[TheMask]

Combi losing pressure but theres no leaks..

[woodbush]

You need seacam, just bump the thread when he is online.

How can you tell there are no leaks, isn't the pressure gauge for the radiator system. It doesn't take much for the pressure to drop.

[Andykel]

How can you be sure there's no leaks? :P

Check your pressure relief pipe for water coming out of it also.

[TheMask]

Sorry just bumping my thread as Seacam will be here soon..

[seacam]

Originally Posted by TheMask

Sorry just bumping my thread as Seacam will be here soon..

Hi Mask,

OK combi loosing pressure, what combi, brand and model, how old, how old is the rest of system, house or apartment? ( what floor? ).

When was it last serviced?

It's working, just loosing pressure is it?

I'm all over the place on forum's today, If I don't reply straight away, I've not forgotten you and you may be given the answer mean while.

But to be getting on with, with some tissue go round all the rads', wipe a bleed nipple, check tissue for water, same on each rad valve around joints, check each one, check tissue each time for water,----anything? and if so tighten.

That's the easy bit.

[TheMask]

I have done the bleed nipples and valves

the boiler is a Worchester greenstar 24i or 28i and its 2 years old..had no problems what so ever its on the ground floor of a two story house..i run 8 rad and a shower of it

the boiler works fine its just the pressure

thanks

[TheMask]

would the shower make a difference ?

[seacam]

Originally Posted by TheMask

would the shower make a difference ?

Hi Mask,

Yes but not with the loosing of pressure.

How often is the pressure dropping?

Take a gulp, ---if it's not a faulty gauge and pipe work/system is not leaking, then pressure relief valve-vent needs to be checked.

Or very possibly a faulty, leaking heat exchanger.

This is a known problem, not a common one on the 24s and 28s.

Out of warranty or not, serviced recently or not argue your case with installer or Bosh.

If faulty heat exchanger, they fix FOC or you sue, HEs should last a hell of a lot longer then that.

Hopefully, it's a small leak or the PRV.

[TheMask]

Ok i think i found the problem..The boiler wes blowing off out side...I didnt even know what the noise was..So after further investagation at the side of the house where i hardly ever go the boiler was constantly blowing off.

I checked the water make up they were closed and all seemed well but I could hear the water running...I found that the make up valve wes passing...so new valve fitted and the boiler has stopped blowing off outside and the pressure has stayed at 2 bar now for a while.

I cant see how this would cause the pressure to drop though as the boiler was constantly making up.

can you explain this Seacam

thanks for your help

[seacam]

Originally Posted by TheMask

Ok i think i found the problem..The boiler wes blowing off out side...I didnt even know what the noise was..So after further investagation at the side of the house where i hardly ever go the boiler was constantly blowing off.

I checked the water make up they were closed and all seemed well but I could hear the water running...I found that the make up valve wes passing...so new valve fitted and the boiler has stopped blowing off outside and the pressure has stayed at 2 bar now for a while.

I cant see how this would cause the pressure to drop though as the boiler was constantly making up.
can you explain this Seacam

thanks for your help

Hello Mask,

Yes, this is the PRV, ( Pressure Relief Valve ), I mentioned.

There is a paragraph missing from my post, advising how to check for a leaking PRV pipe or problem if it wasn't obvious, yours clearly is.

There are several causes for the vent pipe to discharge, a faulty expansion vessel, ( diaphragm leaking ), one that needs charging, a faulty PRV, or a faulty heat exchanger, this is where mains water pressure forces its self through the HE then the discharge pipe.

In both scenarios, symptoms are similar.

When you mentioned yours is the Worcester 24i, there is a know but uncommon fault, with a leaking heat exchanger.

Having first checked no leaking TRVs and bleed nipples, having checked as best as I could no leaking pipes or the EV needs charging, then my next suspects, would be a faulty HE and/or a faulty PRV.

A faulty PRV is an easy fix and I would eliminate the EV needs charging before delivering the news that it is either a leaking EV or HE both of which would be expensive to fix.

If you wish I could explain further why the vent pipe discharges, suffice to say if a PRV wasn't in existence along with a couple of other safety features including an EV, your combi would have no wall to be hung off or no roof to the property for that matter.

[TheMask]

Hi Seacam

Im all sorted now

Thanks

[seacam]

Originally Posted by TheMask

Hi Seacam

Im all sorted now

Thanks

What was the problem?

[Andykel]

Originally Posted by TheMask

Sorry just bumping my thread as Seacam will be here soon..

My post not good enough?

But as I thought, it was coming out of your relief pipe.

I'm guessing your expansion vessel was needing charged?

[TheMask]

Originally Posted by seacam

What was the problem?

The engineer came out.

No 1..the make up valve was passing so he replaced that ...That stopped the boiler blowing off out side as it was constantly making up.

No 2..With it making up all the time it had caused the pressure relief valve to lift ..well thats how he explained it to me. So he changed that.

What ever he did fixed the problem...I haven't lost pressure since.

Originally Posted by Andykel

My post not good enough?

But as I thought, it was coming out of your relief pipe.

I'm guessing your expansion vessel was needing charged?

Yes your post was appreciated and I checked what you said and it was blowing of as you said. I haven't a clue if the engineer charged the vessel as I just left him to it.

This was all done free of charge


Thanks for the help Seacam..Andykel

[seacam]

Originally Posted by TheMask

The engineer came out.

No 1..the make up valve was passing so he replaced that ...That stopped the boiler blowing off out side as it was constantly making up.

No 2..With it making up all the time it had caused the pressure relief valve to lift ..well thats how he explained it to me. So he changed that.

What ever he did fixed the problem...I haven't lost pressure since.

Yes your post was appreciated and I checked what you said and it was blowing of as you said. I haven't a clue if the engineer charged the vessel as I just left him to it.

This was all done free of charge

Thanks for the help Seacam..Andykel

No worries and glad to hear it's all sorted Mask, --------------make up valve,-----that really is quite wonderful.

[TheMask]

Originally Posted by seacam

No worries and glad to hear it's all sorted Mask, --------------make up valve,-----that really is quite wonderful.

Have I used the wrong words....is it not called the make-up valve..its the one you open under the boiler to top it up...

Seacam does what he did sound right to you..or should I expect future problems..?

[seacam]

Originally Posted by TheMask

Have I used the wrong words....is it not called the make-up valve..its the one you open under the boiler to top it up...

Seacam does what he did sound right to you..or should I expect future problems..?

Hi Mask,

There are such things as makeup valve kits, your mis-understanding made me chuckle.

It's right because your system is working, it as I thought the problem might be.

Not very helpfull this but always allow for problems but at least your boiler is more reliable then many, enjoy.