I guess the thermostat that I've mentioned is for the immersion heater.



"Christian McArdle" wrote in message et...
What is a zone valve, and what are the controls to make my HW
connections more efficient?

There should be a zone valve capable of shutting off the hot water flow
through the cylinder coil. This valve would be wired to open only when (a)
the programmer told you to heat the water and (b) the cylinder thermostat
said the cylinder wasn't hot.

You say there is a thermostat "on top". Normally the cylinder thermostat is
between the bottom and halfway up (but higher than the bottom coil tapping).
Are you sure the thermostat you mention isn't part of the immersion heater?

Christian.