Hot water cylinder into loft

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HI all,

Im going to rent my spare room and to make the airing cupboard into a wardrobe. This mean the hot water cyclinder needs to go in the loft.

The Cylinder is a integrated type(with a built in header tank), made of copper and its about 90cm high so not huge. Im going to prepare all the space so its a quick(ish) job for a plumber to connect up.

My biggest concern is the weight on the loft floor/ceiling joists. So I am planning to run two 4x2 beams across the entire width of the loft (3.4m), one above the top of a load bearing central wall. Essentially they will run either side of the loft hatch in the pics below. I was also going to use a beam hangar attached to the stone walls with bolts to hold them in place, so in reality the beam will be 1-2mm above the current joists/ceiling beams or whatever they are called.


Is this sufficient, or should I use bigger beams? The 4" is ideal because this will bring them level with the insulation board that is already down.

Anyone see any problems with what im planning to do? The tank is going where the space blanket is piled against the wall.
 
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How far is the drop from the cylinder to the lowest taps ?
It came up in the plumbing area a while ago that if your cylinder is high up, the long drop will result in air being drawn down the vent pipe. This will create noise, and will also make the taps surge and splash.

Basically, the long drop creates the ability for a large flow rate. This creates pressure drop in the pipework from the header tank to the cylinder. This only needs to be the difference in height between the water level in the header tank and the highest level of the outlet plumbing where it tees to go up to the vent pipe and down to the taps. In your case, you might have a foot or less of head there, so only need that much (about 1/30th of a bar) before you draw air into the pipework.

You cannot block the vent pipe - it's needed for safety. And if you did, the vacuum could just make the cylinder collapse (suck in under vacuum).

You may need to significantly increase the pipe size (to reduce the pressure drop) between header tank and cylinder to avoid the problem.
 
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erm there is no header tank, its an integrated cylinder its got the cold water store built in. Will that still cause a problem? The tank is only moving 1.5m higher than it is now.

pictures are decieving, there's tons of headroom in the loft.
 
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That integral bit on top of the cylinder is the header tank - and it probably means you only have about a foot (or less) of head between the cold water level and hot water take off.
You may be better asking over in the plumbing forum for advice on whether it will be a problem or not (it's not something I've first hand experience with). Given "tons of headroom" you may be advised to use a separate header tank so you can elevate it a bit more.
 
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