Natural Gas - Lennox Hearth Products LMBV-42RMN Installation Instructions Manual

Step 5. Attach manometer to the manifold
side pressure test fitting and verify manifold
pressure reads 3.5 inches water column (0.87
kPa) for natural gas, and 10.0 inches water
column (2.49 kPa) for propane gas.
Step 6. Refer to Figure 25 and remove the
pilot hood assembly to access the hexed pilot
orifice. Remove and replace the orifice with
the one provided with the kit.
Electronic Appliances
Step 7. Honeywell Electronic Valves - See
Figure 27 and the instructions provided with
the kit. Remove the slotted cap screw, o-ring,
pressure-regulating adjusting screw and
spring. Retain all parts for possible later use.
Install new components from the kit. Black
cap and red spring for propane gas units.
Silver cap and stainless steel spring fro natural
gas units.
Before installing the cap, attach manometer to
the manifold side pressure test fitting and
adjust screw until pressure reads 3.5 inches
water column (0.87 kPa) for natural gas, and
10.0 inches water column (2.49 kPa) for pro-
pane gas.
Pilot
Orifice
Flare Nut
Note: If the ignitor assembly is damaged, a replacement kit is available, order Catalog Number 87L54.
Figure 26
Inlet Pressure Test Port
Manifold
Pressure
Test Port
Slotted
Cap
Adjusting
Screw
Figure 27
See Figure 26 and replace the pilot orifice as
follows: Remove the ignitor assembly retainer
clip, and carefully remove the ignitor assembly.
Exercise extreme care to prevent damage to
or breakage of the ignitor assembly. Remove
the screw securing the pilot assembly to its
mounting bracket. Back off the flare nut at the
end of the pilot gas line to free the pilot
assembly from the gas line. Remove the pilot
orifice and replace it with the one provided
with the conversion kit. Reinstall the pilot
assembly by reversing the steps detailed here.
Pilot
Assembly
Ignitor
Assembly
NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.
When reinstalling the ignitor assembly, use
extreme care to prevent damage and break-
age. Do not apply any leverage to the ignitor
assembly while restoring the retainer clip to
its original position.
All Models
Step 8. Unscrew the orifice from the manifold
and replace it with the one provided with the
kit, #37 (0.104) for natural gas units and
(0.065) for propane (see Figure 28 ) .
Spring
Figure 28
Step 9. Reassemble all removed components
by reversing the procedures outlined in the
preceding steps. Use pipe joint compound or
Teflon tape on all pipe fittings before installing
(ensure propane resistant compounds are used
in propane applications, do not use pipe joint
compounds on flare fittings). Check for leaks
(refer to Page 17, Step 6).
Step 10. Attach apropriate conversion kit
label (see Figure 29 ) next to the rating plate
on the appliance.
THIS APPLIANCE HAS BEEN CONVERTED TO:
THIS APPLIANCE HAS BEEN CONVERTED TO:
Retaining
Clip
Figure 29
Step 11. Turn on gas supply and test for gas
leaks.

NATURAL GAS

INPUT BTU/HR – 30,000
MANIFOLD PRESSURE – 3.5"
ORIFICE SIZE – #37 (0.104)
PROPANE/LPG
INPUT BTU/HR – 30,000
MANIFOLD PRESSURE – 10"
ORIFICE SIZE – (0.065)
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