Try out your heating system now, don't leave it till it gets cold, then discover the pump or the diverter valve is jammed.

Happens every year, about 10 all ring up the same day, to be told I can't come for a week.

If the pump isn't sending water around the radiators, turn off the boiler immediately, if the impeller can be freed, it can carry on for longer, but if left powered up will burn out.

If you can see a chrome disc with a slot in it, on the head of the pump, undo, a dribble of water will follow but no more.

Then poke a slim bladed screwdriver into the hole, you should feel a slot on the impeller shaft, give it a twirl, then turn on the power, the pump should start to turn, then replace the disc.

Originally Posted by vinniethemanxcat

Try out your heating system now, don't leave it till it gets cold, then discover the pump or the diverter valve is jammed.

Happens every year, about 10 all ring up the same day, to be told I can't come for a week.

If the pump isn't sending water around the radiators, turn off the boiler immediately, if the impeller can be freed, it can carry on for longer, but if left powered up will burn out.

If you can see a chrome disc with a slot in it, on the head of the pump, undo, a dribble of water will follow but no more.

Then poke a slim bladed screwdriver into the hole, you should feel a slot on the impeller shaft, give it a twirl, then turn on the power, the pump should start to turn, then replace the disc.

Many thanks for that. While you're on, I can't seem to get a good picture on the telly? Is it because I've left food rotating in it overnight, or did I leave a fork in it by mistake.

I've taken out the clunge (and she was happy to be out of the house, to be honest) but I can't get a proper picture, for love, nor money.

Oooh! An expert! Let's have your views on this one.

Moved into the house about 25 years ago and soon discovered that the heating system (general term) made lots of loud banging noises - usually when the timer clicks on or when the thermostat kicks in. I drained the system, got rid of loads of sludge, refilled adding Fernox and all was well for a few weeks. Then the banging returned. So I drained the system, got rid of more sludge, refilled adding Fernox and anti-knock. Fine for a few more weeks, then the banging returned.

Resorted to British Gas, with whom I have a maintenance contract. "It's the boiler." New boiler, a few weeks, banging noises started again.

I've noticed that the hot water header tank collects limescale (as in, it's dumped out through the breather(?) pipe that returns into the tank). I'm guessing that there's a problem with the hot water side of the system as opposed to the heating side and so anti-knock isn't going to help. But what is the problem and how to resolve? (British Gas's standard answer is "Need a new boiler").

Cheap answers preferred, please.


PS. It's a very hard water area.

Originally Posted by putteesinmyhands

Oooh! An expert! Let's have your views on this one.

Moved into the house about 25 years ago and soon discovered that the heating system (general term) made lots of loud banging noises.

That will be the Austrian woman in the basement with a hammer, signalling that she wants to go home.

.-.. . - / -- . / --- ..- - / -.-- --- ..- / --- .-.. -.. / .--. . .-. ...- . .-. -

Just what we needed a expert for questioning. My heating system keeps losing pressure but we cant see why nothing obvious leaking and such. Lots of lovely hot water just low pressure any ideas?

Yours A_A

Originally Posted by King_of_the_Burpas

That will be the Austrian woman in the basement with a hammer, signalling that she wants to go home.

.-.. . - / -- . / --- ..- - / -.-- --- ..- / --- .-.. -.. / .--. . .-. ...- . .-. -

No, it doesn't sound like that. At first it made a noise like .-- .- - . .-. --..-- / .-- .- - . .-. but that wasn't related to the thermostat and anyway, it stopped after a few days.

Oh Shit! trust me to open my mouth.....


Puttees, are you saying that the pipe that comes up and over the header tank is pouring out water into the tank when the heating comes on?

That is called "pumping over" and is caused by the pipework being badly designed so that the pump is forcing water up the vent pipe and back into the system, carrying oxygen as it goes, a bit like the pump that oxygenates an aquarium...... deadly to a heating system, it rots the radiators, which is what the sludge is....a form of iron oxide which blocks the waterways in a boiler.

This is something which should be sorted first, it causes rads to rot through in a very short time.



AA.. I assume it's a combi that is losing pressure, is it fairly quick, like a day?

First thing to try is fill it to say 2 bar, then using the instructions, turn off the flow and return valves on the heating pipes just under the boiler, (make sure the boiler is turned off)

If the pressure drops, open up the 2 valves again, if the pressure rises, it's the pressure vessel, which is used to buffer the pressure rise when the heating comes on.

An external one can be fitted, but if the combi is old or a crap make it's best to replace the boiler.

Right back to the SA Chenin Blanc.

It's not a combi and the house is only 5 years old. It is a gledhill boiler mate if that is any use.

AA, like most one man bands, we pick out areas that we know we can make a living out of and turn down the rest.

There are a lot of builders, arcitects etc out there who fit shite and walk away, never to go back, specifying by coercion or bribery in the opinion of many of us.

Here is one you could try, it could be as simple as no top up water, also there are forums like DIYNOT that could help.

Gledhill BoilerMate thermal stores in detail

Thanks Vinnie. Seen as you did it virtually have a virtual tenner for your time.