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901918-01J
10
INSTALLATION
Continued
Figure 9 - Technical Information Charts
BURNER ORIFICE
Log
Size
Natural
Propane/LP
In.
Num.
In.
Num.
18"
0.10
1
0.07
49
FUEL INLET PRESSURE
SPECIFICATIONS (W.C.)
Min.
Max.
NG
5.5" (140 mm)
10.5" (67 mm)
LP
11" (80 mm)
1" (0 mm)
Description
Btu Input
Natural Gas
Btu Input
Propane Gas
18" Dual
Burner
55,000
45,000
SIzING PROPANE/LP SUPPLY TANK
CAUTION: For propane/LP
gas, make sure external regula
-
tor has been installed between
propane/LP supply and heater.
See guidelines under
Connect-
ing Propane/LP Supply Tank
.
The models CHAM45P, FC45AP and VC45AP
are supplied with a two stage, propane/LP regu
-
lator and 10 foot (3 m) hose assembly ready for
connection to 3/8" flare fitting at inlet of manual
control valve.
The propane/LP regulator is factory set at 11"
(280 mm) w.c. and can be connected to a properly
sized and approved propane/LP supply tank. This
supply tank can be purchased from your propane/
LP or builder supplier.
The propane/LP cylinder used must be constructed
and marked as (DOT or CAN/CSA B339) ap
-
proved for vapor withdrawal and equipped with a
safety relief type ON/OFF valve with a protective
collar. The propane/LP cylinder must be sized
according to the input rate and expected ambient
temperature of fuel in container.
The first table (Figure 10) indicates the vaporiza
-
tion rate of propane/LP fuel at various Btu/Hr input
rates for a range of cylinder sizes and ambient fuel
temperatures. An undersized or under filled pro
-
Cylinder Size
BTU Content
14.1 oz (0.4 kg)
19,000
16.4 oz (0.5 kg)
,100
5 lb (. kg)
107,800
10 lb (4.5 kg)
15,600
0 lb (9.1 kg)
41,00
100 lb (45 kg)
,156,000
50 gal (946 L)
,875,000
500 gal (1900 L)
45,750,000
1000 gal (790 L)
91,500,000
Pounds of
propane/LP
in cylinder
Max. Continuous Draw in
BTU per hour at various
temperatures
0° F
(-17.8° C)
0° F
(-6.7° C)
40° F
(4.4° C)
100
11,000 167,000 14,000
90
104,000 15,000 00,000
80
94,000
17,000 180,000
70
8,000
1,000 160,000
60
75,000
109,000 140,000
50
64,000
94,000 15,000
40
55,000
79,000 105,000
0
45,000
66,000
85,000
0
6,000
51,000
68,000
10
8,000
8,000
49,000
Figure 10 - Vaporization Rate (per 100
pound cylinder)
Figure 11 - Maximum Btu Content
pane/LP tank, when evacuating at lower outdoor
temperatures, can cause a condition known as “va
-
por lock” to occur. Vapor lock prevents vaporized
fuel from reaching the burner system.
It is important to use a cylinder size based on an
input rate higher than 45,000 Btu/Hr at the lowest
expected outdoor ambient temperature to insure
vaporization of fuel.
The second table (Figure 11) indicates the maxi
-
mum Btu content of a full cylinder and can be used
to calculate the approximate operating hours.
Example:
20 pounds propane/LP = 431,200 Btu’s
431,200 Btu ÷ 45,000 Btu/Hr = 9.5 Hours
Actual operating hours may vary depending on
outdoor temperature and fill quality of tank.
