Glowworm Ultracom 30cxi boiler - Low water pressure

16 Feb 2012
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United Kingdom

I have a Glowworm Ultracom 30cxi combi boiler. Since last weekend the boiler has not been starting up due to low water pressure. I wake up in the morning and the boiler has not started and is flashing around 0.2 bar. I top up the pressure to 1.2 by opening the fill loop and it starts up again. It then works all day fine but again is showing low pressure the next morning.

Is there anything i can do or check ?

Any help would be appreciated.

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Hi there

if the boiler is losing pressure then there is either a leak somewhere, or water may be coming out of the overflow outside. Can you see any evidence of this?

Kind regards

No leaks but water is coming out the overflow. I also found a magnaclean filtration unit attached to the return on the CH pipework which hasnt been cleaned for at least 3 years. Could this cause a problem ? I will take apart and clean later anyway.



Then you have a leaking prv, and probably a knackered expansion vessel.

If you are going to open a magnaclean, do it before you buy the other bits, cause chances are, it'll leak or the isol valves will snap, so you can get a new one while you are out.
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