjustment necessary. All models use the factory installed pressure switch from 0−7,500 feet (0− 2286m).
NOTE − See previous page for manifold pressure measurement procedure.

Conversion Kit Requirements and Manifold Test Pressures

High Altitude Pressure
Switch Kit
7,501 − 10,000
(2287 −
3048m)
33W27
40W05
40W06
40W07
NOTE − The values given in table are measurements only.
The gas valve should not be adjusted.
The combustion air pressure switch is factory−set and re-
quires no adjustment.
NOTE − A natural to L.P. propane gas changeover kit is nec-
essary to convert this unit. Refer to the changeover kit
installation instruction for the conversion procedure.
TABLE 42
Manifold Pressure at All Altitudes (in. w.g.)
Low Fire
(40% rate)
Natural Gas LP/Propane
0.7 2.0
Page 50
High Fire
(100% rate)
Natural Gas LP/Propane
3.5 10.0