Worcester Green star 37cdi Pressure loss.

[Geoff1946]

Why are you taking up the floor now, when it sound like you've narrowed the leak to the boiler? Unless you are dead unlucky you won't have TWO leaks.

 

[UNG]

Have seen a problem similar to this on a Worcester boiler a few years ago and it took a while to identify the exact location of the leak

In the end after a bit of patience and an inspection camera looking at where I thought the fault was I found a very very tiny leak from the top of plastic fitting that connects to the heat exchanger on the right side of the boiler. This leak was so slight I only noticed it because a tiny spec of dust started swirling round in the hollow on the top of plastic fitting where the leak was swapped the plastic fitting and all was good, part cost about £30

 

[Bruspark]

Unless you really like pulling floors up I'd have turned off the boiler, closed isolator valves (or removed and  linked the boiler flow and return pipes) with a gauge in line and pressurised that arrangement to 2 bar.   If it held its not the external piping

Otherwise/then close/cap the boiler return put 2 bar into the flow and again pressurise and check.  remember that a leak inside the combustion chamber can exit invisibly  down the condensate drain 
Don't over think it - just narrow it down !! 

 

[Alser]

To be honest, just don't know which way to turn now. Is boiler beyond repair?,I don't know for sure.  You rely on gas engineers to give you the answers but it seems that, and especially more with lockdown and the present below zero conditions that it's a quick in and quick out to the next job without any thorough investigation.

I have no wish to tar everyone with the same brush but it just seems to be the way of it and as a layman you can only rely on the information you are given and engineers to 100% find the problem.

  So, what am I to do, phone another company out and pay more call out charges  I did try re-contact company that came out yesterday but phone ringing out.

I did remove the outer case this morning to see if inside was wet again but was dry inside.  Boiler pressure had fallen back to zero. Pressured up to 1 bar.  Reset boiler but would not kick in,  and no green light. 

Temps have consistently over the last 10 days been minus 3 to 6, could this be an issue?

I accept there's a likely leaking pipe issue under floor and had started to lift flooring at one end but have stopped and will wait for weather to turn.

 

[Alser]

Unless you really like pulling floors up I'd have turned off the boiler, closed isolator valves (or removed and  linked the boiler flow and return pipes) with a gauge in line and pressurised that arrangement to 2 bar.   If it held its not the external piping

Otherwise/then close/cap the boiler return put 2 bar into the flow and again pressurise and check.  remember that a leak inside the combustion chamber can exit invisibly  down the condensate drain 
Don't over think it - just narrow it down !! 

Just worked out how to quote, dah!  forgot how to.

Isolating valves was mentioned way back at start of topic, just wasn't sure exactly whether I should shut off all 4, have mobility issues and struggled to get under and shut all 4 off but managed okay.

I'm assuming I now wait to see if pressure drops over a period of time? and if stays at same pressure, it is not a boiler leak issue?

 

[Geoff1946]

Just worked out how to quote, dah!  forgot how to.

Isolating valves was mentioned way back at start of topic, just wasn't sure exactly whether I should shut off all 4, have mobility issues and struggled to get under and shut all 4 off but managed okay.

I'm assuming I now wait to see if pressure drops over a period of time? and if stays at same pressure, it is not a boiler leak issue?

If the gauge is on the boiler, (which is the normal arrangement), then it's monitoring the pressure in the boiler and if it still falls with the isolator valves shut then that's where your problem is; i.e. within the boiler. 

If, as you said earlier, there is water inside your heat exchanger casing, and going down the condensate drain, then there is little doubt in my mind that's where your problem lies.

Note the other post, recently, which talked of a leaking plastic coupling to the HE. Yours just might have been disturbed by the guy who fitted a new pressure vessel, and could be a simple fix.

CONVERSELY, if the pressure of the isolated boiler holds up OK, then open the isolators to the heating circuit, (the larger 22mm pipes), and if the pressure THEN falls it must be via your pipework.

The other valves, (almost certainly 15mm), are not really relevant to your issue, being the gas supply, the mains water input, and the hot water out.

 

[Alser]

So Folks,  the latest update!,  pretty sure you will have had your fill of this topic but here goes;

I phone same company this morning, explain the issue,  guy sends the same  engineer out again.  Pressure is at zero.   Pressures it up to1\12.   I mention to him Geoff's suggestion regarding the possible split in the plastic fitting and he says it is fine. He then takes the condensate trap out, takes pipe off and a good amount of water runs off, perhaps a litre or two.

He then blows through the pipe and says it was blocked and he's cleared it, he's now 100% sure that was the issue. 

      Powers up boiler and!  Happy Days!!  Heating and Hot water again.    I check boiler 10 mins later and notice a constant drip coming from somewhere inside. I get myself underneath and notice that he has not refitted the hose retaining clip correctly to the trap.

Anyway, managed to fix myself and so far so good, fingers crossed.

Still watching out for pressure drop though and possible pipework issue.

So really mean it folks, A big shout out to everyone who has taken time out to reply to this post and I hope that it will be of benefit to others in the future.

    Thanks again.

 

[Sharpend]

Thanks for feedback, although I’m not sure how a blocked pipe leads to pressure loss? But here’s hoping. 

 

[Bruspark]

Blocked condensate drain normally raises an alarm but un-blocking it is never a bad thing.   

There is no mechanism I can think of where a blocked drain leads to pressure loss . . If it happens again I'd ask them to send a heating engineer next time  . .

 

[Murdoch]

The MIL's boiler often stops working during very cold weather - the fix is to poor hot water over the condensate pipe outside - once the ice has gone the boiler will operate properly again

 

[Alser]

Hi again,  Situation is that Im having to have boiler on two or three times daily only, enough time to get showered and get some heat in the house for a while at least,

 I am aware that boiler is goosed, heat exchanger fault, ( hot water flowing down condesate pipe when boiler is on) and also a possible under floor pipe leak,  boiler needs to be re-pressurised after around 30 min.

Just trying to coax boiler through another few months until funds allow for a new boiler but at least Ive got heat and hot water for a time,

        Cheers

 

[Geoff1946]

Glad to hear that you at least know where you stand now.  For what it's worth I doubt if you will have a second leak in your system, as that would be REALLY bad luck. However, when you are having the boiler changed a competent plumber can pressure test your system to put your mind at rest. Depending on condition, flushing might be a good idea too as would fitting a magnetic trap to protect your new boiler.

 

[Sharpend]

 Competent being the word.