Central heating question?

Question

Ive recently bought a house and the central heating was working fine. I had a new kitchen fitted and turned the water off the plumber. It was leaking so I opened all the hot taps to get rid of the water.

Since turning the water back on my central heating comes on and the radiators go luke warm, then the boiler goes off. It kicks back in sporadically but doesnt heat the radiators very well.

I've tried all the stuff in the manual and the boiler is fine. Ive also set my thermo to max but nothing. Ive now been advised to drain all my radiators (in case there is trapped air).

Will this correct the problem,and if not, can anybody diagnose the problem?

Answer 1

Sounds like trapped air there is a little hexagon nut at one end of the rads open it with a valve bleed key get one in any large D.I.Y. store and turn hex nut to the left, don't what ever you do completely unscrew this nut just loosen it until you see a little bead of water appear if you hear air hissing keep the valve open do this with all your rads starting with the downstairs ones.

Answer 2

If you empty your radiators you will fill them with air. You need to fill them with water and bleed the air out of them by means of a small valve that will be found on one end. Slowly open the valve in an anticlockwise direction with a special key, that is available at your local hardware shop and release the air when water starts to flow tighten the valve gently and do not over tighten. This should be done with the heating system switched OFF as doing with it on could draw more air into the system. You could also check to see it there is a bleed valve on the top of your immersion tank if so undo the knurled screw slightly and again remove the air.

Answer 3

Have you left it on long enough, the hot water cylinder will sometimes take priority for the heat from the boiler, if not that, the diverter valve is stuck, in the cylinder cupboard may be a silver or white box on the pipework, a little lever on the side may be stuck, try moving it, if there is resistance, move it a little then let it go back, if no resistance, turn the heating off and try again. While your in the cylinder cupboard. open the vent on the pipe going into middle of cylinder (if no vent don,t worry).

Answer 4

You can buy a special key used to bleed the radiators, or you can use a screwdriver. This lets out the air. If that doesn't work, you will need to call a plumber to diagnose the problem.

Answer 5

sam your radiators should have air bleed screw fittings set in one end .. what you can do is to use a special key that fits the raditor air bleed vents and go round each one letting out the trapped air.. There is another possible cause and thats trapped air in your boiler. there should be a air vent on your boiler also which may need to be bled aswell

Answer 6

the other answers seem right enough but possibly the pump might be faulty it should be in the airing cupboard if it was run dry you may need to prime it undo the large screw on the front while it's running you should be able to see the centre rotating very fast touch it with a screwdriver to check if the pump is not working it will not circulate the hot water around the radiators

Answer 7

you might have trapped air in the radiators, you need to bleed them. open the ends up with a special radiator key, do it slowly and you will hear the air escaping, and as soon as water starts to leak out, tighten it up quickly

Answer 8

That seems right........ there may also be dirt in the system. There is a product on the market(cant remember the name) that cleans it. Get the plumber in to balance the system properly

Answer 9

bleed radiators should be fine not drain

Answer 10

Surely instead of draining down just bleeding them might do it.