help needed with hot water tank overflow

[pauljones]

first my radiators came on when i switched hot water on.
Then the hot water tank keeps overflowing.
both hot and cold tanks seem connected somehow and the scum from the hot tank is now in the cold tank.
I replaced both ball valves as the cold one kept dripping and the hot one seized up.
Then i got ill and while away my mrs called a so called plumber in who ripped her off and now the pipes bang ,the overflow wont stop and there is no water supply to the hot water tank yet it still fills up and overflows, no hot water,only radiators come on still when hot water switched on.
Please can someone give me some advice???
And what would stop the ball valve to the small hot water tank from working? As it worked okay when i replaced it but not after the so called plumber had been?

 

[mickie]

3 way valve jammed and maybe coil split

 

[pauljones]

thanks mickie,
im quite competant with most things but could you please excuse my ignorance and elaborate; where is the 3 way valve located and coil?
is this a job that only an expert should attempt or is it relatively straight forward?
Also could this job be done fairly cheaply or is it going to cost a lot?

 

[darrenangel]

first thing we need to establish is the system you have. After your pump do you have one valve( with 3 pipes from it) or 2 seperate valves (2 pipes from each)

 

[pauljones]

after the pump it splits into 3 pipes below it but it joins another pipe 6 inches above.
The first seperation is approx. 18 inches below the pump and goes to a white box that says central heating one way and hot water the other way - is this the 3 way valve?, then about 12 inches lower it seperates into 2 pipes that go down beneath the floorboards.
The white box has an inlet from the pump, an outlet (i presume) which goes to the imersion tank and the 3rd goes to the hot water and below the floorboards .
the box has a sliding switch that says auto one side and manual the other and is connected to the electric.So this is obviously the selector for either hot water or central heating.
Also from the floor another pipe comes up and joins the pipe about 6 inches above the pump and runs parralel with the pipe leading to the pump
I hope that im clear enough

 

[kay-jay]

the unit with the sliding lever is the 3way valve. try sliding the switch manualy to see if it is jammed. if it moves freely, get someone to turn on heating demand while you observe what happens. repeat with hot water demand then report back....

KJ

 

[pauljones]

thanks kay-jay, i did what you proposed and when we tried to turn on the c.heating the pump kicked in and the valve made some noise and when i tried to move the slider it initialy worked as it should but then went loose as if it wasnt connected to anything (instead of ticking away and moving slowly back to the auto position like it used to do).
Then when we tried to switch the heatng off and hot water on it whirred and then when i moved the slider it moved as though it were connected it moved as it should, ticked away and then moved back to the auto position affter a minute or so but the radiators got hot (as well as the pipe for hot water).
The hot water tank upstairs in the loft still has no water in it now before i was ill i replaced both ball valves and both hot and cold were working correctly,
after the plumber came the hot water tank has no water supply but still filled up and has cross contaminated the cold water tank too,

 

[kay-jay]

could the plumber have isolated the supply to the ball valve and forgot to re-establish supply after tinkering??

have you tried pushing the ball valves down? this should force water to pass through and prove whether they are functioning. if they are not check for closed isolation valves or remove the ball valve to see if water passes through the pipe as it could be some kind of obstruction. if you can figure this out the hot water and heating issue may resolve itself or may need a new 3way valve.

 

[pauljones]

i replaced the old ball valves in both tanks and they were both working fine until the guy came to 'fix' the overflow problem. I have tried what you suggested and there is no supply to the hot water ball valve at all! ive looked at the possible places to turn off the supply but found none that were the culprit.
the only thing i havent tried are the valve/taps that have no way of turning them off (without using a tap/key) ,
I havent explained that very well but i mean the taps that have to have additional device to open or close the valve, they are the only ones i havent looked at yet

 

[kay-jay]

have you looked for one of these
http://www.****************/shop/Plumbing/Valves/Isolating+Valve+CP+15mm/d20/sd2696/p36879

fitted on the pipework just before the ball valve maybe?

or one of these
http://www.****************/shop/Plumbing/Valves/Gate+Valve+15mm/d20/sd2696/p83818

in the airing cupboard. if you have one that is on the cold feed pipe up to the cistern in the loft check it is open.


(replace the stars with toolstation .com)

 

[pauljones]

thanks kay-jay i'll check it out and report back. Ive tried the hot and cold taps/valves in the airing cupboard just above the immersion tank and both are fully open, i will have to go in the loft in the morning cos the kids are in bed now but i'll let you know soon as ive had a look
thanks for the help its very much appreciated. And the pics helped me also!! your a good man, cheers.

 

[pauljones]

both are open, found nothing else but the 3 way valve lets hot water to both outlets when hot water switched on.
The cold tank is still slowly emptying and filling constantly but the hot tank still has no direct supply but is still full and overflowing!
someone suggested raising it a little higher as a temporary fix, but if there is reflux from the cold tank then i suppose that would do no good, what do you think?
The brown scum that accumulates in the hot tank has recently been observed in the cold tank ,(to me it seems that there is reflux both ways) so does this indicate a split coil or just a problem with the 3 way valve or both?
Thanks to all who have helped me so far but i still nead more help please,

 

[kay-jay]

firstly when you say 'brown scum in the hot tank' this suggests to me the feed and expansion tank for your central heating system. the fact that this is now visible in the cold water storage system is not good and needs urgent attention as the f and e tank will likely contain chemicals from heating system cleanser and inhibitors. this situation becomes more urgent if as well as the hot water cylinder this tank also feeds all cold outlets other than the kitchen sink....think brushing teeth !!!

the issue sounds like it could be a split coil but equally could still be an issue with 3way valve jamming.

without being there the best i can advise is to change the 3 way valve as it is much much cheaper than changing the cylinder. if the new valve does not rectify the issue then unfortunately you may well be looking at a cylinder change anyway....

ask friends and neighbours to see if they can reccomend a good local plumber to pop round and take a look for you to confirm.

also you could post your location and perhaps someone on here may be able to help

 

[SafeGasInstall]

but dont go to yellow pages again I think you can do all this by your self ! You seem to be into DIY staff ! If you call a plumber will be costing you lot more then £65 which you were charged

 

[pauljones]

right thanks guys, im very grateful for your help,im quite competant at most diy things so im off to buy a new 3 way and tackle that first then see what happens,
once the valve is replaced whats the proceedure for cleaning out both tanks in the loft, (big one cold water ,little one hot water, to make sure that the water is safe as it has definate cross contamination, or is it only the cold water tank that needs cleaning?


i live in Halifax, West Yorks and if theres anyone in my area who would like to contact me then please do as i may have some work for you, Thanks

i'll report back later and let u know how i get on

 

[kay-jay]

good luck paul!

you will not need to clean the f and e tank as it is designed for central heating system water to expand into as the water in rads heats up.then feed it back in as it cools.

as for cleaning the other just google for a suitable product as i'm not sure of one off hand. follow instructions as directed on the packaging. basically just draining and re-filling and adding the stuff at the appropriate time.