On Fri, 24 Sep 2004 19:03:07 +0100, Peter Hawkins wrote:

The immersion heater in my house is of a type I haven't seen anywhere
else. There are no elements in the main tank. Instead the element is
mounted inside a small vertical cylinder plumbed into the side if the
tank but seperate from the main tank. Its mounted vertically with the
element upside down and fitted from the bottom (which makes it hard to
see the stat setting without a mirror). The secondary cylinder is 3
inches diameter and about 15 inches long.

A while back I noticed that running the immersion even for a short
time produced dangerously hot water. Ther was also a bubbling noise
from the cylinder when the immersion was on.

So I replaced the stat (7") set it for 60 and thought that would be
that. Same problem.

Any ideas....


I've only seen one of these once before. IIRC the secondary cylinder was
horizontal?

I believe that the intention is that hot HW becomes available more
quickly, and/or the whole cylinder is eventually heated through.
So it combines the best features of the top and bottom positioned
conventional immersion heaters.
It is normal for some noises to occur even with brand new immersion
heaters.
The replacement for this type would be an 11"(?) unit which contains a 7"
thermostat (cf 27" and 11")
It might be that all you need to do is to replace the thermostat (will
this mean you have to cut a hole in the floor ?!?).



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
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