Desa GWP30T, GWP20T, GWN20T, WMN20, GN30T, GP30T, GWN30T Connecting To Gas Supply

INSTALLATION

Continued

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 commonlyknownaswellheadgas.

IMPORTANT: For natural gas, 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 regula- tor damage could occur.

CAUTION: For propane/LP gas,neverconnectheaterdirectly 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.

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

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

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.

WARNING: Use pipe joint sealant that is resistant to liquid petroleum (LP) gas.

Install sediment trap in supply line as shown in Figure 15, page 13. Locate sediment trap where it is within reach for cleaning. Locate sediment trap where trapped matter is not likely to freeze. A sedi- ment trap traps moisture and contaminants. This keeps them from going into heater controls. If sedi- ment trap is not installed or is installed wrong, heater may not run properly.

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.

Propane/LP Supply Tank

External Regulator

Vent

Pointing

Down

Figure 14 - External Regulator With Vent

Pointing Down

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