6
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
LENNOX HEARTH PRODUCTS • MERIT
®
SERIES B-VENT GAS FIREPLACES • 36" LMBV MODELS • CARE AND OPERATION INSTRUCTIONS
GENERAL INFORMATION
The fireplace models covered in this manual
are b-vented decorative fireplaces designed for
residential application.
The
Millivolt
appliances have a millivolt gas
control valve with piezo ignition system.
The
Electronic
appliances are designed to
operate on either natural or propane gas. An
electronic intermittent pilot system provides
safe, efficient operation. External electrical
power is required to operate these units.
These appliances comply with National Safety
Standards and are tested and listed by Warnock
Hersey (Report No. 3106807) to ANSI Z21.50,
latest edition (in Canada, CSA 2.22, latest edi-
tion), and CAN/CGA-2.17-M91 in both USA and
Canada, as vented gas fireplaces.
The Installation must conform to local codes
or, in the absence of local codes, with the
National Fuel Gas Code, ANSI Z223.1/NFPA
54-latest edition, or the Natural Gas and Propane
Installation Code, CAN/CGA B149.1-latest edi-
tion. The appliance, when installed, must be
electrically grounded in accordance with local
codes or, in the absence of local codes, the
latest edition of the National Electrical Code,
ANSI/NFPA 70, or the Canadian Electrical Code,
CSA C22.1 - latest editions.
bTU Input
Millivolt Models -
The millivolt appliances are
manually controlled and feature a spark igniter
(piezo) that allows the appliance's pilot gas to
be lit without the use of matches or batteries.
This system provides continued service in the
event of a power outage. The BTU Input for
these appliances is shown in
Table 1.
Electronic Models -
Electronic models have a
fixed rate gas valve. The BTU Input for these
appliances is shown in
Table 1.
Input (bTU) Gas valves (all models)
All Models Fuel Type
Input Rate (bTU / HR)
Millivolt
Natural
24,000
Millivolt
Propane
24,000
Electronic
Natural
24,000
Electronic
Propane
24,000
Table 1
Manifold Gas Supply Pressure
(all models)
Fuel #
Low
High
Natural
Gas
(Lo) 2.2" WC
(0.55 kPa)
(Hi) 3.5" WC
(0.87 kPa)
Propane (Lo) 6.3" WC
(1.57 kPa)
(Hi) 10.0" WC
(2.49 kPa)
Table 3
Inlet Gas Supply Pressure
(all models)
Fuel #
Minimum
Maximum
Natural Gas
4.5" WC
(1.12 kPa)
10.5" WC
(2.62 kPa)
Propane
11.0" WC
(2.74 kPa)
13.0" WC
(3.24 kPa)
Table 2
Gas Pressure - All Models
Tables 2 and 3
show the appliances' inlet and
manifold gas pressure requirements:
Test gauge connections are provided on the
front of the millivolt gas control valve (identified
E for the inlet and A for the manifold side
(see
Figure 2
)
. A 1/8" NPT test gage connection
is provided at the inlet and manifold side of
the electronic gas control valve
(
Figure 3
)
.
Propane tanks are at pressures that will cause
damage to valve components. Verify that the
tanks have step down regulators to reduce the
pressure to safe levels.
The appliance and its appliance main gas
valve must be disconnected from the gas
supply piping system during any pressure
testing of that system at test pressures in
excess of
1/2 psi (3.5 kPa).
The appliance must be isolated from the
gas supply piping system by closing its
equipment shutoff valve during any pressure
testing of the gas supply piping system at
test pressures
equal to or less than
1/2 psi
(3.5 kPa).
Orifice Sizes - Sea Level to High Altitude
(All Models)
These appliances are tested and approved for
installation at elevations of 0-4500 feet (0-1372
meters) above sea level using the standard burner
orifice sizes (marked with an "*" in
Table 4)
. For
elevations above 4500 feet, contact your gas
supplier or qualified service technician.
Deration -
At higher elevations, the amount
of BTU fuel value delivered must be reduced
by either:
• Using gas that has been derated by the gas
company.
• By changing the burner orifice to a smaller
size as regulated by the local authorities having
jurisdiction and by the (USA) National Fuel Gas
Code NFPA 54/ANSI Z223.1 - latest edition or,
in Canada, the CAN/CGA-B149.1 codes - latest
edition.
Install the appliance according to the regulations
of the local authorities having jurisdiction and,
in the USA, the National Fuel Gas Code NFPA
54 / ANSI Z223.1 - latest edition or, in Canada,
the CAN/CGA-B149.1 - latest edition.
Flame breadth, height and width will diminish
4% for every 1,000 feet of altitude.
burner Orifice Sizes (all models)
Elevation
Feet (meters)
Natural
Gas
drill size (inches)
Propane
Gas
drill size (inches)
0-4500
(0-1372)
#42 (0.0935")
*
H3721 •
(0.058")
*
67L28 •
Table 4
* Standard size installed at factory
• Part /Cat. Number
In Canada - CAN/CGA-2.17-M91 (R2009) (high
altitude): THE CONvERSION SHALL bE CAR-
RIED OUT bY A MANUFACTURER’S AUTHO-
RIZED REPRESENTATIvE, IN ACCORDANCE
WITH THE REQUIREMENTS OF THE MANU-
FACTURER, PROvINCIAL OR TERRITORIAL
AUTHORITIES HAvING JURISDICTION AND
IN ACCORDANCE WITH THE REQUIREMENTS
OF THE CAN/CGA-b149.1 OR CAN/CGA-b149.2
INSTALLATION CODES.
burn-in Period
During the first few fires of this appliance there
will be some odor due to the curing of the
paint and burning off of lubricants used in the
manufacturing process. Depending on your
use, the burn-in period may take a few hours
or a few days.
KEEP YOUR HOUSE WELL vENTILATED
DURING THE CURING PROCESS. THE ODOR
AND HAZE EMITTED DURING THE CURING
PROCESS CAN bE QUITE NOTICEAbLE AND
MAY SET OFF A SMOKE DETECTOR.
