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Ariston EuroCombi loosing pressure

Postby novicehere » Fri Nov 26, 2010 3:35 pm

Hi, I seem to have an unusual problem with a 10-year old EuroCombo Ariston boiler.

Last Friday, the "Low System Water Level" indicator on the Boiler came on without any warning and stopped the boiler. I shut down and restarted the boiler and it seemed to work fine again - until the next morning when it tripped the boiler again.
I noticed the pressure was quite low and increased it to see if it would fix the problem..

In spite of the increased pressure, the indicator kept on tripping throughout the day and the weekend (almost every 2-3 hrs) we finally got the BG engineer in who said that the problem was a faulty "pump flow" switch which he replaced on Wednesday. He also increased the pressure to 2bars, I believe.

The CH and hot water have been working fine since then.

Yesterday (Thursday), I noticed that the pressure was down again to below 0.5 and so I increased it to just above 1 (when boiler was cold).

Today morning (Friday), I noticed it had fallen almost close to zero.

Strangely the CH and hot water are working fine and there are no apparent leaks in any of the radiators as far as we can see.

The pressure rises to around 1 when the boiler is on.

Any clues as to what might be happening? I dont want the CH/ hot water to stop before asking for help.

Thanks a lot.

The mains pressure in our area is very good.

I also read on some of the posts about checking for a leak in the external pipe. The boiler is in a cupboard that might have had a pipe going outside but the other side oif the wall now has an extension and so no pipe is visible.


Separately, I have had water leaking due to worn out reseal and flow switch washers twice in the last 8 weeks. Before that I had to replace some more washers (dont know which since job was done by British Gas) in June too. I know this may be a stupid question but this cannot be linked to the above, right?
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