Monessen Hearth CDVT33NSC7

[David Woodward]

Monessen Hearth CDVT33NSC7 not working for a few years, sparked but would not ignite, local heating company diagnosed faulty Pilot Assembly which they just replaced.
Now works but only ignites with back up batteries installed and power adapter disconneted.
They sugggest replacing the power adapter (Part # 80D0041) however I am getting 6 volts output from it.
Any thoughts or suggestions appreciated.

 

[DAKSY]

How many batteries & what size are the ones in the back up cradle?

 

[David Woodward]

How many batteries & what size are the ones in the back up cradle?

4 x AA

 

[DAKSY]

4 x 1.5 = 6vdc, so your power adapter’s output is not getting to the gas valve. Check the wiring & connections.

 

[David Woodward]

Wiring looks ok that I can tell.
The ignitor / Sparker cable goes to the Pilot Assy from the Control board which should be powered by the 6V AC Adapter, however although 6V Adapter is connected to a 120V power source and appears to be giving 6V out, the Control board is seemingly only powered by the 4 x AA batteries in the Command center module.
That I see, any wiring issue to the Pilot Assy would result in the fireplace not even working on battery backup power. See page 38 on manual.

 

[DAKSY]

I think you might want to remove the control board & have it tested at your local dealer. They should have test boards set up for checking components of their fireplace systems.

 

[David Woodward]

Thanks for the suggestions, it looks like it was the 6V power adapter after all, voltage was correct (as measured with a meter) but it just wasn't supplying the current. Have a 5V 2 Amp adaptor hooked up currently as a test (Don't have a 6V adapter lying around) and it appears to be working fine.