My house was built in 1902 and still has a gravity fed system with a cold storage tank in the loft. Nowadays we have quite a small plastic storage tank (50 Imperial gallons) but the old tank was much, much bigger than this. The original tank started to leak when I was a child about 40 years ago. It was galvanised steel and so big that it could not be taken out of the loft through the hatch. It was put in place before the roof was built and lasted over 70 years. It could probably have been patched actually and still be in use. I could calculate the capacity by measuring it but a guess it is 150 gallons at least.
Does anyone know why such big tanks were used? I am totally guessing but was it because the mains supply was unreliable or very poor in pressure? Might it also have been to try to get a better head on the gravity fed system (the old tank is very deep)? Originally my house had a back boiler which was gravity fed. It used 1.5 inch galvanised pipe for that. Although over the years we have replaced some of the pipe, a lot of my plumbing is lead. The main supply pipe is only 1/2 inch lead.
Pic of some ancient pipe iron pipe under the airing cupboard floor (no longer in use). For scale all of those copper pipes are 28mm except the one in the corner with compression fittings which is Imperial (1 inch cold to bathroom reduced to 22mm at elbow). The cold feed from tank to cylinder (not in picture) is still 1 inch iron, good flow through that. In case anyone wants to know the 2 pipes on the left are feed and return to cylinder and the one in the middle is hot water from cylinder.
Does anyone know why such big tanks were used? I am totally guessing but was it because the mains supply was unreliable or very poor in pressure? Might it also have been to try to get a better head on the gravity fed system (the old tank is very deep)? Originally my house had a back boiler which was gravity fed. It used 1.5 inch galvanised pipe for that. Although over the years we have replaced some of the pipe, a lot of my plumbing is lead. The main supply pipe is only 1/2 inch lead.
Pic of some ancient pipe iron pipe under the airing cupboard floor (no longer in use). For scale all of those copper pipes are 28mm except the one in the corner with compression fittings which is Imperial (1 inch cold to bathroom reduced to 22mm at elbow). The cold feed from tank to cylinder (not in picture) is still 1 inch iron, good flow through that. In case anyone wants to know the 2 pipes on the left are feed and return to cylinder and the one in the middle is hot water from cylinder.
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