Service Manual

PRODUCT DESIGN
18
TANKS AND PIPING - PROPANE UNITS
WARNING
PERSONAL INJURY HAZARD
IRON OXIDE (RUST) CAN REDUCE THE LEVEL OF
ODORANT IN PROPANE GAS. A GAS DETECTING
DEVICE IS THE ONLY RELIABLE METHOD TO DETECT
A PROPANE GAS LEAK. CONTACT YOUR LOCAL
PROPANE SUPPLIER ABOUT INSTALLING A GAS
DETECTING WARNING DEVICE TO ALERT YOU IN
THE EVENT THAT A GAS LEAK SHOULD DEVELOP.
FAILURE TO DETECT A PROPANE GAS LEAK COULD
RESULT IN AN EXPLOSION OR FIRE WHICH COULD
CAUSE SERIOUS PERSONAL INJURY OR DEATH.
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
recommended from the standpoint of both cost and
efficiency.)
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