www.desatech.com 113680-01A
12
CONNECTING TO GAS SUPPLY
WARNING: This appliance
requires a 3/8" NPT (National
Pipe Thread) inlet connection to
the pressure regulator.
WARNING: A qualified ser-
vice person must connect heater
to gas supply. Follow all local
codes.
WARNING: For natural gas,
never connect heater to private
(non-utility) gas wells. This gas is
commonly known as wellhead gas.
IMPORTANT:
For natural gas, check gas line
pressure before connecting heater to gas line. Gas
line pressure must be no greater than 10.5 inches
of water. If gas line pressure is higher, heater regu-
lator damage could occur.
CAUTION: For propane/LP
gas, never connect heater directly
to the propane/LP supply. This
heater requires an external regu-
lator (not supplied). Install the ex-
ternal regulator between the
heater and propane/LP supply.
INSTALLATION
Continued
Figure 14 - External Regulator With Vent
Pointing Down
External Regulator
Propane/LP
Supply Tank
Vent
Pointing
Down
For propane/LP gas, the installer must supply an
external regulator. The external regulator will re-
duce incoming gas pressure. You must reduce in-
coming gas pressure to between 11 and 14 inches
of water. If you do not reduce incoming gas pres-
sure, heater regulator damage could occur. Install
the external regulator with the vent pointing down
as shown in Figure 14. Pointing the vent down
protects it from freezing rain or sleet.
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
large enough diameter to allow
proper gas volume to heater. If
pipe is too small, undue loss of
volume will occur.
Typical Inlet Pipe Diameters
10,000/20,000 Btu/Hr Models - 3/8" or greater
30,000 Btu/Hr Models - 1/2" or greater
Installation must include 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 15, page 13).
IMPORTANT:
Install an equipment shutoff valve
in an accessible location. The equipment shutoff
valve is for turning on or shutting off the gas to
the appliance.
Apply pipe joint sealant lightly to male NPT
threads. This will prevent excess sealant from go-
ing into pipe. Excess sealant in pipe could result
in clogged heater valves.
3. For carpeted floors, make a small cut with a
sharp knife at marked locations prior to drill-
ing. If mounting base to a wood floor, drill 1/8
inch diameter hole, 3/4 inch deep. (Do not use
anchors in wood floors).
If mounting base to a concrete floor, drill with
1/4 inch diameter concrete drill bit, 1
3
/8 inches
into floor. Insert anchors completely into holes.
4. Reposition heater with base feet over holes.
Secure base to floor with wood screws. See
Figure 13, page 11.