Vanguard Heating VMH3000TPS Gas Heater User Manual


 
12
106056-01
GAS RESIDENTIAL HEATERS
®
Installation must include a manual 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 21). An appliance main
gas valve (manual shutoff valve) must be
located within easy reach for turning the gas
supply on and off.
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap
Test Gauge
Connection *
Tee Joint
Pipe Nipple
Cap
Sediment Trap
Figure 21 - Gas Connection
* An A.G.A. design-certified manual shutoff valve with 1/8" NPT tap is an acceptable
alternative to test gauge connection. Purchase the optional A.G.A. design-certified manual
shutoff valve from your dealer. See Accessories, page 23.
Pressure
Regulator
3/8" NPT
Pipe Nipple
Ground
Union Joint
Heater
Cabinet
3" Minimum
Note:
Burner bracket
not shown for clarity
Manual Shutoff
Valve *
CONNECTING TO GAS
SUPPLY
Figure 20 - External Regulator with Vent
Pointing Down
CAUTION: Use pipe joint seal-
ant that is resistant to liquid pe-
troleum (LP) gas.
Propane/LP
Supply Tank
Vent
Pointing
Down
External
Regulator
From External
Regulator (11" W.C.
to 14" W.C. Pressure)
CAUTION: A qualified service
person must connect heater to
gas supply. Follow all local codes.
Never connect heater directly to
the propane/LP supply. This
heater requires an external regu-
lator (not supplied). Install the
external regulator between the
heater and propane/LP supply.
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
20. Pointing the vent down protects it from
freezing rain or sleet.
WARNING: A qualified service
person must connect heater to gas
supply. Follow all local codes.
INSTALLATION
Continued
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 diameter to allow
proper gas volume to heater. If
pipe is too small, undue loss of
pressure will occur.
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.
Install sediment trap in supply line as shown
in Figure 21. Locate sediment trap where it
is within reach for cleaning. 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 pip-
ing and/or fittings.