Desa VN10A Checking Gas Connections, Pressure Testing Gas Supply Piping System, Installation

Models: VN10A

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Pressure Testing Gas Supply Piping System

INSTALLATION

Connecting To Gas Supply (Cont.) Checking Gas Connections

9

INSTALLATION

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We recommend that you install sediment trap in supply line as shown in Figure 13. 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. Do not over tighten pipe connection to regulator. The regulator body could be damaged.

CHECKING GAS CONNECTIONS CAUTION: For propane/LP gas, make sure exter- nal regulator has been installed between propane/LP supply and heater. See guidelines under Connecting to Gas Supply, page 8.

Pressure Testing Gas Supply Piping System

Test Pressures In Excess Of 1/2 PSIG (3.5 kPa)

1.

Disconnect appliance with its appliance main gas valve (control

 

valve) and equipment shutoff valve from gas supply piping sys-

 

tem. Pressures in excess of 1/2 psig will damage heater regulator.

2.

Cap off open end of gas pipe where equipment shutoff valve

3/8" NPT Pipe Nipple

Ground

Joint Union

Equipment

Shutoff Valve*

Natural Gas From Gas Meter (4" W.C. to 10.5" W.C. Pressure) Manual background

Propane/LP

From External

Regulator3" (11" W.C. to 14" Minimum Manual background

W.C. Pressure)

Figure 13 - Gas Connection

Manual background Pressure Regulator

Manual background Heater

Cabinet

Tee Joint

 

 

 

Reducer

 

Test

Bushing to

 

 

Gauge

1/8" NPT

 

 

Connection*

1/8" NPT

 

 

 

Plug Tap

 

 

Tee

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Joint

 

 

Sediment

Pipe

 

 

 

 

 

 

Trap

Nipple

 

 

 

 

 

 

 

Cap

 

 

 

 

 

 

 

 

 

 

 

 

was connected.

3.

Pressurize supply piping system by either opening propane/LP

 

supply tank valve for propane/LP gas or opening main gas valve

 

located on or near gas meter for natural gas, or using com-

 

pressed air.

4.

Check all joints of gas supply piping system. Apply a non-

 

corrosive leak detection fluid to all joints. Bubbles forming

 

show a leak.

5.

Correct all leaks at once.

6.

Reconnect heater and equipment shutoff valve to gas supply.

 

Check reconnected fittings for leaks.

Test Pressures Equal To or Less Than 1/2 PSIG (3.5 kPa)

1.Close equipment shutoff valve (see Figure 14).

2.Pressurize supply piping system by either opening propane/LP supply tank valve for propane/LP gas or opening main gas valve located on or near gas meter for natural gas, or using compressed air.

Equipment

 

Open

 

Shutoff Valve

 

 

*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 Accessory, page 30.

Closed

CHECKING GAS CONNECTIONS

Manual background WARNING: Test all gas piping and connections for leaks after installing or servicing. Correct all leaks at once.

Manual background WARNING: Never use an open flame to check for a leak. Apply a noncorrosive leak detection fluid to all joints. Bubbles forming show a leak. Correct all leaks at once.

Figure 14 - Equipment Shutoff Valve

Manual backgroundManual backgroundManual backgroundManual backgroundFor more information, visit www.desatech.com

110720-01C

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Desa VN10A installation manual Checking Gas Connections, Pressure Testing Gas Supply Piping System, Installation, Continued