Bleeding a radiator troubleshooting

Dr.Winston O'Boogie

So I bled the radiator in my house last night, and everything went fine. I waited until the air had hissed itself out and then tightened the screw again.

However...now when I turn on my heating, it doesn't seem to come on at all in the entire house. All the radiators stay cold (most of them were already working, it was just the bedroom ones that needed bleeding). I left it on for an hour and there was no heat at all coming out of them.

Anyone any ideas on whats going on??

Hagar

I would bleed them all starting with the one nearest the boiler.

Bald? er, dash!

You've probably de-pressurised your system when you bled the rads. There is usually a pressure gauge near the boiler, which should be reading something between 1 - 2 bar (may be higher depending on your installation). If it is lower, your system will not work. There should be a valve (flat screw-driver head req'd) on the inlet to the system, which you can open to increase the pressure again.

Or... call a plumber!!!

Pete67

niallo24 wrote: »

So I bled the radiator in my house last night, and everything went fine. I waited until the air had hissed itself out and then tightened the screw again.

However...now when I turn on my heating, it doesn't seem to come on at all in the entire house. All the radiators stay cold (most of them were already working, it was just the bedroom ones that needed bleeding). I left it on for an hour and there was no heat at all coming out of them.

Anyone any ideas on whats going on??

Did you actually get water coming out of the bleed screw at the top of the radiator? You should have once all the air has been removed. If not then you were probably letting air in rather than out.

If it's a sealed system then you have to add water to maintain pressure as you are bleeding radiators. Otherwise you will end up drawing air in rather than removing it. You will also drop the pressure in the system to near zero, which may prevent the boiler from running, especially with gas boilers which have a low pressure cut out switch.

Is the boiler running and radiators not getting hot, or is the boiler failing to start up at all?

Dr.Winston O'Boogie

Pete67 wrote: »

Did you actually get water coming out of the bleed screw at the top of the radiator? You should have once all the air has been removed. If not then you were probably letting air in rather than out.

If it's a sealed system then you have to add water to maintain pressure as you are bleeding radiators. Otherwise you will end up drawing air in rather than removing it. You will also drop the pressure in the system to near zero, which may prevent the boiler from running, especially with gas boilers which have a low pressure cut out switch.

Is the boiler running and radiators not getting hot, or is the boiler failing to start up at all?

Yeah water came out, when it did I just tightened it back the other way. I read up on it before doing it, and basically it said that I should turn the heat on so there is hot water at the bottom of the radiator, then turn it off when I am bleeding them, which I did.

I think the boiler is failing to start, it makes a bit of noise initally and then goes quiet...

quietsailor

Some gas boilers have a viewing port you can see the flame through, if you have this watch to see if the flame is present.

If the boiler is outside on the pavement start it and CAREFULLY wave your hand over the exhaust, if its not hot then its not running
(I know all the professionals are going to jump on me saying thats not how the professionals do it - but I understand from the OP that poster is not a plumber),

If its an internal one and you can't get to the exhaust see if you can get to pipes close to the boiler. Start it and see if they get hot. If its working they should get hot immediately, if they get hot slowly then your pump is probably not working. If they don't get hot all the boiler is goosed :eek:

It seems unusual that the boiler breaks immediately after you bleed the system, more than likely the system pressure has dropped too much. Like another poster said look for a pressure guage and there should be a valve close by to add water to the system.

Hope thats some help

leinster93

First you need to locate the pressure gauge of the boiler and as pointed out it should be between 1-2 bars. In alot of cases now, to increase the pressure level there is a primary radiator which when bled will increase in pressure. A lot of the new houses have this system though I had to contact the builder to find out which bloody radiator. Anway, try bleed the radiator in the bathroom if there is one. Hope this helps.

Dr.Winston O'Boogie

Thanks for all the help guys, I am beginning to think it may be the pressure alright so I will check it when I get home and take it from there!