# Truma S3002 - main burner not firing. (1991 Hymer)



## Watoh (Dec 8, 2015)

Hi all,

I need a pointer or two or some shared knowledge!

My Truma S3002 heater (air) has stopped working.  Perfect time of year!

The pilot is lighting fine just the main burner is not firing.  Seemingly the value never opens.   I've stripped it out and taken it apart.  *now everyone take a collective breath and shake your heads* :scared:  I was hoping a spider or similar had blocked the jet, alas no, jet looks fine.

On speaking to my nearest Truma repair centre it seems it must be either the jet, valve or thermocouple switch.  My understanding of how the system works is:  Pilot fires, heats up the thermocouple which open the main value that feeds the main jet.

My nearest repair place cant look at it until end of January and is also completely freaked out that I have stripped it and dismantled it! And is not that happy about dealing with it, he might deal with it if I reassemble it and pay him to dismantle it!

I have found the following parts:

£12 THERMOCOUPLE TRUMATIC S3002






£91 - SAFETY PILOT VALVE COMPLETE TRUMA S3002





£52 - BURNER COMPLETE 30 MBAR FOR TRUMATIC S3002 OLDER MODELS






I'm pretty bloody poor right now so am looking for frugal solutions.  I doubt I'll get change from £300 from the dealer if i get him to fix it in January...

Basically I'm not sure what to do, and am looking for advice.    What should I do? 

Anyone know of any further testing i could do to track the issue down? 

(Don't worry, I promise I won't blame my future death based on your advice!  :angel: )


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## walpeter (Dec 8, 2015)

I had trouble with mine - also 1991 Hymer and discovered that the burner had disintegrated with age! I was in trepidation about what to do but did take the whole thing out in the end and replaced the whole burner including reconnecting all the other bits. My burner, by the way was designed for 50mb pressure so did manage to source one. I learnt a lot from research and from others on this forum and it's now working amazingly well - better than ever!!

I believe someone on the forum replaced the thermocouple (or the insulating sleeve) which did the trick so I would start with that.

Sounds like you have already removed the heater completely so once you have it out, everything else is relatively easy.

Good luck.


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## pgandt (Dec 8, 2015)

Had the same problem as yourself - I replaced the safety pilot valve and that fixed the problem.  Make sure you leak test before igniting the fire after you do any work


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## Watoh (Dec 8, 2015)

Thanks a lot for the swift responses.  The fact that two of you have had the same problem and fixed it by replacing different parts and the others suggest it might be the thermocouple is what i feared! I suppose if i can't narrow it down i'll get the the burner that comes with the thermocouple.

Regarding cleaning.. i stripped it to pieces, cleaned it a put it back together, with no improvement, so something has failed somewhere.



That's very interesting.. do you have a source for that 50mb set, all the ones i've seen are 30mb!


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## FULL TIMER (Dec 8, 2015)

Last one I had in (also in a hymer) the problem was with the burner unit, the gauze had rotted out and there was no way the main burner would light, looking at the bottom picture it's the long gauze on the right , the smaller round one is the pilot light, also worth checking out the gas pipe leading to the burner as I have known these to corrode and leak.


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## walpeter (Dec 8, 2015)

Watoh said:


> Thanks a lot for the swift responses.  The fact that two of you have had the same problem and fixed it by replacing different parts and the others suggest it might be the thermocouple is what i feared! I suppose if i can't narrow it down i'll get the the burner that comes with the thermocouple.
> 
> Regarding cleaning.. i stripped it to pieces, cleaned it a put it back together, with no improvement, so something has failed somewhere.
> 
> ...




Try ebay!


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## TJBi (Dec 8, 2015)

Have you phoned Truma's Technical people?  They're extremely knowledgeable and helpful.


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## martinmartin (Dec 9, 2015)

*truma fires*



Watoh said:


> Thanks a lot for the swift responses.  The fact that two of you have had the same problem and fixed it by replacing different parts and the others suggest it might be the thermocouple is what i feared! I suppose if i can't narrow it down i'll get the the burner that comes with the thermocouple.
> 
> Regarding cleaning.. i stripped it to pieces, cleaned it a put it back together, with no improvement, so something has failed somewhere.
> 
> ...



50 mb parts are available from liesure spares ltd.Is that what your regulater is.


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## Watoh (Feb 4, 2016)

Well pooh.

Finally got around to working on this, replaced the burner & thermocouple, and no difference.

Seems like it must be the main value assembly.


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