Where's my hot water going?

[gazbiker]

Guys, this is driving me bonkers!

I have a reletively new oil fired water and central heating system. The boiler heats water and it is stored in the immersion tank to be used as required.

When the system is "working" the boiler runs as usual i.e fires up, has a little rest, fires up etc and within 15 mins you get a full tank of hot water. This remains hot for quite some time i.e if the wife put's on the water heater at 6am I can still have a very hot shower at 9am afetr the system has turned off (we put it on for about 1 hour).

We went on holiday and when we come back the system stills "works" i.e the boiler fires up the tank fills with hot water and after one hour the boiler shut's down but if I go for my shower 3 hours later the water is luke warm not as hot as described above.

I checked that the three way valve is working and it seems ok.

So either the hot water is going somewhere? or the immersion tank has cold water coming in and diluting the hot water?.

I had this problem once before and it seemed to clear itself when I drained the system down and re-filled again when I had a leak outside.

It's really getting on my nerves! I had a couple of plumbers in to quote for my new bathroom and when I mentioned it they scratched their heads and didn't come up with any answers.

Anyone come across this? I need help before I consider ripping the whole lot out and putting in a new system!

Cheers

Gaz

 

[petit_pablo]

Do you have an overflow dripping at all? Particularly in the morning? Possible that either the coil has holed in the tank or a mixer tap is passing cold into the hot and diluting the hot water.

 

[gazbiker]

I have not noticed any overflow 's leaking water on the outside of the house.

We do have a mixer tap on the kitchen sink but it's relatively new and seems ok in operation.

Gaz

 

[Agile]

Plumbers fitting bathrooms may not be very experienced at heating.

They might well have thought that you only called them to give a free diagnosis of your heating problem.

I dont really understand from your description whats wrong so I cannot make any suggestions. Your system is very simple and there is not a lot to go wrong apart from the valve.

Tony

 

[adlplumbing]

is it pumped or gravity fed hot water cylinder

 

[namsag]

Take a simple one out the way first do you have any hot water pipes running under a concrete or suspended floor that may have a leak in it .
Tie ball valve up for a couple of hours dont use any hot taps and see if the level in tank drops

 

[foxhole]

Hot water tank vent may have dropped into header tank is not secured correctly causing hot water to siphon out into tank [overflow will run].

 

[gazbiker]

Plumbers fitting bathrooms may not be very experienced at heating.

They might well have thought that you only called them to give a free diagnosis of your heating problem.

I dont really understand from your description whats wrong so I cannot make any suggestions. Your system is very simple and there is not a lot to go wrong apart from the valve.

Tony

Hi Tony

The problem is that I'm losing the residual heat in the immersion tank even though we are not using the hot water.

In the past if we didn't use the hot water the water would stay very hot for hours, it's like the hot water is either disapearing somewhere or it is being cooled by cold water?

Any suggestions?

Cheers

Gary

 

[gazbiker]

Hot water tank vent may have dropped into header tank is not secured correctly causing hot water to siphon out into tank [overflow will run].

Hi Foxhole

I will check whether the overflow has dropped into the the tank tonight. There has been no water coming out of the external overflow?

Cheers

Gary

 

[gazbiker]

is it pumped or gravity fed hot water cylinder

Hi ADL

There is a pump for sure but I'm not sure whether that is to pump the hot water from the boiler or to fill the immersion tank.

I know that the shower is definately gravity fed.

Could this be an air block? how do I go about clearing air locks if there is one?

Cheers

Gary

 

[gazbiker]

Take a simple one out the way first do you have any hot water pipes running under a concrete or suspended floor that may have a leak in it .
Tie ball valve up for a couple of hours dont use any hot taps and see if the level in tank drops

I will try tieing up the ball cock at the weekend and see whether the level drops.
Cheers

Gaz

 

[dcawkwell]

A guess would be a mixer tap when off is allowing cold to feed back into
the hot tank.
If you have service valves on your mixer taps. Switch them off and monitor.

But this would if left long enough make the cold water tank overflow.

 

[gazbiker]

I went home at lunchtime and evn though the missus wasn't at home (so no one had used any water) the stop cock in the main loft tank was still running. Not gushing but a gentle trickle!

So it would suggest water is going some where but it is not coming out of the overflows?

I checked the meter out in teh road and the little clock was whizzing around even though no water was being apparantly used in the house?

Could this be part of the problem and how would it effect the water in the immersion heater?

I beginning to think I need to see a shrink!

Gaz

 

[dcawkwell]

Leaking pipe somewhere under the floor downstairs.
If your water meter is going around and you aren't using water
you have a leaking pipe in the house.
Turning the stop valve off as it comes into the house should stop the water meter turning to prove there is a leak in the house.

Dish washers? Washing machines check there too.

 

[gazbiker]

Leaking pipe somewhere under the floor downstairs.
If your water meter is going around and you aren't using water
you have a leaking pipe in the house.
Turning the stop valve off as it comes into the house should stop the water meter turning to prove there is a leak in the house.

Dish washers? Washing machines check there too.

I agree it looks like a leak but I do not have any damp patches on the floors or walls, this has been going on for some time surely I would notice a damp smell or something?

is there a commercial device for locating leaks? or do I need to get some one in with a divining rod?

Gaz