Lennox Hearth INTERTEK LMBV-42REN - Manual (Page 19)

19
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
LENNOX HEARTH PRODUCTS • MERIT ® SERIES B-VENT GAS FIREPLACES • 42" LMBV MODELS • INSTALLATION INSTRUCTIONS
THIS APPLIANCE HAS BEEN CONVERTED TO:
NATURAL GAS
INPUT BTU/HR – 30,000
MANIFOLD PRESSURE – 3.5"
ORIFICE SIZE – #37 (0.104)
THIS APPLIANCE HAS BEEN CONVERTED TO:
PROPANE/LPG
INPUT BTU/HR – 30,000
MANIFOLD PRESSURE – 10"
ORIFICE SIZE – (0.065)
Step 5. All Millivolt Systems – Attach ma-
nometer to the manifold side pressure test
fitting and verify manifold pressure reads
3.5" water column (0.87 kPa) for natural
gas, and 10.0" water column (2.49 kPa)
for propane gas.
Step 6. Refer to Figure 30 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 32 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" water
column (0.87 kPa) for natural gas, and 10.0"
water column (2.49 kPa) for propane gas.
Figure 31
pilot
Orifice
pilot
Assembly
Igniter
Assembly
Retaining
Clip Flare Nut
NOTE: If the igniter is damaged, a replacement
kit is available, order Catalog No. 87L54.
Figure 32
Figure 33
When reinstalling the igniter assembly,
use extreme care to prevent damage and
breakage. Do not apply any leverage to
the igniter 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 33).
See Figure 31 and replace the pilot orifice as
follows: Remove the Igniter assembly retainer
clip, and carefully remove the igniter assembly.
exercise extreme care to prevent damage to
or breakage of the igniter 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.
Spring
Adjusting
Screw
Slotted
Cap
P S I
OF
F
I
ON CONTROL
IG N IT E
Manifold
Pressure
Test Port
Inlet Pressure Test Port
burner Orifice Sizes (all models)
elevation
Feet (meters)
Natural
Gas
drill size (inches)
propane
Gas
drill size (inches)
0-4500
(0-1372)
#37 (0.104") *
H5830 •
1.65mm (0.065") *
H5831 •
Table 5
* Standard size installed at factory
• Part /Cat. Number
Step 11. Turn on gas supply and test for gas
leaks.
Step 12. Attach manometer to the manifold
side pressure test fitting and verify manifold
pressure reads 3.5" water column (0.87 kPa)
for natural gas, and 10.0" water column (2.49
kPa) for propane gas.
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 11, Step 6).
Step 10. Attach appropriate conversion kit
label (see Figure 34) next to the rating plate
on the appliance.
Figure 34