Case Study Number 1: Vented hot water cylinder. Flat roof
Sue King’s installation was very straightforward with no significant problems.
The first job was to replace the existing hot water cylinder with a vented twin coil unit from Gledhill. This cylinder was much larger at 166L compared to 120L, but installed in the same location as the original cylinder.
It was decided to install the collectors on the flat roof of the utility room. This allowed the collectors to be directly over the hot water cylinder. This enabled a very short pipe run, which in turn allowed for very little heat loss through the pipes.
The only cause for concern, since the collectors were to be installed on a flat roof, was to make sure that the pipe run through the roof was watertight. This was achieved with the help of lead flashing, felt and bitumen, which made for a very watertight fitting.
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