WORCESTER BOILER BLOWOUT

[ianblue]

Boiler blowout . Went over 3 bar blew out discharge.
Boiler man came blew up pressure in expansion vessel. Waited 20mins or so pressure steady at 1.5bar.
Over next few hours pressure increases gradually to 3bar.
What is possible cause?

 

[joe-90]

One cause is the expansion vessel filling with water. You can compress air but not water.

 

[Corgigrouch]

Boiler blowout . Went over 3 bar blew out discharge.
Boiler man came blew up pressure in expansion vessel. Waited 20mins or so pressure steady at 1.5bar.
Over next few hours pressure increases gradually to 3bar.
What is possible cause?

If it's a combi, then possibly the plate heat exchanger is holed and passing from DHW to heating. If it's a system boiler, then leaking coils in the cylinder..

 

[bengasman]

Does the pressure increase with the heating on or off/
Did you remove the filling key/loop?

ps
Just ignore Joe, he likes to pretend he knows about this, but he is just a noob.

 

[joe-90]

But you know he's right.

 

[ianblue]

Thanks Joe for the elementary physics lesson. I don't mean to be demeaning but I learned that in prep school.

Bengasman you were spot on with your loop question. Unfortunately whoever installed the boiler only put one valve in at one side of the loop, hence it could not be removed.
The clever boiler engineer checked that first, fitted a new valve in series with the leaky one, then left, leaving the new new valve turned on!
Luckily I spotted that and closed the valve. So fingers crossed I won't hear any more calls from the tenant.

 

[joe-90]

prep school.

/quote]

 

[BingoBongo]

Untitled

• BingoBongo
• 4 Nov 2009
• 2

 

[joe-90]

Oh dear. Wot a saddo.

 

[muggles]

Oh dear. Wot a saddo.

Looking in a mirror there Joe?

 

[joe-90]

I aint sad.

 

[muggles]

Just incredibly irritating then...

 

[joe-90]

I can handle that!

 

[muggles]

Clearly

 

[Agile]

In many cases that senario originally described results because the engineer does not reduce the system pressure to zero before repressurising the air.

In fact as far as I can see the majority of BG engineers only top up the air without depressurising. That saves them a lot of time and usually cures the problem for the time being but is not the correct way to do it.

Tony