Cold-water and the hot water piping

[JOB6]

Hi everyone this question is related to the cold-water supply and the hot water piping.

The kitchen cold tap is connected to the cold-water mains which supplies the entire building/street with cold/clean drinking water. The hot water taps in the kitchen and bathroom are heated via the combi boiler which is connected to the mains cold supply thus heat up when the boiler is fired up. However, the cold water taps in the bathroom (bath and sink) are connected to the water storage tank in the buildings loft, the water tank supplies cold water to the bathrooms to all the flats within the building.

Now for the actual question: is it possible to have the hot water supply fed via the storage tank water in the loft rather than via the cold water main? If so how would this be done?

The flat I am in now didn’t have a boiler a few years ago, and indeed had its own small black water tank in the storage room which was used to supply hot water to the flat. When the boiler was installed the black water tank in the flat was cut off and the hot water was then hooked up to the cold-water supply. (The tank is still in the storage room empty and the stopcock is turned off but when turned it still works and fills the water tank up)

Any information would be appreciated thanks.

 

[Madrab]

The boiler would almost always be run from a mains supply, so no it wouldn't normally be supplied from a cold water cistern, this ensures pressure and supply is a constant. A cold cistern would be hard pushed to supply the boiler with the pressure and flow it needs.

 

[JOB6]

Thanks for that piece of info, just wondering what the purpose of the black water tank in the storage cupboard was used for? It was in use before the boiler was installed (4 years ago)

 

[Doggit]

If you've got taps being fed from a storage tank, I would get them plumbed in to the incoming mains supply so you are completely self contained, the pressures will be more even, an you'll cut out any risk of legionnaires disease.

Sorry, but why do you want the hot water to be fed from the tank.

The black water tank was very likely a water heater.

 

[slippyr4]

Was the black tank actually a feed and expansion tank? Was your old boiler a combi?

 

[JOB6]

Yeah that's right it is a old feed and water tank, and before the combi boiler was installed there was no combi boiler in the flat. There was a hot water cylinder in the storage room where the water tank is and a gas fire in the living room, then it was pulled out and central heating put in.
For some reason I get a rash from using the hot water from the combi but when I heated the cold water from the bathroom cold tap and used it to bathe I didn't come out in tiny little blisters or itch, so just wondering if everything is correct with temp, the pipes etc...or maybe there are chemicals which I may be sensitive to.

 

[Doggit]

I've never seen a problem with the hot water from a combi boiler before. Did they fit any water conditioners like a combimate water softener. And can I ask what temperature you're running the combi at, as there are some people that can't handle water that's too hot.