Btu Input; Gas Pressure Requirements; Orifice Sizes; Burn-In Period - Lennox Hearth Products MPDT-3328CNM-B Care And Operation Instructions Manual

LENNOX HEARTH PRODUCTS • MERIT
GENERAL INFORMATION
(continued)

BTU Input

These fireplaces are designed as supplemental
heaters. Therefore, it is advisable to have an
alternate primary heat source when installed
in a dwelling.
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.
Millivolt models come standard with a manually-
modulated gas valve; flame appearance and heat
output can be controlled at the gas valve. The BTU
Input for these appliances is shown in Table 1.
Electronic Models - Electronic models have a
fixed rate gas valve. Input of electronic models
is shown in Table 1.
Input (BTU/HR) Gas Valves (all models)
Input Rate (BTU / HR)
Models
Nat. Gas
MPDT/R-3328 17,500 high
(Millivolt) 11,700 low
MPD-3530 20,000 high
(Millivolt) 12,800 low
MPD-4035 27,000 high
(Millivolt) 18,500 low
MPD-4540 29,000 high
(Millivolt) 20,500 low
MPDT/R-3328
17,500
(Electronic)
MPD3530
20,000
(Electronic)
MPD4035
27,000
(Electronic)
MPD4540
29,000
(Electronic)
Table 1
PLUS DIRECT VENT GAS FIREPLACES (MPD33/35/40/45) • CARE AND OPERATION INSTRUCTIONS
®
Gas Pressure - All Models
Tables 2 and 3 show the appliances' inlet and
manifold gas pressure requirements:
Inlet Gas Supply Pressure
Fuel #
Natural Gas
Propane
Table 2
Manifold Gas Supply Pressure
Fuel #
Natural
Gas
Propane
Table 3
Prop. Gas
Test gauge connections are provided on the
17,500 high
front of the millivolt and electronic gas control
14,000 low
valve (identified IN for the inlet and OUT for the
manifold side). The control valves have a 3/8"
20,000 high
15,200 low
(10mm) NPT thread inlet and outlet side of the
valve (refer to Figures 1 and 2).
27,000 high
21,500 low
Propane tanks are at pressures that will cause
29,000 high
damage to valve components. Verify that the
22,500 low
tanks have step down regulators to reduce the
17,500 pressure to safe levels.
These appliances must be isolated from the
20,000
gas supply piping system (by closing their
individual manual shut-off valve) during any
27,000
pressure testing of the gas supply piping
system at test pressures equal to or less
29,000
than 1/2 psig (3.5 kPa).
These appliances and their individual shut-off
valves must be disconnected from the gas
supply piping system during any pressure
testing of that system at pressures greater
than 1/2 psig (3.5 kPa).
These appliances must not be connected to a
chimney or flue serving a separate solid fuel
burning appliance.
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.
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
(all models)
Minimum Maximum
4.5" WC 10.5" WC
(1.12 kPa) (2.61 kPa)
11.0" WC 13.0" WC
(2.74 kPa) (3.23 kPa)
(all models)
Low High
(Lo) 1.6" WC (Hi) 3.5" WC
(0.40 kPa) (0.87 kPa)
(Lo) 6.3" WC (Hi) 10.0" WC
(1.57 kPa) (2.49 kPa)
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 or 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/
CSA-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/CSA-B149.1 - latest edition.
Flame breadth, height and width will dimenish
4% for every 1,000 feet of altitude.
Burner Orifice Sizes
Elevation 0-4500 feet ( 0-1372 meters)
Model Nat.Gas
Series drill size (inches)
#45 (0.0820")*
MPDT-3328
39L66•
MPDR-3328
#44 (0.0860")*
MPD-3530
60J80•
#37 (0.1040")*
MPD-4035
24M10•
#36 (0.1065")*
MPD-4540
18L40•
* Standard size installed at factory
Table 4
• Part /Cat. Number

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.
If an optional blower is installed, do not turn it
on during the burn-in period.
NOTICE:
A white film may develop
on the glass enclosure panel during
the first few fires as part of the burn-in
process.
The first few times you use the
fireplace, clean the glass after each use
(AFTER THE GLASS HAS COMPLETELY
COOLED); otherwise, the white film
will bake onto the glass and become
difficult to remove.
See glass cleaning instructions on
Page 9.
Propane
drill size (inches)
0.048 inch
99K78•
#55 (0.0520")*
19L52•
0.063 inch
21L01•
#52 (0.0635")*
37G00•
7