Goodman GMVM Service Instructions Manual page 43

OPERATION
• Tighten all joints securely.
• Connect the furnace to the building piping by one of the
following methods:
–
Rigid metallic pipe and fittings.
–
Semi-rigid metallic tubing and metallic fittings.
Aluminum alloy tubing must not be used in exterior lo-
cations. In order to seal the grommet cabinet penetra-
tion, rigid pipe must be used to reach the outside of the
cabinet. A semi-rigid connector to the gas piping may
be used from there.
• Use listed gas appliance connectors in accordance with
their instructions. Connectors must be fully in the same
room as the furnace.
• Protect connectors and semirigid tubing against physi-
cal and thermal damage when installed. Ensure alumi-
num-alloy tubing and connectors are coated to protect
against external corrosion when in contact with ma-
sonry, plaster, or insulation, or subjected to repeated
wetting by liquids such as water (except rain water),
detergents, or sewage.
D /S I P
IRECT TANDARD NLET IPING
E
DGES OF SHEET METAL HOLES MAY BE SHARP
PRECAUTION WHEN REMOVING HOLE PLUGS
When gas piping enters directly to the gas valve through the stan-
dard inlet hole, the installer must supply straight pipe with a ground
joint union to reach the exterior of the furnace. The rigid pipe must
be long enough to reach the outside of the cabinet to seal the
grommet cabinet penetration. A semi-rigid connector to the gas
piping can be used outside the cabinet per local codes.
I /A I P
NDIRECT LTERNATE NLET
When gas piping enters indirectly to the gas valve through the
alternate gas inlet hole the following fittings (starting from the gas
valve) to reach the outside of the cabinet must be supplied:
•
Close nipple.
•
90 degree elbow.
•
2½ inch nipple.
•
90 degree elbow.
•
Straight pipe, with a ground joint union, to reach the exterior
of the furnace. The rigid pipe must be long enough to reach
the outside of the cabinet so as to seal the grommet cabinet
penetration. A semi-rigid connector to the gas piping can be
used outside the cabinet per local codes.
WARNING
. U
SE GLOVES AS A
.
IPING
G P C
AS IPING HECKS
Before placing unit in operation, leak test the unit and gas con-
nections.
T
O AVOID THE POSSIBILITY OF EXPLOSION OR FIRE
OR OPEN FLAME TO TEST FOR LEAKS
Check for leaks using an approved chloride-free soap and water
solution, an electronic combustible gas detector, or other ap-
proved testing methods.
NOTE: Never exceed specified pressures for testing. Higher
pressure may damage the gas valve and cause subsequent
overfiring, resulting in heat exchanger failure.
Disconnect this unit and shutoff valve from the gas supply piping
system before pressure testing the supply piping system with
pressures in excess of 1/2 psig (3.48 kPa).
Isolate this unit from the gas supply piping system by closing its
external manual gas shutoff valve before pressure testing supply
piping system with test pressures equal to or less than 1/2 psig
(3.48 kPA).
P G T
ROPANE AS ANKS AND
I
F THE GAS FURNACE IS INSTALLED IN A BASEMENT
,
AREA OR CONFINED SPACE IT IS STRONGLY RECOMMENDED TO
CONTACT A PROPANE SUPPLIER TO INSTALL A GAS DETECTING WARNING
DEVICE IN CASE OF A GAS LEAK
S
•
INCE PROPANE GAS IS HEAVIER THAN AIR
SETTLE IN ANY LOW AREAS OR CONFINED SPACES
P
•
ROPANE GAS ODORANT MAY FADE
EXCEPT WITH A WARNING DEVICE
A gas detecting warning system is the only reliable way to detect
a propane gas leak. Rust can reduce the level of odorant in pro-
pane gas. Do not rely on your sense of smell. Contact a local
propane gas supplier about installing a gas detecting warning
system. If the presence of gas is suspected, follow the instruc-
tions listed in the Safety Precautions section of this manual.
All propane gas equipment must conform to the safety standards
of the National Board of Fire Underwriters, NBFU Manual 58.
For satisfactory operation, propane gas pressure must be 10"
WC + .5" WC at the furnace manifold with all gas appliances in
operation. Maintaining proper gas pressure depends on three main
factors:
1. Vaporization rate, depending on temperature of the liq-
uid, and "wetted surface" area of the container or con-
tainers.
WARNING
,
NEVER USE A MATCH
.
P
IPING
WARNING
,
AN EXCAVATED
.
,
ANY LEAKING GAS CAN
.
,
MAKING THE GAS UNDETECTABLE
.
43