Can Hive smart thermostat downstairs be used in conjunction with 'dumb' thermostat upstairs?


I have a standard (non-combi) oil boiler and an 'S plan' heating system. I have separate thermostats for upstairs and downstairs but these are not separate zones on my timer control. The heating and the hot water can be separately selected - but the heating is either on or off. The upstairs and downstairs radiators are then operate based on the temperature set on the two thermostats. But, for example, I can't select only upstairs or downstairs to be on. The heating is either on or off.
Question 1:
Can fit a new Hive thermostat/receiver to replace the downstairs thermostat and leave the old 'dumb' thermostat to control upstairs? So depending on the temperature it's set to, it may come on when I turn on the heating on using new smart thermostat but can't be selected independently.
Question 2:
If I install Hive smart TRVs on two upstairs bedrooms, turn off all the other radiators upstairs and set the upstairs thermostat to maximum (so it's calling for heat), could these allow me to control temperature of these two bedrooms independently overnight?
We can't do this at the moment as the upstairs thermostat is on the landing which is a lot warmer than the bedrooms. The smart TRVs should, I think, allow us to have the rooms individually controlled - my hope is that if they call for heat, the heating will come on and if the upstairs dumb thermostat is set to max, they will then heat up. So they create two new zones effectively.
Can the smart and dumb thermostats work together in this way?
Thanks in advance for any wise words.
All the best
J
Replies
Question 2, might work in theory but there will probably be issues, I don't know if the TRV's would work completely independently of the other hive? why not just buy the wiser kit 3 for £156 and 2 x smart TRV's for another £70, then you will have full control, rather than a bodged up system.
I have tonight written a grumpy email to Hive as my Hive mini is disconnecting pretty much every day, despite purchasing a hub signal booster and having full Wi-Fi signal in the rooms with the hub, receiver and thermostat.
As I type, the heating has gone offline for the third time this evening and we are at 14.8 degrees. At one point after resetting everything again, the app was happily telling me everything had full connection and sitting at 21 degrees. (Not a chance). Half an hour later, the heating is chugging away and yet the app and thermostat tell me it is offline. I have put it in stand-alone mode again and am about to light the wood burner.
Hmpff. Goes to check out Drayton…
One of the issues is that (as you say above) it often tells you something different from what is actually going on at the time. I find that by checking the graph function, you can see whether the app is actually up to date or not. If not, refreshing it a couple of times until that screen looks right means that the data has updated properly, at which point the controls conform with reality.
When it works it is easy to use, I just can’t rely on it to actually do so.
My one Smart TRV - bedroom - works a treat too - gets bedroom warm(ish) for the morn.
Now my app says offline, the thermostat says no signal and yet the heating has decided to turn on.
I also installed a two-zone system in a village hall, and had some problems setting/connecting it up. I went on 'chat' with Hive, and they talked me through it in real time, and even remotely sorted a Hub issue. I was really impressed.