Goodman [A/G]PG, Service Instructions Manual

PRODUCT DESIGN

16

DRIP LEG

MANUAL
SHUT-OFF
VALVE

GROUND JOINT UNION
(INSTALLED AHEAD OF GAS VALVE)

GROMMET

NOTE:  

The unit gas supply entrance is factory sealed with

plugs.  Keep plugs in place until gas supply is ready to be
installed.  Once ready, replace the plugs with the supplied
grommets and install gas supply line.

CHECKING THE GAS PIPING

To avoid the possibility of property damage, personal
injury or fire, the following instructions must be
performed regarding gas connections and pressure
testing.

The unit and its gas connections must be leak tested before
placing in operation.  Because of the danger of explosion or
fire, never use a match or open flame to test for leaks.  Never
exceed specified pressure for testing.  Higher pressure may
damage the gas valve and cause overfiring which may result in
heat exchanger failure.

This unit must be isolated from the gas supply system by
closing its individual manual shutoff 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).

TANKS AND PIPING - PROPANE UNITS

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 stan-
dards of the National Board of Fire Underwriters (See NBFU
Manual 58) or Natural Standards of Canada B149.2, Installa-
tion 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 opera-
tion.  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 efficiency.)

3. Pressure drop in lines between regulators, and between

second stage regulator and the appliance.  Pipe size re-
quired 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 suppliers.

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 compounds.
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