Radiator problems...

[happyhopefulmummy]

Two of the radiators in my house are cold at the top and boiling hot at the bottom. I've bled them countless times, and no air is coming out (no liquid either). It is meaning that the rooms really aren't warming up. Does anyone have any idea what's wrong with them? Am I going to have to replace them? (Please noooo!!!)

you probably need more water in your system. look by your water cyclinder and you might have a small 'tap' type thing that you can move? on one of the pipes? if you move it the other way it will put more water in. you need someone at the boiler to shout when the dial's moved - so it doesn't go into danger area and get overfull. i think ours should be on 1.5-2.

cold at the top means air in them

nothing coming out when bled means no pressure

have you recently taken any rads off for decorating?

do you have a sealed system wih a pressure gauge on the boiler (I guess not) or one with a feed and expansion tank in the loft, probably older?

are these cold-topped radiators upstairs? have you got a hot water cylinder, and is it still hot?

Thanks for the replies. Yes, 2 of the 3 upstairs radiators are the problem ones. We haven't taken any of them off. I'm very nervous about doing anything electrical or water related in the house myself!

Our boiler has nothing on the face, I can't get the cover off either. Can't see a pressure gauge. Our water tank is in the loft. I'm guessing seeing as I can't see anything on the boiler I should mess with this myself.

If its something I can't do myself, will I have to call a plumber? How much are they likely to charge?

piglet knows more about this than me - i just know my system. if you don't have a round dial on the outside of your gas boiler it would suggest to me that you have a different sort of system to ours.

in our area plumbers vary quality wise big time, so i would suggest you go by recommendation

you don't have neighbours with same systems? ie live in newish houses with all same boilers etc as you could ask them?

I live on a typical London street in a 3 bed victorian terrace. I'm guessing all neighbours will be different depending on what the installed and when...

I think you have a feed and expansion tank in the loft. Its purpose is to keep the system topped up with water. It will be a plastic tank about 18x12x12 inches. Inside will be a float valve (ballcock) like in a WC cistern.

Climb up and see if there is water in this tank. If not the valve might be stuck. It could free up for a bit if you jiggle it but you should fit a new one. You will need a set of wrenches. Valves usually last 20 years or so and only cost a few pounds.

If the tank does have water in it, and more comes out of the valve when you press the float down, then most likely you have a sediment blockage in the feed and expansion pipe. This will require either some DIY plumbing or a pro. It is very common with old open vented systems that have not been looked after.

It does not need a gas engineer because it is just repairing copper water pipes and no need to touch the boiler.

Thankyou very much piglet - ill pop up and have a look. or my husband will as I am not allowed in loft since I fell through the ceiling

Whenever you are working on an F&E tank, it is worth baling out the mud from the bottom into a bucket, and sponging the inside of the tank clean with a drop of bleach. This will save adding more sediment to the system and reduce the risk of fungal growth in the tank. If it does not already have one, get a close-fitting lid to prevent wildlife drowning and rotting in the tank.

There are chemical cleaners I can tell you about once you have solved the absence of water problem.