worcester 24CDi pressure increase

[imitch]

Hi all,
my ch system is ten years old and have had no problems until now. the pressure increases slowly even when heating is off (overnight) from 1 to 2.5 bar. It's a closed system and i think mains water is getting in as when draining the rads to relieve pressure the water is bubbly/oxygenated. Also when the hot tap is running the radiators heat up and vice versa. The filler key has always been out (in my toolbox) so the waters getting in some other way. from other posts the heat exchanger has been mentioned in similar problems.....sound right?
thanks

 

[pannierstan]

You need a new water to water heat exchanger (calorifier)

Stan

 

[scatmanjohn]

Sounds like you need a new water to water heat exchanger and the diverter valve needs looking at.

 

[imitch]

thanks for the info guys
cheers

 

[Agile]

That can cost money!

( Said in a Scottish accent with a sucking in of air between the teeth! )

Not so much if you can fit it yourself though, perhaps less than £50 to buy!

Its very odd, this is a VERY rare failure on boilers in general but I have had to change two on Worcesters but none in general work on other models!

Tony

 

[Slugbabydotcom]

Its very odd, this is a VERY rare failure on boilers in general but I have had to change two on Worcesters but none in general work on other models!

Tony

Same here! 2 Worcesters and none on any other make