Explanation

[hammers4spanner]

Last Thursday i got a phone call from a customer saying water coming down through the ceiling in the loft told me they had a tank up their.
Turned up and yes water overflowing out the top quick check and ball valve was kaput , put new one in and tested all good.

Today got a call same job water again pouring through the ceiling, went out ball valve not shutting off so rip out put another in .Fill up stay around for a while no issue ball valve all settled all good just about to leave and it does it again so this time shut off service valve drain tank .

4 o clock today same place tank is full of water and service valve off!!!!!

So thats two ball valves passing and service valve shut off and tank mysteriously fills wtf!!!!

Anyone got an explanation??

 

[Destroyer2813]

What tank cwst?

 

[hammers4spanner]

yes cwst

 

[jonnyswamp]

Cold mains back filling through hot ( mixer valve somewhere?) split coil in cyl (if system)

 

[hammers4spanner]

Ahhh never thought of the mixer issue back filling . Capped tank and fully drained it back tomorrow.

 

[chris watkins]

Kitchen mixer tap, just think of all the places the mains could be back or cross feeding the CWDS or C/F, could try isolating each to narrow it down.

 

[Phil]

So...on your second visit water was still coming through ceiling?

 

[hammers4spanner]

Kitchen mixer tap, just think of all the places the mains could be back or cross feeding the CWDS or C/F, could try isolating each to narrow it down.

The tank only feeds one tap and shower in the whole house so was thinking just taking the mains supply to tank and bypassing the tank and just pinging it to the feed out the tank .

 

[mfgs]

Why isn't there an overflow on the tank? Surely after water coming out the top of the tank and through the ceiling that would have been top of my list of suggested works.

 

[hammers4spanner]

Its blocked

 

[hammers4spanner]

Its also a loft rammed of stuff got zip all chance or running a new overflow unless you spend 2 days loft clearing

 

[REDSAW]

had one like that 3 plumbers later--£550 less in pocket he called me.
kitchen tan pushing up into cwst. so i charged him £400 and a new tap later job done

 

[hammers4spanner]

had one like that 3 plumbers later--£550 less in pocket he called me.
kitchen tan pushing up into cwst. so i charged him £400 and a new tap later job done

How quick it take you to work it out??

 

[chris watkins]

had one like that 3 plumbers later--£550 less in pocket he called me.
kitchen tap pushing up into cwst. so i charged him £400 and a new tap later job done

Know the value of your knowledge & skills !!!

 

[Best]

Piece of cake to diagnose water passing through a tap or other valve.
First thing I try to do is check the old ball valve is actually passing water when arm tight up.
If not sure then a torch shone down inside the cwt to see if water passing up the feed that goes to hot cylinder. If heat is in the hot cylinder water then a hazed water is evident going up through the cold water of cwt.
Then just a matter of checking taps - monobloc mixer at sink etc I would check first.
If you disconnect the hot pipe you will see cold water flowing from tap if fault is in that tap

 

[REDSAW]

Piece of cake to diagnose water passing through a tap or other valve.
First thing I try to do is check the old ball valve is actually passing water when arm tight up.
If not sure then a torch shone down inside the cwt to see if water passing up the feed that goes to hot cylinder. If heat is in the hot cylinder water then a hazed water is evident going up through the cold water of cwt.
Then just a matter of checking taps - monobloc mixer at sink etc I would check first.
If you disconnect the hot pipe you will see cold water flowing from tap if fault is in that tap

exactly this way 20mins.
i find shinng a stong torch to bottom of tank highlights theral disturbane.

 

[hammers4spanner]

Nope no cylinder in the building and put my hand on supply down to bathroom from cwst and stone cold . No way i could see in the tank either to risky probably end up wrecking something .

Only supplies two things one is a mixer tap so main suspect.

Either way binning the tank tomorrow

 

[REDSAW]

How quick it take you to work it out??

20 mins

 

[REDSAW]

had one like that 3 plumbers later--£550 less in pocket he called me.
kitchen tan pushing up into cwst. so i charged him £400 and a new tap later job done

forgot to add to this, that included my engineer report to the actual problem as he was pursuing a claim back for his money from 'reactafast' or whatever its called now!
as they installed a new cylinder saying the coil had pinholed