Heater problem (will not ignite)

[presto]

Sorry I realized I posted this in the wrong section so I moved it here

Hello All

I hope someone can help me with this or offer some suggestions
I have a Minimax plus 200m pool heater with a VS820C gas valve
The pilot will light and stay lite but the burner will not fire
I jumped the TH/PP to the TH and the burner lights
as soon as I remove the jumper it goes back out.
So I am assuming the gas valve is still good? Any ideas as to what I should check next?
I have access to a multi meter if needed

Thanks

 

[ps0303]

You could check the pressure switch and see if that's it. How clean is the filter?

 

[presto]

I have a DE filter that was just back washed with new earth added
the pressure gauge is reading around 10

My big problem is I have no manual or anything (came with the house) for the heater so its all a guess
I cant seem to find anything online for my exact heater either

It says Hercules Products millivolt heater on the outside
inside says minimax plus millivolt purex pool systems
model 200 M

 

[ps0303]

This might help you.

https://www.parts4heating.com/v/vspfiles/images/pdfs/MiniMaxPlusPowerMaxIG.pdf

 

[presto]

Thanks
Mine is similar to that except I have no indicator lights or fans
but I am sure some of the parts are very similar