Desa NZ107 NZ116, NZ119 Installation, Connecting To Gas Supply, Pointing Down, Gas Connection

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 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" of water. If gas line pressure is higher, heater regulator damage could occur.

CAUTION: For propane/LP gas, never connect heater di- rectly to the propane/LP supply. This heater requires an external regulator (not supplied). Install theexternalregulatorbetweenthe heater and propane/LP supply.

For propane/LP gas, 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" of water. If you do not reduce incom-

Propane/LP
Supply Tank	External
	Regulator
	with Vent
	Pointing
	Down

Figure 16 - External Regulator With Vent

Pointing Down

ing gas pressure, heater regulator damage could occur. Install the external regulator with the vent pointing down as shown in Figure

16.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

16-18,000 Btu/hr models - 3/8" or greater

26-30,000 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 17).

Pressure
Regulator				3/8" NPT
Regulator				Pipe
Bracket				Nipple
Heater				Ground
Cabinet				Joint
Connection*				Union
	Tee Joint			Equipment
	Reducer			Shutoff
	Bushing to			Valve*
Gauge	1/8" NPT			Natural Gas
	Plug Tap		Min.
				Meter (7" W.C.
Test	1/8" NPT		3"	From Gas
				to 10.5" W.C.
	Tee	Pipe Cap		Pressure)
				Propane/LP
	Joint	Nipple
	Sediment Trap			From External
				Regulator

(11" W.C. to 14" W.C. Pressure)

Figure 17 - Gas Connection

*A CSA design-certified equipment shutoff valve with 1/8" NPT tap is an acceptable al- ternative to test gauge connection. Purchase the optional CSA design-certified equipment shutoff valve from your dealer. See Acces-

sories, page 30.

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