Can anyone help with a central heating problem?

[Shinsei Jutsu]

For a while now our upstairs radiator has only been getting half warm, so last night I beld the thing. Loads of air came out and the radiator was nice and hot.
The heating went off as normal but now when the heating comes on that radiator stays cold. :cry:
I have checked the pressure in the boiler and all seems fine there, and all other radiators are hot.

Anyone have any idea what would be wrong and what I would need to check?

Thank you in advance

Shin

[Stingo]

Sounds a bit like it needs venting again - air will always find the highest point, there could be lots in the system. When I've bled mine, I find that I need to add more water to the boiler circuit to repressurise the system - the tap (a small shut-off valve or ****) for this in my case is located next to the boiler. The pressure gauge has a red zone and a blue zone - basically I need to keep the pressure in the blue zone.
It might be that air is being drawn into your system from somewhere so as fast as your bleeding it, the stuff is getting back in there...it'll be a case of narrowing down the possibilities...just my opinion, not a solution...there's lots of different boilers/systems out there.

[Mr Toad]

Try venting it again
It will depend on what system you have, but venting a lot of air from a radiator can require the system to be topped up by quite an amount. You may have induced an airlock (depends on how your pipes run)

Also consider what has caused the air to build up - it may be that your system is old and possibly subject to some corrosion which can cause a build up of gas - I'd make sure that you have corrosion proofer in the system, add some if you haven't.
The old trick used to be to drain off a jam jar full of water, put a nail in it, and if the nail started to rust in a day or 2, you need to add corrosion proofer. You can pick it up at B&Q

hth

[Viney]

Mines doing that. Pressure keeps dropping. I just keep bleeding the system and toping the wqater up in it.

[Shinsei Jutsu]

I topped the pressure up this morning, and the radiator is full of water, but it's not heating up. Could this be a air bubble or something in the pipe before that rad?
How do I get rid of it? Bloody things!

[keithd]

is the rad giving you grief the furthest away from the boiler? i had the same problems, it was just a case of persevearance, kept bleeding the bleeder and it seemed to cure it eventually, i'm guessing i managed to push all the air out of the system

[fizzwheel]

Warning shamless plug alert

Shin join the screwfix plumbers talk forum, post your question up on there and somebody will be able to help you

http://www.screwfix.com/talk/forum.jspa?forumID=25

[Shinsei Jutsu]

It's the only upstairs radiator. I will just have to persist and keep bleeding it.

Thanks guys.

[Viney]

It's the only upstairs radiator. I will just have to persist and keep bleeding it.

Thanks guys.

Or buy a jumper

[Shinsei Jutsu]

Well that screwfix direct lot! None of them have replied, unlike you lot who are on the case in seconds and so very very helpful. :wink:

thanks though Fizz, I'm sure they'll come through when they get up and get round to looking :wink:

[Mr Toad]

It's the only upstairs radiator.


As it's the topmost radiator, it's the one most likely to fill up with air - as air rises
You need to remove the bleed valve, and then keep adding water to your system (you'll probably need assistance from someone else at this stage) to push through any airlock or bubbles - you'll hear them coming out from the pipes into the radiator as a series of gurgles. You'll obviously need something to catch the water in - it's going to get a bit messy I'm afraid. Stick some old towels on the floor under the bleed valve, and try & catch the bulk of the water in a cup/mug/bowl/bucket whatever

My system is pressurised, so I add water from the mains via a filling loop which is quite easy.

[Shinsei Jutsu]

Thanks Toady!

I've been told that if it's an air block then shutting off all the other rads and just having the problem one on should force the air out too. I will give that a go as it sounds less messy, but I will get ready to bleed away if necessary.

[tigersaw]

I've got a similar rougue radiator, its furthest away from the boiler and looks like its been added after the initial installation. You can bleed it whilst the pumps running, but it gets cold and empty again the following day. Nothing seems to really solve the problem, I put it down to design / installation problems and have give up on it - its the guest room anyway :lol:

[Mr Toad]

I'm a bit of an expert on topping up/bleeding central heating systems - I'm very sad :lol:

My system has a leak somewhere, so it needs topping up every 2-3 days, or the pressure drops too low & the boiler starts to sound more like a kettle than a boiler :cry:

I'm fairly sure the leak is under the ground floor as there are no damp patches anywhere else in the house, so in the summer I'm going to have to start lifting carpets & floorboards to find the problem. I have an old house with suspended wooden floors, and when we moved in I laid sheets of hardboard over all the ground floor to stop the draughts before we had it carpeted. These hardboard sheets were fixed with a staple gun :roll:

It's going to be a swine of a job :evil:

What I really need is something like a tame rat, with a wireless webcam on its back, to have a good look around first :idea:

[sharriso74]

Can lend you one of my rabbits if you like. While I was rewiring my house one of the little b*ggers got under the floorboard and decided that no amount of coaxing was going to encourage him to come out. So ended up lifting nearly every floorboard in my living room.

[Mr Toad]

Can lend you one of my rabbits if you like.


Can you steer it :?:

If we tied a bit of string to a leg we could retreive it after a while :lol:

[kwak zzr]

I'm a bit of an expert on topping up/bleeding central heating systems - I'm very sad :lol:

My system has a leak somewhere, so it needs topping up every 2-3 days, or the pressure drops too low & the boiler starts to sound more like a kettle than a boiler :cry:

I'm fairly sure the leak is under the ground floor as there are no damp patches anywhere else in the house, so in the summer I'm going to have to start lifting carpets & floorboards to find the problem. I have an old house with suspended wooden floors, and when we moved in I laid sheets of hardboard over all the ground floor to stop the draughts before we had it carpeted. These hardboard sheets were fixed with a staple gun :roll:

It's going to be a swine of a job :evil:

What I really need is something like a tame rat, with a wireless webcam on its
back, to have a good look around first :idea:

thats some leak mr toad if you have to top up every 2-3 days, i have a simaliar leak on my hallway rad just a drip everynow and again and my boiler needs topping up to about 1.5psi every 6 weeks, i was told by a plumber that every 1psi your boiler drops is about 1 egg cup full of your system water, then the water that leaks out is replaced with air hence you having to bleed your end rad alot.
most small leaks stop when the heating is running because the joints expand its only when your system is cold that it will leak the most.

[Viney]

you could also have a faulty pressure valve in the boiler, which is what ours is. Sadly the council wont come and fix it as the boilers they put in 5-6 years agao, arent covered anymore, so they will have to replace the said boiler, and theres no budget for that!!

[22]

dont have the pump running/heating on while bleeding the rads, that only sucks more air into the system.

[kwak zzr]

and throws more water at you!