New combi boiler - pressure too high

suzyq2909

Hi, does anyone have any ideas/suggestions as to why the pressure on my brand new combi boiler keeps climbing into the red zone. I'm paranoid I'm going to come home one day to find a hold where my house used to be.

The heating and hot water are both working perfectly fine, but the plumber who installed it said the pressure guage should be within the green zone (1-2 I think) but mine keeps climbing to 3.

PasturesNew

My combi boiler had to be "topped up" with water - and the little plastic switch I used to do this broke away, meaning I had to use pliers... and if I didn't turn it exactly to the off position, water would still trickle into the system - causing it to overfill.

It was tricky getting it right, so what I would do is wait until I was going to be around for many hours, then do the topping up. Then for the next 4 hours I'd pop back and check it wasn't sneaking upwards. If it was, then I'd just tweak the screw back a bit more.

So, it could be that: water is still managing to trickle into the system from the switch/point where you do the topping up.

A plumber did tell me to not worry about it, and the water would simply fall out of the overflow. And if I just had another go at ensuring the switch was "fully off" then used the system it would go down again. Which it did (although I am a worrier)

suzyq2909

That's really useful thank you. Will try that and see how I get on.

I know how you feel - I have the urge to go check every 15 mins.

Canucklehead

Hi

The system pressure should be ,as you say, about 1 bar when the system is cold. As said you should first check to see if the method of filling is turning off fully.If you have a filling loop with a flexi hose then disconect it after filling.
The pressure relief device should not be used as an overflow device it will lead to problems.
If you still have a problem then call your installer who will check the expansion vessel and the pressure relief valve.
A good sealed system will not need topping up for at least a year or more.
Just curious ... what boiler is it.?

Corgi Guy.

geri1965_2

Bumping this thread as my boiler just did a mini explosion and some filthy water came out. The pressure looks as if it's too high so I've turned it off and I am scared to put it on again. Do I need to call someone out? Help!

moike

You should have a flexible pipe that connects the mains feed to the boiler, there should be a valve at both ends of this pipe, in theory this pipe should be disconnected after the system is topped up and both valves have been turned off.
This would have the benefit that you would know for certain that no additional water is entering the system, and also gives the facility to lower the pressuer by opening the boiler side valve and releasing some water pressure into a bucket (via the short hose)
Regards

Canucklehead

geri1965 wrote: »

Bumping this thread as my boiler just did a mini explosion and some filthy water came out. The pressure looks as if it's too high so I've turned it off and I am scared to put it on again. Do I need to call someone out? Help!

See post above yours.

What boiler.? Has it been serviced at all?

Corgi Guy.

geri1965_2

It's a Britony combi (French, I think). It's serviced every year by British Gas. I've just woken up my OH and he says he just has to turn a switch, the engineer told him how to do it.

He's looked at it and reckons it's not that high - could the radiators need bleeding?

geri1965_2

Right, well - the radiators have been bled and the pressure keeps creeping up to 3 and above - should be between 1 and 2, I think.

Any suggestions?

moike

Where did anyone say to bleed the radiators? did you read the advice above?

geri1965_2

moike wrote: »

Where did anyone say to bleed the radiators? did you read the advice above?

Yes, but I didn't understand it. Are you saying I should not have bled the radiators? All we did is what the engineer told us to do - I don't want to go disconnecting things and topping things up, I've had this boiler for 11 years and never had to do that.