Lennox LSS-35CN Installation Instructions Manual page 4

Gas Pressure - All Models
Tables 3 and 4 show the appliances' inlet and
manifold gas pressure requirements:
Inlet Gas Supply Pressure
(all models)
Fuel # Minimum
4.5" WC
Natural Gas
(1.12 kPa)
11.0" WC
Propane
(2.74 kPa)
Table 3
Manifold Gas Supply Pressure
(all models)
Fuel # Low
Natural (Lo) 2.2" WC
Gas (0.55 kPa)
(Lo) 6.3" WC
Propane
(1.57 kPa)
Table 4
Test gauge connections are provided on the
front of the gas control valve (identified IN
for the inlet and OUT for the manifold side).
The control valves have a 3/8" (10mm) NPT
thread inlet and outlet side of the valve (see
Figure 1).
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.
These appliances must be isolated from the
gas supply piping system (by closing their
individual manual shut-off valve) during any
pressure testing of the gas supply piping
system at test pressures equal to or less
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.
4
Maximum
Line (In) Test Port
10.5" WC
(2.61 kPa)
13.0" WC
Orange Wire
(3.23 kPa)
(From DFC Wire
Figure 1
High
(Hi) 3.5" WC
(0.87 kPa)
Gas Valve
(Hi) 10.0" WC
Refer to Figure 1 for key gas valve features.
(2.49 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 5).
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/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 diminish
4% for every 1,000 feet of altitude.
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Green Wire
(From DFC Wire
Harness)
Manifold (Out)
Test Port
Harness)
Connect GTMS
Wire Harness
Pressure
Regulator
Tower
Yellow Ground Wire
(From DFC Wire
Harness)
SIT Proflame Valve
Burner Orifice Sizes
Elevation 0-4500 feet ( 0-1372 meters)
Model Nat.Gas
Series drill size (inches)
#44 (0.086")*
LSS-35
Rear Burner 60J80•
#50 (0.070")*
LSS-35
Front Burner H4873•
#42 (0.094")*
LSS-40
Rear Burner H3721•
#45 (0.082")*
LSS-40
Front Burner 39L66•
* Standard size installed at factory
Table 5
• Part /Cat. Number
REQUIREMENTS FOR THE COMMON-
WEALTH OF MASSACHUSETTS
These fireplaces are approved for installation in
the US state of Massachusetts if the following
additional requirements are met:
• Install this appliance in accordance with
Massachusetts Rules and Regulations 248
C.M.R.
• Installation and repair must be done by a
plumber or gas fitter licensed in the Com-
monwealth of Massachusetts.
• The flexible gas line connector used shall
not exceed 36 inches (92 centimeters) in
length.
• The individual manual shut-off must be a
T-handle type valve.
Massachusetts Horizontal Vent Requirements
In the Commonwealth of Massachusetts, hori-
zontal terminations installed less than seven
(7) feet above the finished grade must comply
with the following additional requirements:
Propane
drill size (inches)
#55 (0.052")*
19L52•
#61 (0.039")*
35M91•
(0.054")*
88J59•
#56 (0.047")*
62L37•