Atwood 6 gallon water heater -- gas valve issues

[MR AIRSTREAM]

I have a 6 gallon Atwood water heater that developed a problem a few days ago and will not light.

When you turn on the water heater you can hear the gas value solenoid click (open I assume) and within a second you hear it click again (closed I assume) so no gas is present.

I have gas pressure, 12 volts and continuity thru both thermostats. As soon as the second click of the gas valve is heard the red light inside is illuminated.

Any help would be much appreciated.

Thanks.

[Jammer]

Is the ignitor sparking?

[MR AIRSTREAM]

Yes it is sparking.

[TG Twinkie]

Is the flame rod clean and positioned in the flame?
It most likely is positioned close to the ignitor.
Make sure you have good connections on the control board.

[cameront120]

It sound silly, but you may have lost the air gap in the tank. Release the pressure and give it a try.

[MR AIRSTREAM]

Released pressure in the tank but it made no difference.

[TG Twinkie]

There is no pressure sensing device in the water heater. Releasing the pressure only results in reducing the head of air. A head of air is necessary to prevent over pressurizing the system.
Think of what would happen if you locked the lid of your tea kettle to prevent it from releasing steam. While the water heater would not get to that extreme it will build pressure unnecessarily.
The proper way to establish the correct air head is to drain some water from the water heater. Then close all valves in the water system and turn on the pump or city water. Then open a sink hot water valve and let the water run until all air is out of the lines.