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maxim naumov
 
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Default combi boiler questions

Ed,

replacing the DHW temperature sensor helped !

the original sensor still had variable voltage drop on it, but I think
the problem was as follows: the sensor consists of several parts. one is
the external housing, made of metal. inside there is the actual sensor
and leads, kept in place by some sort of plastic or epoxy.

___-__
+----+\_____
====|XXXX! _____| this side is immersed in water
+----+/
---_--

I noticed that with my old sensor, the internal part was a bit loose in
the housing (epoxy shrunk ?), which was perhaps causing bad heat
transfer to the sensor. maybe the semiconductor has degraded with age, I
don't know. the sensor was testing ok with an ohmmeter.

now after replacing it I can enjoy shower without boiler cycling, given
that the mains pressure is sufficient. most of the time it is. when it
is not, I just feel that the flow is weak.

thanks for your replies !

/max