Vaillant ecoTEC pro 24 service code s.39

15 Oct 2004
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United Kingdom
Just had a Vaillant installed 2 weeks ago and all was working fine until it displayed a "spanner" symbol. Now it wont work with either heating or DHW.
The service code displayed on the lcd display shows S.39 which, according to the manual is 'Burner off contact has triggered'.
No fault code at all, but boiler wont work. I've tried a reset, and power off/on.
Obviously it's still under warranty, but why would it stop working with just a service code ? And how do i clear the service code ?

Many thanks.
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You need the installer to help you, not Vaillant at this stage.

The code means that an external interlock contact has been opened to stop the boiler working.

Do you have a pump to pump the condensate? If so has that become depowered so its not pumping?

Where is the boiler fitted?

Is there anything unusual about the installation?

Hi Tony,
I guess there is a condensate pump as a component bundled in with the boiler as default. I can see the condensate pipe feeding into the soil stack after about 2 metres.
Nothing unusual about the install although it is installed in the attic against an external wall.
Why are you not speaking to your installer who knows the installation rather than us who only know what you are telling us?

Its not so common to have a condensate pump.

Could the condensate outlet pipe be blocked or filled up with water because there is no slope in th pipe?

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I posted the issue on here for a wider viewing in case someone knew of a similar or known problem occurring on this particular boiler that could be fixed simply.

The slope on the pipe is about 20degrees, but yes, there could be a blockage.

My installer is coming back later in the week.
When your boiler is not working he should be round to you on the same day!

I am not impressed by him!
Do let us know what the problem was when you get it fixed; haven't heard of many problems with the latest Ecotec.
It's fixed now, apparently it was a loose connection on the PCB. I guess i'll have to take his word for it.

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