To Replace Gas Valve (See burner illustration on page 10)

1.Discontinue power to dryer.

2.Close shut-off valves in gas supply line.

3.Disconnect gas valve wiring.

NOTE: Identify location of each wire for correct reinstallation.

4.Break union connection before gas valve.

5.Loosen and remove four (4) screws securing pipe brackets to burner.

6.Remove valve and manifold assembly from dryer.

7.Remove valve mounting bracket, manifold and piping from gas valve.

8.Reverse procedure for installing new gas valve.

WARNING: Test all connections for leaks by brushing on a soapy water solution. NEVER TEST FOR LEAKS WITH A FLAME.

To Replace Main Burner Orifices

1.Refer to "To Replace Gas Valve" and follow steps 1 through 6.

2.Unscrew main burner orifices and replace.

NOTE: Use extreme care when removing and replacing orifices. These orifices are made of brass and are easily damaged.

3. Reverse the removal procedure for reinstalling.

NOTE: Test all connections for leaks by brushing on a soapy water solution. NEVER TEST FOR LEAKS WITH A FLAME.

To Test and Adjust Gas (Water Column) Pressure

There are two (2) types of devices commonly used to measure column pressure. They are spring and mechanical- type gauges and manometers. The spring and mechanical-type gauge is not recommended, because it is easily damaged and not always accurate. A manometer is simply a glass or transparent plastic tube with a scale in inches. When filled with water and pressure applied, the water in the tube rises showing the exact water column pressure.

NOTE: Manometers are available from the factory by ordering ADC P/N 122804.

1. To test gas water column (W.C.) Pressure:

a. Connect water column test gauge connection to gas valve pressure tap (1/8" NPT). This pressure tap is located on the outlet (manifold) side of the valve.

b. Start dryer. With burner on, the correct water column reading in inches would be:

Natural Gas - 3.5 Inches Water Column

L.P. Gas - 10.5 Inches Water Column

2.To adjust water column pressure (natural gas only, L.P. gas must be regulated at source):

21

Page 25
Image 25
American Dryer Corp AD-95 service manual To Replace Gas Valve See burner illustration on, To Replace Main Burner Orifices