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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Plumbing Questions >> Baxi Boiler 105e https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1125001677 Message started by tubbies74 on Aug 25^th, 2005, 9:27pm

Title: Baxi Boiler 105e
Post by tubbies74 on Aug 25^th, 2005, 9:27pm

Can someone help me please I have had my baxi combi boiler installed 3 years now and all of a sudden the bar pressure keeps rising and releasing out of the outlet vale can anyone tell me why this is happening and what I can do to stop this happening all the time as it never happened before?

Title: Re: Baxi Boiler 105e
Post by thescruff on Aug 25^th, 2005, 10:19pm

Assuming the filler loop is disconnected, then the expansion vessel has lost it's charge or duff.

Title: Re: Baxi Boiler 105e
Post by tubbies74 on Aug 25^th, 2005, 10:26pm

the filler loop is connected

Title: Re: Baxi Boiler 105e
Post by thescruff on Aug 25^th, 2005, 10:41pm

Disconnect it then and check if it's letting by

Title: Re: Baxi Boiler 105e
Post by tubbies74 on Aug 25^th, 2005, 10:45pm

what do you mean by letting by? sorry to sound thick and all that

Title: Re: Baxi Boiler 105e
Post by chrishutt on Aug 25^th, 2005, 10:53pm

He means allowing water to pass through. If you disconnect the flexible hose bit, no water should emerge other than the water already present in hose.

Title: Re: Baxi Boiler 105e
Post by tubbies74 on Aug 25^th, 2005, 10:55pm

thanx I will try that and get back to you tomorrow with the result will you be here if I need further help what happens if the expansion vessel has lost its charge?

Title: Re: Baxi Boiler 105e
Post by billythekid on Aug 25^th, 2005, 11:40pm

if its not the filling loop, check the expansion vessel, they are usually re-charged with a hand pump, like the one you blow up bike tyres with.

btk

Title: Re: Baxi Boiler 105e
Post by thescruff on Aug 25^th, 2005, 11:57pm

wrote on Aug 25^th, 2005, 10:55pm:

thanx I will try that and get back to you tomorrow with the result will you be here if I need further help what happens if the expansion vessel has lost its charge?

Yep we're addicted to here ;D

Title: Re: Baxi Boiler 105e
Post by tubbies74 on Sep 1^st, 2005, 8:06pm

I have removed filler loop and there is no water other than that which was in the tube so it is letting by, where do I find the expansion vessel ? when I put the heating on the dial goes up two bar, is this dangerous ? I have been told its not and that the pressure will be released via the valve and overflow

Title: Re: Baxi Boiler 105e
Post by thescruff on Sep 1^st, 2005, 8:24pm

wrote on Sep 1^st, 2005, 8:06pm:

It's only dangerous to the heating system and will rot the rads out if you continue to introduce fresh water.

The expansion vessel will be shown on the manufacturers installation book.

Email me if you want a copy and I will try to recover a copy from my cd

Title: Re: Baxi Boiler 105e
Post by tubbies74 on Sep 1^st, 2005, 8:45pm

yes please also how do I pump it up if thats what is needed

Title: Re: Baxi Boiler 105e
Post by tubbies74 on Sep 19^th, 2005, 5:33pm

still building pressure can anyone help done the filla loop thing still no joy????

Title: Re: Baxi Boiler 105e
Post by chrishutt on Sep 19^th, 2005, 11:12pm

If the system pressure is continuously increasing, there must be mains pressure water entering. If it's not via the filling loop, it might be via a leak in the secondary heat exchanger.

Title: Re: Baxi Boiler 105e
Post by tubbies74 on Sep 20^th, 2005, 8:11am

Can you explain at bit more and how I rectify this thanks for your help

Title: Re: Baxi Boiler 105e
Post by CWatters on Sep 20^th, 2005, 9:39am

If you are sure it's NOT the expansion vessel or filler then...

I've just been through a similar problem. In our case the pressure of the mains coming into the house increased to 5 bar and that caused the 3 bar relief valve on the boiler input to open. The first we knew about it was a £700 water bill.

To confirm the problem add a pressure guage to the mains input to the house.

The solution in our case was to fit an adjustable (1-4 bar) pressure regulator just before the boiler relief valve. Set it to say 2.75 bar. It helps if you add a second pressure gauge after the regulator so that you can adjust it accuratly.

This cured the problem for us but introduced a minor irritation... The pressure regulator isn't a very good regulator. Sure it always stops the pressure exceeding the set value BUT it also reduces the flow rate when the taps are on. With the hot taps off the pressure is the set value (eg 2.75 bar) but as soon as you open a tap it falls to 0.75 bar. The new regulator is clearly the problem because we didn't have this problem before fitting it. I've tried two different makes with little real improvement.

PS Any flow through the filler will increase the pressure. Be really sure that it's not allowing drips through. Let the filler pipe drain into a bucket overnight and see if it's still dripping the following day.

Title: Re: Baxi Boiler 105e
Post by CWatters on Sep 20^th, 2005, 10:50am

I've thought of another possible cause..

It could be a leak between the primary and secondary inside the boiler itself. In effect a hole between the two parts acting like another filler. Not sure how to diagnose this.