A basic central heating question.

[Deleted member 1258]

Not sure who your question was directed to??
I fill it till the needle stops.... which is on the green, about 3.
Incidentally it has, strangely, been working fine since. Maybe (hopefully) it was just a blip.
It will still need topping up every 3-4 weeks which, after reading other posts, I can live with.
With the old boiler I don't remember it ever having such a problem.

I think 3 is too high, our old one was topped up to 1.5 then topped back up when it was down to 1, we've had a new boiler recently and haven't had to top it up yet.

 

[MrGrumpy]

My last house had a combi , used to lose pressure as well. Maybe 2/3 times a year, I was pretty sure there was a leak of a radiator. Very very small. Bit of a pain, to be honest but other than that not an once of bother !! If losing it every few weeks then you have an issue. Check all rads for small leaks as well.

 

[Lookrider]

Did you do the " go to fix" of bleeding all the radiators
Surprising how this minor issue can play havoc ....but is an easy fix

 

[mistyoptic]

I think 3 is too high, our old one was topped up to 1.5 then topped back up when it was down to 1, we've had a new boiler recently and haven't had to top it up yet.

This is the advice we were given by the engineer too

 

[ColinJ]

I fill it till the needle stops.... which is on the green, about 3.
Incidentally it has, strangely, been working fine since. Maybe (hopefully) it was just a blip.

Too high - that's usually the pressure at which the boiler has to start venting excess pressure through the pressure release valve!

And don't forget - the pressure usually goes up by about 0.5 bar when the heating is on.

I think 3 is too high, our old one was topped up to 1.5 then topped back up when it was down to 1

I do mine to 1.5 and if I need to bleed the radiators it then drops a little. It goes up to around 2.0 when the boiler is in use.

 

[newts]

Not sure who your question was directed to??
I fill it till the needle stops.... which is on the green, about 3.
Incidentally it has, strangely, been working fine since. Maybe (hopefully) it was just a blip.
It will still need topping up every 3-4 weeks which, after reading other posts, I can live with.
With the old boiler I don't remember it ever having such a problem.

3 bar is too high for topping up, when the boiler heats up the pressure rises even further & the pressure relief valve opens.
Topping up the heating circuit is normally done when the system is cold, 1-1.5 bar (dependant on boilers user instructions).
when the system heats up it'll be around 3 bar.

 

[slowmotion]

Pinhole leaks are often the cause of lost pressure. Most people installed combis in systems that originally had conventional boilers. With a conventional system, any water lost by tiny leaks goes un-noticed because the feed and expansion tank replaces it. When the system is a pressurised one, those tiny un-noticed leaks are enough to cause a loss in pressure.

 

[MrGrumpy]

Yep , was our issue. Microbore pipes to rads . Hopeless !!