Desa Tech CGN20TA installation manual Connecting to GAS Supply, Typical Inlet Pipe Diameters

CGN20TA

Blue Flame Vent-Free Natural Gas Heater

CONNECTING TO GAS SUPPLY

NOTICE: A qualified service per- son 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 well-head gas.

IMPORTANT: Check gas line pressure be- fore 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.

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 pres- sure will occur.

Typical Inlet Pipe Diameters

20,000 Btu/Hr 3/8" or greater

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 13).

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.

CAUTION: Use pipe joint seal- ant that is resistant to liquid pe- troleum (LP) gas.

Install sediment trap in supply line as shown in Figure 13. 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.

Pressure

Regulator

3/8" NPT Pipe Nipple

Ground Joint Union

Heater Cabinet

Test

Gauge

Connection*

Sediment

Trap

Tee Joint

Reducer Bushing to 1/8" NPT

1/8" NPT Plug Tap

Tee Joint

Pipe Nipple

Cap

Manual

Shutoff

Valve *

Typical Inlet Pipe from Gas Meter (4" W.C. to 10.5" W.C. Pressure)

3" Minimum

Figure 13 - 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 19.

10 104190