Heating System Service Checks - Lennox G32V Series Service Literature

12− If the appliance will not operate, follow the instructions
To Turn Off Gas To Unit" and call your service techni-
cian or gas supplier.
Turning Off Gas To Unit
1 − Set thermostat to lowest setting.
2 − Turn off all electrical power to unit if service is to be per-
formed.
3 − Remove access panel.
4 − WhiteRodgers natural valve, move lever to OFF. White-
Rodgers propane and Honeywell valve, turn knob to
OFF. Do not force.
5 − Replace access panel.
NOTE−On initial start−ups and when condensate trap is
dry, unit may turn itself off and on to allow condensate
trap to fill. This is normal operation.
C−Safety or Emergency Shutdown
Turn off unit power. Close manual and main gas valves.
D−Extended Period Shutdown
Turn off thermostat or set to UNOCCUPIED" mode. Close
all gas valves (both internal and external to unit) to guaran-
tee no gas leak into combustion chamber. Turn off power to
unit. All access panels, covers and vent caps must be in
place and secured.
Refer to Maintenance" section of this manual for instruc-
tions on how to prepare condensate assembly for extended
period shutdown.
IV−HEATING SYSTEM SERVICE CHECKS
A−A.G.A./C.G.A. Certification
All units are A.G.A. and C.G.A. design certified without mod-
ifications. Refer to the G32V Operation and Installation In-
struction Manual Information.
2
B−Exhaust CO and CO content
Carbon Dioxide is a colorless and odorless gas produced in
small amounts by all furnaces, including the G32V, during
combustion process. See table 31 or 32 for CO
when the unit is properly installed and operating normally. If
unit appears to be operating normally at or beyond the up-
2
per limit of the CO range, the unit should be checked for
abnormally high CO.
CO content will be less than 0.04% (400 PPM) in an air free
sample regardless of the firing rate used.
TABLE 31
Natural Gas
Hi Fire CO
G32VUnit G32VUnit
Min Vent Max Vent
75,000 7.4−8.4
100,000 6.9−7.9
125,000 6.9−7.9
2
2
Low Fire CO
Min Vent Max Vent
7.8−8.8 5.0−6.0 5.4−6.4
7.3−8.3 4.5−5.5 5.6−6.0
7.7−8.7 5.0−6.0 54.−6.4
G32VUnit G32VUnit
Min Vent
75,000
100,000
125,000
Testing for abnormally high CO
One method for testing the CO
2
ach CO test with the Fyrite CO
2
of testing CO
tions included in the test kit you choose. Follow the proce-
dure below in order to check CO
1 − Drill size "R" or 11/32 in. on the exhaust vent, just exit-
ing the cabinet and tap 1/8−27 NPT. This hole will be
used to draw your CO
2 − Install a hose barb connector into test hole.
3 − Attach one end of Fyrite sampling tube to hose barb.
4 − Set thermostat to highest setting and allow unit to run
15 minutes.
5 − When CO
move hose barb from exhaust vent and use a1/8" plas-
tic plug (46F4801) to close off port.
C−Gas Piping
Gas supply piping should not allow more than 0.5"W.C. drop
in pressure between gas meter and unit. Supply gas pipe
must not be smaller than unit gas connection.
D−Testing Gas Piping
When pressure testing gas lines, the gas valve must be dis-
connected and isolated. Gas valves can be damaged if
subjected to more than 0.5psig (14" W.C.). See figure 51. If
the pressure is equal to or less than 0.5psig (14"W.C.), use
the manual shut−off valve before pressure testing to isolate
furnace from gas supply.
GAS PIPING TEST PROCEDURE (TYPICAL)
MANUAL MAIN SHUT−OFF
VALVE WILL NOT HOLD
NORMAL TEST PRESSURE
levels
CAP
GAS VALVE WILL NOT HOLD TEST PRESSURE IN
EXCESS OF 0.5 PSIG (14"W.C.)
2
In case emergency shutdown is required, turn off
the main shut-off valve and disconnect the main
power to unit. These controls should be properly
labeled by the installer.
Page 47
TABLE 32
Propane Gas
2
Hi Fire CO
Max Vent Min Vent
7.5−8.5 8.2−9.2 5.5−6.5
8.0−9.0 8.5−9.5 5.2−6.2
7.9−8.9 8.4−9.4 5.3−6.3
2
/CO content is the Bachar-
2
indicator. Other methods
/CO are available. Closely follow the instruc-
2
/CO on the G32V furnace.
2
/CO sample.
2
/CO testing is complete, turn off unit, re-
FURNACE
ISOLATE
GAS VALVE
FIGURE 51
IMPORTANT
2
Low Fire CO
Max Vent
5.9−6.9
5.6−6.6
6.0−7.0
2
and CO.