Lennox LGM Series Manual page 33

STANDARD HEAT (130,000BTUH)
INSERTS (2)
TYPICAL GAS BURNER ASSEMBLY
BURNERS
BURNER
SUPPORT
ORIFICE
FIGURE 22
Orifice
Each burner uses an orifice (two types figure 23) which
is precisely matched to the burner input. Install only
the orifices with the same threads. The orifice is
threaded into the burner manifold. The burner is sup­
ported by the orifice and will easily slide off for service.
NOTE-Do not use thread sealing compound on the ori­
fices. Using thread sealing compound may plug the ori­
fices.
Each orifice and burner are sized specifically to the unit.
Refer to ProductZone@www.davenet.com for correct
sizing information.
INSERT LOCATION - DIRECT DRIVE ONLY
Note - No inserts on
medium heat.
BURNER
SUPPORT CAP
SENSOR
HIGH HEAT (180,000BTUH)
INSERTS (4)
FIGURE 21
5-Primary High Temperature Limits S10
S10 is the primary high temperature limit and is located on
the blower deck to the right of the blower housing.
Primary limit S10 is wired to the A3 ignition control which
energizes burner 1 control (A3). Its N.C. contacts open to
de-energize the ignition control when excessive tempera­
ture is reached in the blower compartment. The A55 unit
controller will energize the B4 blower when ever it senses
that the S10 limit has been opened. If the limit trips the blow­
er will be energized. Limit settings are factory set and can­
not be adjusted. If limit must be replaced, the same type
and set point must be used.
ORIFICE WITH
STRAIGHT THREADS
Tighten to 14 + .5 ft/lbs
Do not over-tighten.
Page 33
ORIFICE WITH
PIPE THREADS
Tighten to 6.25 + .5 ft.lbs.
Do not over-tighten.
FIGURE 23