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PRODUCT DESIGN
19
All propane gas equipment must conform to the safety
standards of the National Board of Fire Underwriters (See
NBFU Manual 58) or Natural Standards of Canada B149.2,
Installation Code for Propane Gas Burning Appliances and
Equipment.
For satisfactory operation, propane gas pressure must be 10
inch W.C. at the unit 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 container
or containers.
2. Proper pressure regulation. (Two-stage regulation is rec-
ommended from the standpoint of both cost and effi-
ciency.)
3. Pressure drop in lines between regulators, and between
second stage regulator and the appliance. Pipe size
required will depend on length of pipe run and total load of
all appliances.
Complete information regarding tank sizing for vaporization,
recommended regulator settings, and pipe sizing is available
from most regulator manufacturers and propane gas suppli-
ers.
Propane is an excellent solvent, and special pipe dope must
be used when assembling piping for this gas as it will quickly
dissolve white lead or most standard commercial com-
pounds. Shellac base compounds resistant to the actions of
liquefied petroleum gases such as Gasolac®, Stalactic®,
Clyde's or John Crane are satisfactory.
TYPICAL PROPANE PIPING
200 PSIG
Maximum
5 to 15 PSIG
(20 PSIG Max.)
Continuous
11" W.C.
Second Stage
Regulator
First Stage
Regulator
WARNING
PROPANE TANK SIZING (MINIMUM)
TANK SIZE REQUIRED IF LOWEST OUTDOOR
MAXIMUM GAS
TEMPERATURE (AVG. FOR 24 HOURS) REACHES
NEEDED TO
VAPORIZE*
32°F
20°F
10°F
0°F
-10°F
-20°F
-30°F
125K BTU/HR
(50 CFH)
115
GAL
115
GAL
115
GAL
250
GAL
250
GAL
400
GAL
600
GAL
250K BTU/HR
(100 CFH)
250
GAL
250
GAL
250
GAL
400
GAL
500
GAL
1000
GAL
1500
GAL
375K BTU/HR
(150 CFH)
300
GAL
400
GAL
500
GAL
500
GAL
1000
GAL
1500
GAL
2500
GAL
500K BTU/HR
(200 CFH)
400
GAL
500
GAL
750
GAL
1000
GAL
1500
GAL
2000
GAL
3500
GAL
750K BTU/HR
(300 CFH)
750
GAL
1000
GAL
1500
GAL
2000
GAL
2500
GAL
4000
GAL
5000
GAL
* AVERAGE RATE/HOUR WITHDRAWL IN 8 HOUR PERIOD
PROPANE GAS PIPING CHARTS
Sizing Between First and Second Stage Regulator
Maximum Propane Capacities listed are based on 1 PSIG Pressure Drop at 10
PSIG Setting. Capacities in 1,000 BTU/HR
3/8"
1/2"
5/8"
3/4"
7/8"
1/2"
3/4"
30
309
700
1,303
2,205
3,394
1,843
3,854
40
265
599
1,115
1,887
2,904
1,577
3,298
50
235
531
988
1,672
2,574
1,398
2,923
60
213
481
896
1,515
2,332
1,267
2,649
70
196
446
824
1,394
2,146
1,165
2,437
80
182
412
767
1,297
1,996
1,084
2,267
90
171
386
719
1,217
1,873
1,017
2,127
100
161
365
679
1,149
1,769
961
2,009
150
130
293
546
923
1,421
772
1,613
200
111
251
467
790
1,216
660
1,381
250
90
222
414
700
1,078
585
1,224
300
89
201
378
634
976
530
1,109
350
82
185
345
584
898
488
1,020
400
76
172
321
543
836
454
949
To convert to Capacities at 15 PSIG Settings -- Multiply by 1.130
To convert to Capacities at 5 PSIG Settings -- Multiply by 0.879
PIPE OR
TUBING
LENGTH,
FEET
NOMINAL PIPE SIZE,
SCHEDULE 40
TUBING SIZE, O.D., TYPE L