9
Length of
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
Pressure = .50 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)
Nominal Black Pipe Size (inches)
BTUH Furnace Input
Heating Value of Gas (BTU/Cubic Foot)
CFH =
Proper Piping Practice
Gas Piping Checks
There will be air in the gas supply line after testing for leaks
on a new installation. Therefore, the air must be bled from
the line by loosening the ground joint union until pure gas
is expelled. Tighten union and wait for five minutes until all
gas has been dissipated in the air. Be certain there is no
open flame in the vicinity during air bleeding procedure.
The unit is placed in operation by closing the main electri-
cal disconnect switch for the unit.
PROPANE GAS INSTALLATIONS
WARNING
To avoid property damage, personal injury or death due to
fire or explosion caused by a propane gas leak, install a gas
detecting warning device. If the propane gas unit is installed
in an excavated area or a confined space, a confined space, a
warning device is required due to:
•
Propane gas is heavier than air and any leaking gas can
settle in any low areas or confined spaces.
•
Propane gas odorant may fade, making the gas
undetectable except with a warning device.
IMPORTANT NOTE: For Natural gas to LP gas
conversion, Conversion Kit “LPM-08” must be used.
Consult your dealer for appropriate conversion
kit(s).
All propane gas equipment must conform to the safety
standards of the National Board of Fire Underwriters (See
NBFU Manual 58).
For satisfactory operation, propane gas supply pressure
must be within 9.7 - 10.3 inches W.C. at the manifold with
all gas appliances in operation. Maintaining proper gas
pressure depends on three main factors:
1.
Vaporization rate, which depends on (a) temperature
of the liquid, and (b) wetted surface area of the con
-
tainer or containers.
2. Proper pressure regulation.
3. Pressure drop in lines between regulators, and be-
tween second stage regulator and the appliance. Pipe
size required will depend on length of pipe run and
total load of all appliances.
Tanks and Piping
Complete information regarding tank sizing for vaporiza-
tion, recommended regulator settings and pipe sizing is
available from most regulator manufacturers and propane
gas suppliers.
Since propane gas will quickly dissolve white lead or most
standard commercial compounds, special pipe dope must
be used. Shellac base compounds resistant to the actions
of liquefied petroleum gases such as Gasolac®, Stalactic®,
Clyde’s® or John Crane® are satisfactory.
See Typical Propane Gas Piping figure for typical piping
arrangement.
CAUTION
To prevent property damage or personal injury due to fire,
the following instructions must be performed regarding gas
connections and pressure testing
•
The unit and its gas connections must be leak tested be-
fore placing in operation. Because of the danger of explo-
sion or fire, never use a match or open flame to test for
leaks. Never exceed specified pressure for testing. Higher
pressure may damage gas valve and cause overfiring which
may result in premature heat exchanger failure.
•
This unit and its shut-off valve must be disconnected
from the gas supply during any pressure testing of that
system at pressures in excess of 1/2 PSIG (3.48 kPA).
•
This unit must be isolated from the gas supply system by
closing its 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 (3.48 kPA).
WARNING
To avoid property damage or personal injury, be sure there
is NO OPEN FLAME in the vicinity during air bleeding.
