Water in expansion vessel, Worcester 280 rsf

[jotto]

Whilst trying to diagnose my hot water problem, wife screaming cos the shower keeps going cold! Found I had water in the expansion vessel which I realise is a bad thing! lol.

Would water in the vessel cause the DHW to cycle on and off?

What pressure should the new one be charged to and will it already be pressureised?

Read FAQ about changing it. Isolate heating from boiler, drain boiler and leave drain open. Fit new vessel and check pressure in it and adjust as required. Close drain. Refill sysytem.

Would it be worth completely draining the CH side of things as well or would this open up another can of worms?

 

[gas4you]

Check/set the pressure in the new EV before fitting.

Could be related to fault or a complete seperate issue.

 

[GasMan1965]

I reckon separate issue !!

 

[jotto]

I reckon separate issue !!

Such as?

 

[GasMan1965]

Poss faulty thermistor but could be a variety of things really,, heat exchanger could be scaling , diverter ..

 

[jotto]

Poss faulty thermistor but could be a variety of things really,, heat exchanger could be scaling , diverter ..

OK, so the thermistor, is that the temp senso on the heat exchanger pipe?

Heat exchanger scaling, possibly but we live in a very soft wter area and Ive yet to see any build up of limescale etc in any of our kettles or washing machine elements when they have needed replacing.

Diverter valve appears to be fully operational, lever moves as it should.

Any ideas what sort of resistance the thermistor should be at various temperatures? Should be able to check if I know what the temp is.
Thanks in advance.

 

[gas4you]

I would take one step at a time and get the EV sorted first. Once this is out of the way then put your energy into diagnosing the other possible fault if it remains.

 

[jotto]

I would take one step at a time and get the EV sorted first. Once this is out of the way then put your energy into diagnosing the other possible fault if it remains.

Sounds good. Will try to pick up a new EV tomorrow.

Cheers!

 

[clf-gas]

Readings for hot water sensor are between 1.5 and 25 kohms when cold.
Check the flow switch aswell.

 

[jotto]

Not too sure how this forum works but just in case any of you guys are watching this thread or have subscribed to it, have started this new thread.
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