Zonal heating issues

[Al81]

I moved into a new build 5 years ago and don't think the thermostats/heating has ever worked properly. I have 2 Siemens Rev24 thermostats and an Ideal Es35 boiler, running 2 heating zones (upstairs and downstairs). I programmed both thermostats with the same start and finish time, same comfort temp, everything is identical. When using the timer function, only the downstairs rads come on at the required time. All upstairs rads are permanently on despite the timer function being set. I've had to resort to turning the boiler off when no heat is required (leaving hot water on) and turning the boiler back on when we need to warm the house. Admittedly, I'm rubbish at DIY and wouldn't have a clue where to look for a solution. From what I've read online, it could be a zone valve that is faulty and constantly asking the boiler for heat?? Any tips or advice would be greatly received

 

[Chuck]

IFrom what I've read online, it could be a zone valve that is faulty and constantly asking the boiler for heat?? Any tips or advice would be greatly received

If the zone valve that controls the upper zone has been left in its 'locked open' setting, that would explain the symptoms. You need to find the zone valve. It will have a small manual setting lever. Have a look at that and try moving it gently. Upload a picture and tell us what it felt like when you try moving it.