In article ,
charles wrote:
Old boilers (or rather CH systems) still have things like pumps and
valves which can and will fail eventually. No different from a modern
one.

I suspect that part of the problem is caused by the slightly complex
control circuitry. This is operating in a somewhat hostile environment
for electronics and tends to be the main cause of failure. (Lead-free
solder probably doesn;t help the reliability)

On my Viessmann, the PCB is sited at the bottom of the boiler. And runs at
near enough room temperture. A decent modern boiler produces very little
heat into the room anyway. A far less hostile environment than the average
car ECU. And probably better than the average PC, or PVR, etc.

--
*No word in the English language rhymes with month, orange, silver,purple

Dave Plowman London SW
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