Loft tank question

[TheFew]

Hi,

I am trying to understand how my loft tank works and was looking for some advice...

So in my loft I have two closed/covered black water tanks, which are connected to each other by a 22mm pipe - so in essence they a single tank.

One tank has a 15mm cold feed controlled by a ball float valve providing new water.

One tank has two 22mm outflows.
- One of these seems to go to the bottom of the emersion heater to refill it.
- the other disappears down under the upstairs floor and I think it feeds the cold water supply to one of the upstairs bathrooms.

So far, so good I think.

What confused me however - is that the pipe work connected to the top of the immersion tank comes up into the loft and drops through a hole in the top of the loft cold water tank. So I assume that this is some form of pressure relief/vent from the hot water tank?

Would this be normal to have hot water potentially feeding into a loft cold water tank?

Thanks

 

[dlockers]

It's an F&E system, just Google it - nice YouTube videos. The big tank is a 'head of water' whilst the smaller one is for your heating.

 

[TheFew]

It's an F&E system, just Google it - nice YouTube videos. The big tank is a 'head of water' whilst the smaller one is for your heating.

Thanks. For clarity I have two large tanks in the loft which are the same size and connected.

There is a small header tank in the loft, but this is empty and capped off, so no longer in use.

 

[dlockers]

Thanks. For clarity I have two large tanks in the loft which are the same size and connected.

There is a small header tank in the loft, but this is empty and capped off, so no longer in use.

Edit: no idea. If you have no small tank not sure why you have 2 big ones

 

[TheFew]

The house has multiple bathrooms and two immersion tanks - used to be a bed and breakfast - so perhaps just two tanks to make a super big one!

 

[decto]

Likely to be as you say, just two joined tanks as there is a limit to how big a tank you can get up there.

The pipe that feeds into the top is the vent pipe, this allows the hot water to expand and in the case of a fail where the immersion heater stuck on would allow the steam from the boiling hot water tank to escape preventing an explosion.

 

[TheFew]

Likely to be as you say, just two joined tanks as there is a limit to how big a tank you can get up there.

The pipe that feeds into the top is the vent pipe, this allows the hot water to expand and in the case of a fail where the immersion heater stuck on would allow the steam from the boiling hot water tank to escape preventing an explosion.

Thanks.

I had assumed the mixing hot water into your cold tank may be a health issue, but I guess it is only used in an emergency event.

I've only looked at the tanks as they have started overflowing out into the garden. So I guess I have a leaky ball float value or a knackered washer.

From a quick look the valve seems to fill the tank at a very slow trickle and continues to drip with the ball fully raised up. So replacement it is.

Do people ever clean loft tanks out? They have a layer of deposits on the floor of the tank and a few bits floating on the surface.... but I guess are only really used for washing and teeth cleaning..

 

[decto]

Thanks.

I had assumed the mixing hot water into your cold tank may be a health issue, but I guess it is only used in an emergency event.

I've only looked at the tanks as they have started overflowing out into the garden. So I guess I have a leaky ball float value or a knackered washer.

From a quick look the valve seems to fill the tank at a very slow trickle and continues to drip with the ball fully raised up. So replacement it is.

Do people ever clean loft tanks out? They have a layer of deposits on the floor of the tank and a few bits floating on the surface.... but I guess are only really used for washing and teeth cleaning..

Mine is only used for hot water as I plumbed mains water to the cold taps.

Silt builds up after serval years, I changed the tank for a larger one 20 years ago when I added a shower pump. Water pressure here is not great so combi or electric shower are marginal.

Water in the tanks is chlorinated anyway, so should be ok. Not recommended to drink stored water but fine for washing, teeth etc.

 

[SpellowHouse]

The house has multiple bathrooms and two immersion tanks - used to be a bed and breakfast - so perhaps just two tanks to make a super big one!

Exactly. At some stage the second system has been added and rather than fit a new, larger water tank, they have added a second one and linked it to the first.

 

[Semple]

Thanks.

I had assumed the mixing hot water into your cold tank may be a health issue, but I guess it is only used in an emergency event.

I've only looked at the tanks as they have started overflowing out into the garden. So I guess I have a leaky ball float value or a knackered washer.

From a quick look the valve seems to fill the tank at a very slow trickle and continues to drip with the ball fully raised up. So replacement it is.

Do people ever clean loft tanks out? They have a layer of deposits on the floor of the tank and a few bits floating on the surface.... but I guess are only really used for washing and teeth cleaning..

I remember as a kid my parents telling me not to drink the water from the upstairs bathroom, did eventually learn it was because the taps were fed by the tank in the attic which as you've said isn't particularly hygienic.