Desa VMH3000TPA Electric Heater User Manual


 
109889
For more information, visit www.desatech.com
For more information, visit www.desatech.com
12
We recommend that you install a sediment trap in supply line as
shown in Figure 19, below. Locate sediment trap where it is within
reach for cleaning. Install in piping system between fuel supply and
heater. Locate sediment 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 con-
necting it to gas piping and/or fittings.
CONNECTING TO GAS SUPPLY
WARNING: A qualified service person must con-
nect heater to gas supply. Follow all local codes.
IMPORTANT:
Check gas line pressure before connecting heater to
gas line. Gas line pressure must be no greater than 14 inches of water.
If gas line pressure is higher, heater regulator damage could occur.
For propane/LP gas only, the installer must supply an external
regulator. 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 incoming 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.
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 equipment shutoff valve in an accessible
location. The equipment shutoff valve is for turning on or shutting
off the gas to the appliance.
Check your building codes for any special requirements for locating
equipment shutoff valve to heater.
Apply pipe joint sealant lightly to male NPT threads. This will
prevent excess sealant from going into pipe. Excess sealant in pipe
could result in clogged heater valves.
WARNING: Never connect natural gas heater to
private (non-utility) gas wells. This gas is commonly
known as wellhead gas.
CAUTION: Use only new, black iron or steel pipe.
Internally-tinned copper tubing may be used in cer-
tain 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 volume will occur.
CAUTION : Use pipe joint sealant that is resistant
to liquid petroleum (LP) gas.
INSTALLATION
Continued
WARNING: This appliance requires a 3/8" NPT
(National Pipe Thread) inlet connection to the pres-
sure regulator.
CAUTION: Never connect propane/LP heater di-
rectly to the propane/LP supply. This heater requires an
external regulator (not supplied). Install the external
regulator between the heater and propane/LP supply.
Propane/LP
Supply Tank
External
Regulator
Figure 18 - External Regulator with Vent Pointing Down
(Propane/LP Only)
Vent
Pointing
Down
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 21.
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap
Test
Gauge
Connection *
Tee Joint
Pipe Nipple
Cap
Sediment
Trap
Pressure
Regulator
3/8" NPT
Pipe Nipple
Ground
Union
Joint
Heater
Cabinet
3"
Minimum
Note:
Burner bracket
not shown for clarity
Equipment Shutoff
Valve *
Natural Gas
From Gas Meter
(5" W.C. to 10.5"
W.C. Pressure)
Propane/LP
From External
Regulator
(11" W.C. to 14"
W.C. Pressure)
INSTALLATION
Connecting To Gas Supply