Combi Boiler, But Still Using Tank

[Spreadmann]

Hiya Guys, love the forum, been a long time lurker and search facility user, but couldn't find anything on my situation. I am in the process of having a new kitchen and bathroom installed, and as part of the job I have dropped the kitchen ceiling which has exposed all the plumbing. (Bathroom is above the kitchen) I have a Vaillant Combi boiler, and all is pretty much plumbed as I would expect to find it, except for the cold supply to the bath which is fed in 22mm copper from a header tank in the loft. There is evidence of an earlier system in the airing cupboard, ie redundant cut pipes which I assume would have serviced a hot water storage tank, since removed, and the bath cold is the only thing not connected to mains pressure.

My question is would there be any reason not to connect the bath cold feed directly to the mains and do away with the header tank? And would there be any reason to have the arrangement I have, other than convenience of installation?

 

[Agile]

Usually lazyness.

But if the flow rate on your cold mains is low it might have been an intentional act.

If you mix cold with hot at the bath then you need balanced pressures.

Getting rid of a loft tank is very sensible! But see if it also feeds some WCs first!

Tony

 

[hansthebear]

lead or other dodgy pipework, old taps etc

 

[dcawkwell]

Check how much cold mains flow you have. 20 litres and you can
simply remove the cold header tank.

 

[Spreadmann]

But see if it also feeds some WCs first!
Tony

Definitely no cisterns fed by the tank - there's only one lavatory in the house and it's mains fed.

lead or other dodgy pipework, old taps etc

Only dodgy pipework is a lead waste through the wall for the bath which empties into a rainwater hopper - and will continue to do so for now, although I'll replace with plastic. I may replace the cast stack for plastic one day, but it's not an option right now.

Check how much cold mains flow you have. 20 litres and you can
simply remove the cold header tank.

Presumably you mean 20 litres per minute? And measuring immediately after the rising main stopcock will be ok?

Thanks to everyone for your input, it's much appreciated!

 

[dcawkwell]

Yes 20 litres a minute. If you have that at an outside tap or a good kitchen tap. 20 litres a minute or somewhere close is fine.

 

[Spreadmann]

Ok, nice one, I'll measure it tomorrow, thanks dcawkwell.

 

[Spreadmann]

Blimey, 20 litres per minute, I wish! I've got 7.5 litres only! Checked several times. So, I've investigated the tap at the street, (it's actually just inside my boundary) to see if that can be opened up further at all, but it can't. And it seems I've got lead pipework on my side of the tap even though it is 15mm copper which emerges from under the kitchen floor. I am assuming this should all be replaced with plastic? Which will of course mean digging a trench in my tarmac drive. Luckily the tap is only a foot underground, so presumably the pipe will be similar. Any thoughts?

 

[Hugh Jaleak]

Service pipe needs to be 750mm deep to protect from frost. It is possible to dig a pit either end and 'mole' to get a new service through, rather than trench through the drive, but that depends on your budget.

 

[dcawkwell]

Blimey, 20 litres per minute, I wish! I've got 7.5 litres only! Checked several times. So, I've investigated the tap at the street, (it's actually just inside my boundary) to see if that can be opened up further at all, but it can't. And it seems I've got lead pipework on my side of the tap even though it is 15mm copper which emerges from under the kitchen floor. I am assuming this should all be replaced with plastic? Which will of course mean digging a trench in my tarmac drive. Luckily the tap is only a foot underground, so presumably the pipe will be similar. Any thoughts?

If you live in london flows like this are typical in certain places.
Hence the reason you still have a cold header tank.

 

[Spreadmann]

I'm not in London, I'm in the Isle of Man. I've got another property around the corner from this one at which I've measured 20.5 litres per minute so I'm going to replace the service pipe. The water authority will replace their side, which is also still lead, free of charge at the same time. It seems a friend of a friend has moleing equipment so I'll see what he says. These jobs are often chain reactions aren't they! Be happy to get rid of the lead though.