Baxi 105E temperature sensor

[Fozzy6550]

Hi,
My 105E developed a fault which indicated temp sensor fault (80 flashing)
I changed the sensor no problem but did not apply the heatsink paste as I did not have any. Initially the problem seemed to go away but has returned?
Could this be due to the lack of paste? If so, where is this applied..... To the threads or to the sensor terminals?
Any help would be appreciated
Thanks
Neil

 

[Agile]

If this is the dry pocket sensor then logic would say that you apply thermal paste to the nose of the sensor within which the NTC element is located.

But the instructions from the makers says that no paste is required !

Their idea must be that the time constant is adequate and deigned to be used without paste.

Perhaps either plus contacts may be dirty, or perhaps your new sensor has failed already.

But I never understand why so few people ( including RGIs too ) ever bother to measure the resistance of sensors, ideally at the PCB connector end so the cable and plugs are also measured.

Tony

 

[Fozzy6550]

Thanks Tony,

Having looked into this further by checking the manual schematics, I realised that I replaced the DHW sensor & not the CH sensor by mistake - the error code shows CH sensor faulty & I didn't realise there were actually 2 separate sensors!

I'll purchase another & replace ASAP then at least I know both are good.

Thanks anyway,

Neil