Just happened to be rummaging around on the Wiser web site and looked in more detail at what options they have for different systems. It appears that what they think is a "gravity" system has no pump whatsoever, not sure how well heating would work if it's totally dependent on convection! The next step up for them is a fully-pumped (vented) system with motorised valves and a cylinder thermostat.
So they just don't recognise what I though was (once) a pretty common UK setup (what I call a "gravity" system) which has a convection circuit to heat the hot water tank and a pump for the radiator circuit, all topped by open header tank(s) in the roof space. Our system didn't even have a cylinder thermostat when installed but I added one soon after we moved in.
This lack of recognition is particularly weird as my previous controller, made by Drayton, had a specific setup jumper for such systems. And it must be trivial to enable in software!
So they just don't recognise what I though was (once) a pretty common UK setup (what I call a "gravity" system) which has a convection circuit to heat the hot water tank and a pump for the radiator circuit, all topped by open header tank(s) in the roof space. Our system didn't even have a cylinder thermostat when installed but I added one soon after we moved in.
This lack of recognition is particularly weird as my previous controller, made by Drayton, had a specific setup jumper for such systems. And it must be trivial to enable in software!
