Help!!.. problem with Central Heating

urban_i

I hope someone can help...

As soon as I put my heating on at home within about 20 seconds I hear very strange sounds from under my sink in the kitchen (where the boiler is). It can only be decribed as a "loud banging" noise (or like something is reseting itself).

I then start to hear it in the pipes but the sound in the pipes are more like pressure builting up. It gets so bad that it sounds like something is about to explode, at which point i have to turn the heating off.

I have tried to take the air out the raditators ..but that hasnt helped.

Does anyone know what could be wrong and if I can go about fixing it without having to call out a expensive plumber.

Thanks

robnye

are you able to check your small overflow tank in the loft.....

i have two tanks, one large, full of cold water, the other is small and is the tank overflow, so can appear to be a little dirty (the water is used through the heating system ie radiators), whereas the cold tank supplys the emmersion tank.

if this tank is empty, ie ballcock valve has got stuck, then the banging noise can occurr

air in the pipes is the most obvious cause.

my tank also has a release/blead valve next too it, try opening/closing that (if you have one).

dark_star_3

A common problem at this time of year is pumps packing in. They sit idle (depending on the type of system) all summer and seize up.
This sounds like it could be your problem, (water not circulating, leading to overheating at the boiler...nasty banging noise)
First...low tech solution...locate pump and with the heating on...give it a thump (not too hard...but hard enough to give it a jump start)
if that fails. There should be a a round bleeding point slightly smaller than a 10p piece. With the heating off, unscrew it, some water will come out, but not much, insert a long thin screwdriver into the hole, this will enable you to turn the impeller manually and free it.
If these two options fail, you'll need a new pump.

To prevent this happening again, it's a good idea for people who have this type of system to run their heating for a few minutes a week over the summer.

aliasojo

Is this a new system (or new to you at least)?

I had a banging noise (sounded like someone knocking) which was a result of the flow being the wrong way in one of the radiators. Luckily I had the kind of valve that was easy to reverse so it was not a problem. Older valves may need to be removed which is a pain.

Of course if you've had the heating for ages and not had this problem before then I don't suppose that's the cause.

plumb1_2

1-No water in the system,check tank
2-Faulty pump,Renew

urban_i

how much does a new pump cost?

urban_i

also where do i normally find this pump? (as you can tell
plumbing not one of my strong points :-[)

plumb1_2

Pump cost £35-£65

http://www.plumbworld.co.uk/images/pwhv0003s.jpg

http://www.plumbworld.co.uk/images/pwhv0001s.jpg

you might find it in your airing cubboard,under floor,next to bioler,various places

RedOnRed

I've had two boilers that have both been noisey and made knocking noises, including the present one. I've always found in my case it's due to a particular radiator always needing bleeding.

You could also try a product that Fernox make call Boiler Noise Silencer...

http://www.fernox.com/?cccpage=boiler_noise_fixer_500ml&sub=9

Worked quite well for me in addition to bleeding the radiators.

Ivor_Headache

Urban-I Hi,

It is probably air in the system and bleeding the radiators doesn't always clear it.

You find that if you do get air trapped in the system it will always find it's way to the highest point. Therefore if you get into your roof space, look at the pipework, and try to ascertain where it is at it's highest. If you are lucky you may have a compression joint nearby. Slowly and gently loosen the compression joint, with a tray or anything underneath to catch water. Let some water escape from the system, hopefully you should gat a 'splutter' of air, the same as you do when bleeding the system on a radiator.

With a bit more luck, this might cure it.

urban_i

I finally built up the courage to wack the pump with a hammer (all be it the handle part of it)...and i couuld not believe my luck when all the banging stopped (almost instantly) ...
And you guys were 100% correct it was the pump that was not working as I heard it kick into action.

So a big thank to dark_star and the rest of the gang.