Replacing cold water tank with mains supply.

[mjsubrt]

Hi,

I live in a small flat which has a cold water storage tank and an immersion heater below it and I've been wondering if it is possible to remove the tank and just feed the immersion heater and cold water taps straight from the mains as this would free up alot of space in the airing cupboard?

I know that new homes don't have cold water tanks anymore so is it ok to do it in my flat?

Thanks in advance,

Martin

 

[MANDATE]

Hi Martin.
Your immersion heater is in a hot water cylinder and water expands when it gets hot and would burst the cylinder if it was totally sealed.
To overcome this problem you have a cold water storage tank placed at least a metre above the cylinder to ensure hot water runs from the taps with a reasonable pressure and a open ended pipe goes from the cylinder up to the water tank to return the expanded water.
So I'm afraid the answer is 'No' you cannot replace the water tank with a direct mains connection.
Some new homes still have water tanks and hotwater cylinders.
You are probabley thinking of the 'Combi Boiler' used in modern heating systems, where the problem of expanding water has been overcome by a different method. These boilers incorporate a 'expansion vessel' which I understand contains a diaphram which flexes sufficiently to cater for the expansion. With this system you use water direct from the mains and there is no water tank or cylinder and you cannot have an immersion heater.

 

[breezer]

i am not a plumber or heating engineer but i think the answer is NO.
The tank is there to supply pressure to force the water out of you hotwater cylinder

Your tank has a ball valve which stops water coming in when the tank is full, if you connected your cylinder direct to the mains there would be nothing to stop the water from coming in. Also you could get water from your cylinder siphon out back into the water supply.

Houses that have central heating and hot water with no cylinder have a "combi boiler" which heats the water on demand.

 

[AnonymousImport]

You could change your hot water cylinder and water storage tank for an unvented cylinder, which is mains fed. Cost you though.