Where does my overflow go?

[robbie77]

I have added a new cold water tank into the loft with a view to connect it to the hot water tank that I am moving in a cupboard.

I am bit confused with the overflow. The new 50 gallon tank say it should stick out in a conspicuous place from the roof but I can't see where it goes in my old system?

When ready I was going to move the smaller tank in the loft next to the new 50 gallon tank but I'm confused as to where the overflow should go as I am trying to copy existing tank setup in the loft. Is this the best idea?

I can see that the rising main fills both tanks from 15m pipe but where does the excess go? Back into circuit somewhere?

Any help as always much appreciated

 

[Burnerman]

Can't see any overflows there - just the usual fill pipes and expansion pipes.
Surely there are some?
John

 

[robbie77]

Surely there are some? icon_confused.gif

That's what I thought but I can't see one!

So If I copy the exisiting setup replacing the 25 gallon with a 50 gallon in the loft IF I add an overflow it should be ok?

Do I need an overflow on both tanks?

Thanks

 

[buck51]

it looks to me that there is an overflow connector in white behind where the vent and the feed crossover but cant make out if its connected

 

[Burnerman]

If you can stick your head into either of those tanks, the water inlet should be at the highest point, and any overflow should be just below this.
Certainly you can duplicate this system in your loft, make a nice strong frame to carry the weight.....and add an overflow! As far as I know, there's no problem using 1 overflow for both tanks, so long as one can't spill into the other.
John

 

[robbie77]

Thanks John,

So looking at my picture the big tank could have a pipe going into the little tank that then routed outside?

The small black tank is the "primary circuit" central heating top up tank type thing is that correct?

 

[AlanE]

If you a connecting two cold water storage tanks together but using single overflow it MUST go to the tank with the float valve. Float valve in each requires overflow to each.

 

[Burnerman]

If you a connecting two cold water storage tanks together but using single overflow it MUST go to the tank with the float valve. Float valve in each requires overflow to each.

Agreed - he's going to use two separate tanks, one header and one F/E I gather. Each will have its own fill valve, and no other connection other than the overflow.
John

 

[Burnerman]

Thanks John,

So looking at my picture the big tank could have a pipe going into the little tank that then routed outside?

The small black tank is the "primary circuit" central heating top up tank type thing is that correct?

Ideally, each tank should have its own overflow outlet, progressing downwards, where they can join and continue to the outside.
Your small black tank is the feed and expansion tank (F&E) that keeps your CH topped up. There should only be about 4" water in this one - but the other galvanised tank (didn't think there were many of those still around) should be full. This keeps your copper cylinder full of cold water, ready to be heated.
Your new tanks will have lids for them - much more wholesome but you'll have to cut a hole so the expansion pipes can poke through.
John