Magic Expansion tank

[Rabliv]

I have a similar problem to that of padster in earlier post, except that my expansion tank is overflowing (constant drip) and it is definately not the float valve. There is also nothing coming out of the expansion pipe above the tank. this leads me to believe I have a 'magic tank' which is producing its own water.
My central heating is off at the moment, but with the hot water on the radiator in the bathroom becomes very hot. Could I have some sort of short between my hot water and central heating or can anyone suggest anything else?

I took the water level down a bit and it has rose by about a bucketfull in about 3 hours.

 

[Bahco]

TIe up your larger tank float valve and do not use any hot water or anything else supplied by this tank and monitor the level.

If it empties by itself suspect your cylinder coil is split.

 

[ollski]

sounds like you have an indirect cylinder with a split coil.....bad news, new cylinder. Don't end there though it also sounds like your 3 port valve is passing, may as well fit a new one while you're drained down for the cylinder.

 

[Rabliv]

Thanks very much both of you, I will follow your advice whilst waiting for a less expensive diagnosis. You can only hope

 

[ChrisR]

Many a bathroom will get hot when the water comes on because, like mine, it's designed that way, to warm me and my towels. If the diverter valve was dud you'd get other rads hot too.

There, that's saved you a bit of money

 

[Rabliv]

Chris,

Music to my ears as a canny Scot. However, just finished testing Bahco's theory and sure enough the level in my main header tank went down.

Does anyone think it is a very bad idea to run some sealant liquid through the system whilst I save up for a new cylinder? (used it before with good result on my old boiler for a small leak on the waterbox cover, whilst I saved up for a new boiler)

 

[Bahco]

Does anyone think it is a very bad idea to run some sealant liquid through the system

I wouldn't fancy washing up in sealant filled hot water.

Get your wallet out pal

 

[ollski]

Does anyone think it is a very bad idea to run some sealant liquid through the system

I wouldn't fancy washing up in sealant filled hot water.

Not to mention inhibitor ,magnetite sludge, rust and more than likely legionella from a header tank...not my idea of a good bath.
The radiator in the bathroom may well be on the heating side, but I presumed you mentioned it as it is doing something it wasn't dong before ie heating up....if thats the case the diverter valve is passing. It may affect several rads or as in my case at home just the one (its in the office though and i just can't be bothered...its nearly the end of summer)

 

[Rabliv]

Does anyone think it is a very bad idea to run some sealant liquid through the system

I wouldn't fancy washing up in sealant filled hot water.

Not to mention inhibitor ,magnetite sludge, rust and more than likely legionella from a header tank...not my idea of a good bath.
The radiator in the bathroom may well be on the heating side, but I presumed you mentioned it as it is doing something it wasn't dong before ie heating up....if thats the case the diverter valve is passing. It may affect several rads or as in my case at home just the one (its in the office though and i just can't be bothered...its nearly the end of summer)

Can anyone suggest something to free rusty wallet hinges?