SYSTEM OPERATION
19
A different pressure switch may be required at high altitude
regardless of the BTU/ft
3
content of the fuel used. Refer to the
product Specification Sheet or Technical Manual for a tabular
listing of appropriate altitude ranges and corresponding
manufacturer’s pressure switch kits.
PROPANE GAS CONVERSION
WARNING
P
O
SS
IBLE
P
R
OPE
R
TY
DAMAGE,
PE
RS
ONAL
IN
J
U
R
Y
O
R
DEATH
MAY
OCCU
R
IF
THE
CO
RR
ECT
CONVE
RS
ION
K
IT
S
A
R
E
NOT
IN
S
TALLED.
T
HE
APP
R
OP
R
IATE
K
IT
S
MU
S
T
BE
APPLIED
TO
IN
S
U
R
E
S
AFE
AND
P
R
OPE
R
FU
R
NACE
OPE
R
ATION.
A
LL
CONVE
RS
ION
S
MU
S
T
BE
PE
R
FO
R
MED
BY
A
Q
UALIFIED
IN
S
TALLE
R
O
R S
E
R
VICE
AGENCY.
This unit is configured for natural gas. The appropriate
manufacturer’s propane gas conversion kit, must be applied
for propane gas installations.
• • Single-stage 80% furnace modelsusing a Honeywell
VR8215 single stage valve or a White-Rodgers 36J22
use LPT-03 LP Conversion Kit.
Refer to the specification sheet for the model you are
servicing.
Refer to the “propane gas and/or High Altitude
Installations” section for details.
GAS VALVE
This unit is equipped with a 24 volt gas valve controlled
during furnace operation by the integrated control module.
As shipped, the valve is configured for natural gas. The valve
is field convertible for use with propane gas by using the
appropriate propane gas conversion kit. Taps for measuring
the gas supply pressure and manifold pressure are provided
on the valve.
NOTE: The gas supply pressure on White-Rodger “J”
model gas valve, used on single stage furnaces, can be
checked with a gas pressure test kit (Part #0151K00000S)
available through our authorized distributors.
The gas valve has a manual ON/OFF control located on
the valve itself. This control may be set only to the “ON” or
“OFF” position. Refer to the
Lighting Instructions Label
or the
“Putting the Furnace Into Operation”
section of this manual or
the installation instructions for use of this control during start
up and shut down periods.
GAS PIPING CONNECTIONS
CAUTION
T
O
AVOID
PO
SS
IBLE
UN
S
ATI
S
FACTO
R
Y
OPE
R
ATION
O
R
E
Q
UIPMENT
DAMAGE
DUE
TO
UNDE
R
FI
R
ING
OF
E
Q
UIPMENT,
U
S
E
THE
P
R
OPE
R S
IZE
OF
NATU
R
AL/P
R
OPANE
GA
S
PIPING
NEEDED
WHEN
R
UNNING
PIPE
F
R
OM
THE
METE
R
/TAN
K
TO
THE
FU
R
NACE.
The gas piping supplying the furnace must be properly sized
based on the gas flow required, specific gravity of the gas,
and length of the run. The gas line installation must comply
with local codes, or in their absence, with the latest edition of
the National Fuel Gas Code, NFPA 54/ANSI Z223.1.
Length of
Nominal Black Pipe Size
Pipe in Feet
1/2"
3/4"
1"
1 1/4"
1 1/2"
10
132
278
520
1050
1600
20
92
190
350
730
1100
30
73
152
285
590
980
40
63
130
245
500
760
50
56
115
215
440
670
60
50
105
195
400
610
70
46
96
180
370
560
80
43
90
170
350
530
90
40
84
160
320
490
100
38
79
150
305
460
CFH =
(Pressure 0.5 psig or less and pressure drop of 0.3" W.C.; Based on 0.60 Specific
Gravity Gas)
Natural Gas Capacity of Pipe
In Cubic Feet of Gas Per Hour (CFH)
BTUH Furnace Input
Heating Value of Gas (BTU/Cubic Foot)
To connect the furnace to the building’s gas piping, the installer
must supply a ground joint union, drip leg, manual shutoff
valve, and line and fittings to connect to gas valve. In some
cases, the installer may also need to supply a transition piece
from 1/2” pipe to a larger pipe size.
The following stipulations apply when connecting gas piping.
Refer to the following figures for typical gas line connections
to the furnace.
1. Use black iron or steel pipe and fittings for the building
piping.
2. Use pipe joint compound on male threads only. Pipe
joint compound must be resistant to the action of the
fuel used.
3. Use ground joint unions.
4. Install a drip leg to trap dirt and moisture before it can
enter the gas valve. The drip leg must be a minimum of
three inches long.
5. Install a 1/8” NPT pipe plug fitting, accessible for test
gage connection, immediately upstream of the gas
supply connection to the furnace.
6. Use two pipe wrenches when making connection to
the gas valve to keep it from turning. The orientation of
the gas valve on the manifold must be maintained as
shipped from the factory.
7. Install a manual shutoff valve between the gas meter
and unit within six feet of the unit. If a union is installed,
the union must be downstream of the manual shutoff
valve, between the shutoff valve and the furnace.
8. Tighten all joints securely.
9. Connect the furnace to the building piping by one of the
following methods:
•
– Rigid metallic pipe and fittings.
•
– Semi-rigid metallic tubing and metallic fittings.
Aluminum alloy tubing must not be used in exterior
locations. In order to seal the grommet cabinet
penetration, rigid pipe must be used to reach the outside
of the cabinet. A semi-rigid connector to the gas piping
may be used from there.
