Connecting To Gas Supply - Vanguard VMH3000TPA Owner's Operation And Installation Manual

PROPANE/LP GAS RESIDENTIAL HEATERS
INSTALLATION
Continued
CONNECTING TO GAS
SUPPLY
WARNING: This appliance re-
quires a 3/8" NPT (National Pipe
Thread) inlet connection to the
pressure regulator.
WARNING: A qualified service
person must connect heater to gas
supply. Follow all local codes.
WARNING: Never connect
heater to private (non-utility) gas
wells. This gas is commonly
known as wellhead gas.
The installer must supply an external regu-
lator. The external regulator will reduce
incoming gas pressure. You must reduce
incoming gas pressure to between 11 and 14
inches of water. If you do not reduce incom-
ing gas pressure, heater regulator damage
could occur. Install external regulator with
the vent pointing down as shown in Figure
18. Pointing the vent down protects it from
freezing rain or sleet.
Propane/LP
Supply Tank
Figure 18 - External Regulator with Vent
Pointing Down
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®
CAUTION: Use only new,
black iron or steel pipe. Inter-
nally-tinned copper tubing may
be used in certain areas. Check
your local codes. Use pipe of 1/2"
or greater
proper gas volume to heater. If
pipe is too small, undue loss of
pressure will occur.
Installation must include an equipment
shutoff valve, union, and plugged 1/8" NPT
tap. Locate NPT tap within reach for test
gauge hook up. NPT tap must be upstream
from heater (see Figure 19).
IMPORTANT: Install an equipment shutoff
valve in an accessible location. The equip-
ment shutoff valve is for turning on or
shutting off the gas to the appliance.
Apply pipe joint sealant lightly to male
threads. This will prevent excess sealant
from going into pipe. Excess sealant in pipe
could result in clogged heater valves.
External
Regulator
Test Gauge
Connection *
Vent
Pointing
Down
Sediment Trap
Figure 19 - Gas Connection
* A CSA design-certified equipment shutoff valve with 1/8" NPT tap is an acceptable
alternative to test gauge connection. Purchase the optional CSA design-certified equipment
shutoff valve from your dealer. See Accessories, page 23.
diameter to allow
Pressure
Regulator
3/8" NPT
Pipe Nipple
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap
Tee Joint
Pipe Nipple
Cap
12
CAUTION: Use pipe joint seal-
ant that is resistant to liquid pe-
troleum (LP) gas.
We recommend that you install a sediment
trap in supply line as shown in Figure 19.
Locate sediment trap where it is within
reach for cleaning. Install in piping system
between fuel supply and heater. Locate sedi-
ment trap where trapped matter is not likely
to freeze. A sediment trap traps moisture
and contaminants. This keeps them from
going into heater controls. If sediment trap
is not installed or is installed wrong, heater
may not run properly.
IMPORTANT: Hold pressure regulator with
wrench when connecting it to gas piping
and/or fittings.
Note: Burner bracket
not shown for clarity
Ground
Union Joint
Equipment
Shutoff Valve *
From External
Regulator (11" W.C.
to 14" W.C. Pressure)
3" Minimum
Heater
Cabinet
107098