V
Vic Dones
Hi. I'm hoping someone can help me to understand how our hot water system works (or maybe isn't!). We have had a new unvented system for hot water and heating put in. The gas boiler is the original one. Our problem is with the hot water. We get a cylinder full of hot water, which is good. But then someone can go and take a shower for 10 minutes and there is no call to reheat the water in the cylinder. So when an unsuspecting person then showers even several hours later the water runs tepid on them. At some point the call for heat is recognised and the cylinder reheats fine. So my question is: If the cylinder stat is set to 65C, this is the temperature of the water when heating stops. But what triggers the call to reheat again? Obviously if you had a full cylinder of hot water and only ran off 5litres you wouldn't expect the system to reheat. So, how does the system know the cylinder is cold enough to need to reheat? Our heating engineer has told us that the stat is working fine, but he couldn't explain how he knew that. Please could someone explain the mechanism to me? Many thanks
