Webasto Thermotop C - question re servicing

iceboy

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Can anyone please help with a simple question about the Webasto Thermotop C 5.2KW diesel heater in my boat.
I am trying to diagnose a possible fault using the diagnostic software. I've emailed many places in the Webasto group with this question but never get a reply.

Question
What is the normal resistance you would expect the glowplug/flame detect to have when running normally under full combustion?
Consequently, what is the threshold resistance below which it is assumed to be detecting a burn out condition?

Thank you very much if you are able to answer my question


(Note: I am reading your replies and also sending my own back to you but the moderators are delaying my messages for 12-24 hrs, perhaps because I'm new)
 
Last edited:
Oh, 1.533 ohm !

Thank you, My diagnostics is showing about 1.6 ohm when the detector is glowing, but then it's nearly white hot, much hotter than under flame conditions. At full burn I'm getting between 0.513 ohm and 0.519 ohm which I am suspecting is too close to the threshold resistance value when the ecu decides there's been a burn out.

Using the software to log values every second I even saw the flame detect flag drop from 1 to 0, indicating a burn out, after 20 minutes at full load when the detector resistance had been steady at between 0.513 to 0.519 ohm all that time. In fact it was reading 0.519 at the time the ecu decided it had a burn out and turned the pump off.

If you're getting over 1.5 ohm under full load then my one is seriously low (for a heater only two months old)
 
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