Grant euroflame condensing oil boiler losing pressure

[Astra]

Hi all,

Hope you might be able to help.
Last year I installed a new boiler as per title.
Since then the pressure is always very low to none and I have to constantly top it up.
The system was fed from a tank in the attic and had very low pressure, at best 0.4. I had it swapped it to be fed from mains and the pressure now is healthy enough at 1 when not working and nearly 2 when it's running; that is when the system is full with water.

I topped it up again yesterday as it was low. Today, I just happen to be on the side of the house and the condensing trap was dumping a lot of water. I cant tell exact quantity but It was a solid stream out of the pipe for at least 30-40seconds.then I looked at the pressure and it was back to 0. I had seen this happening two more times, but I never really put two and two together.

From what I ve managed to read, my expansion vessel might be toast? I don't have much experience with these things, but after three plumbers and a full leak test I am trying to figure out myself.

Can anyone help make some sense? Many thanks

 

[SimonG]

Need to find yourself a decent plumber. Not a hard job to find the issue. What size system is it?

 

[Astra]

Thanks, it's 34kw. Do you have any pointers maybe as I am not having too much luck with the plumbers.

 

[SimonG]

How many radiators etc rather than boiler kw rating.

When was it last serviced?

 

[Astra]

How many radiators etc rather than boiler kw rating.

When was it last serviced?

There are 16 radiators, one floor, bungalow. it has been installed new in February so hasn't needed a service yet.

 

[John.g]

Did any of the three plumbers check the E.vessel air end pressure when the pressure fell to 0.1 bar?. If that was/is still 0.7 to 1.0 bar or so then the E.vessel is OK. Also the boiler should be pressure tested isolated from the rads in view of getting all the water from the condensate trap, the boiler, if proven leaking, should be under warranty?.

 

[Astra]

Thanks for the reply, nope, noone checked that and they haven't done any pressure testing on the boiler either. I had called the place I bought the boiler from and they keep telling me that if I keep losing pressure it's because I have a leak in the system.

 

[John.g]

If the water is still leaking from the trap with the boiler off then I think that you will have to get the boiler tested on its own even though it's a practically new boiler.

 

[Astra]

Thanks, I am going to call them again and hope for the best.

 

[SimonG]

Who fitted the boiler last year?

 

[George E.]

Is your expansion vessel within the boiler case. Or external. The one provided with the Grant boiler has a capacity of 12 litre. With 16 rads you may require a larger one. As the water gets hot it expands =increased presure. If presure goes above 2.5bar the PRV will operate and discharge water out a pipe to outside. Are your rads single or double? If large double It would excede the total 128 litre total capacity of boiler with only the 12l tank.
See what size of tank you have.
And also is there any discharge from the PRV pipe?

 

[Ben-gee]

Why won’t this thread go away?!

I’ve read it yet it remains in bold and comes up as a new post?

It’s the only one to have done this?

I’m interacting with it to see if it will go...
[automerge]1568963084[/automerge]
Yes that did it!

Bizarre.

 

[SimonG]

I received a notification this morning re a reply just after midnight. But nothing there.

 

[Astra]

Boiler was fitted by a company in Dublin. The vessel is external, 8lts I think.

 

[SimonG]

Not big enough, needs a bigger vessel.