Worcester 24cdi pressure gauge reacting slowly

[Neil1976]

I've had some very confusing behaviour out of my Worcester 24cdi. It seems to be functioning normally in terms of heating and hot water, but recently I tried to add a little pressure (it had dropped slowly over a long period) and the pressure didn't rise, even though I could hear the inflow of water. Some days later I noticed the pressure had belatedly risen (and kept rising slowly over ensuing days). I was baffled and decided to try to lower pressure a little. I let a couple of litres of water out of a radiator, but the needle on the pressure gauge didn't budge. Again, the next day I noticed it had finally gone down. I haven't heard any reports of faulty gauges on forums, but I don't know of any other faults which would cause this behaviour. Also, when heating comes on, pressure doesn't raise. In the past (> 6 months ago) the gauge always behaved normally (jumped up quickly when heating came on, or when I added water via the inflow, and dropped quickly if I took water out of system). I don't want to tamper with it while the weather is so cold (and it is heating okay), but wondered if anyone has any ideas?

 

[gasmick2]

Hi on these early 24cdi s the hole in the gauges got bocked up easy where it enters the primary pipes because it was very small// on the repacement ones its 3 times the size
so you need to replace it this will need draining down of the boiler

mick

 

[Neil1976]

Thanks a lot Mick. I presume that it is a relatively simple task to replace the gauge?

Neil

 

[bengasman]

also an indication that your system needs cleaning.

 

[Neil1976]

How do I clean the system?

 

[gasmick2]

Hi the best way is a power flush but does not come cheap but in the long run the system and boiler parts will last a lot longer for instance the plate heat exchanger and the main heat exchanger they would cost a lot more than the power flush
as far as the gauge is you will have to drain the boiler and disconect it from the pipes and make sure you seal it properly


mick

 

[Neil1976]

Thanks a lot for your advice. I'll get a power flush and replace the gauge.

 

[doitall]

Would be a damn site better to get a magnaclean TwinTech fitted instead.

£150 quid ish against £300-400, and it's a one off job, whereas a powerflush certainly isn't.

In fact draining the system out and doing both jobs at the same time is an easy DIY job.

 

[Neil1976]

Thanks for the suggestion. I'm a bit cramped for room (pipes are boxed in), but if there is room to fit one I'd certainly rather do that than pay for a power flush.