Radiators not bleeding properly


Postby jamiebogle » Sat Nov 08, 2008 6:04 pm

I had a new central heating system installed a couple of years ago, and have occassionally had to bleed the odd radiator. However 3 radiators in the house don't bleed at all. When I turn the bleed valve there is no rushing off air coming out so the rads never get any better than luke warm.

Two of the rads are close to the boiler, one is downstairs.

Any help out there?
jamiebogle
Rank: Labourer
Progress to next rank:
50%
Posts: 3
Joined: Sat Nov 08, 2008 6:00 pm

Sponsor

Simply Build It

Postby Steve the gas » Sun Nov 09, 2008 4:29 am

Hi,

Only bleed rads with the system OFF.
Steve the gas
Rank: Site Agent
Progress to next rank:
56%
Posts: 780
Joined: Sun May 04, 2008 7:07 am

Postby jamiebogle » Fri Nov 28, 2008 2:35 pm

That still hasn't worked. It's almost as though there is no pressure forcing the air out of the affected rads.

The pressure bar on the combi is what it should be however.

Any more ideas?
jamiebogle
Rank: Labourer
Progress to next rank:
50%
Posts: 3
Joined: Sat Nov 08, 2008 6:00 pm

Postby htg engineer » Fri Nov 28, 2008 2:51 pm

As StG says, plus what kind of system is it ?

I'd imagine it will be pressurised with it only being a couple of years old. So what is the pressure gauge reading ?

htg
htg engineer
Rank: Project Manager
Posts: 3224
Joined: Tue May 22, 2007 5:22 pm

Postby jamiebogle » Fri Nov 28, 2008 3:37 pm

The boiler is a Worcester Greenstar 28i junior.

The pressure gauge reading is showing about 1 1/2 and the guide marker is 1, so there's slightly too much pressure in the system at the minute, but it always fluctuates anyway between 1 and 2 when the boiler is on, which I guess is to be expected.
jamiebogle
Rank: Labourer
Progress to next rank:
50%
Posts: 3
Joined: Sat Nov 08, 2008 6:00 pm

Postby htg engineer » Sat Nov 29, 2008 12:03 pm

1.5 bar pressure is fine, very odd for a pressurised system not to refill easily.

Did you try venting the rads with the CH turned off ?

The vent may be blocked, turn off both rad valves, remove vent nipple and insert a pin into the rad vent point.

(this is in relation to other posts - this is a common fault especially if leak sealer has been added at some point, that's why i'd only use leak sealer as a last resort. Also causes problems with auto airvents)


htg
htg engineer
Rank: Project Manager
Posts: 3224
Joined: Tue May 22, 2007 5:22 pm

Display posts from previous
Sort by
Order by



  • DIY How to Project Guides

  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!



 


  • Related Topics