The whole thread is about Hive, I will admit I don't have Hive, I have Wiser, and I will also admit my Wiser systems is not all Wiser but a mixture of many different makes, but be it Wiser, Hive, EvoHome it does not really matter, the whole idea is the TRV is king, and the hubs, programmers, or what ever name is given to the base unit, is designed to allow the TRV to fire the boiler, this is how these so-called "Smart" systems raise above the rest, and allow a massive reduction in energy used, as rooms only heating as and when required, and the "when" is an important part of this, and as yet not seen a pure mechanical head where one can set the "when".
There are I will admit alternative systems, EPH does one, where hard-wired zone valves are used, and the thermostats are set as master and slaves, but we are not talking about that system, we are talking about a system which uses the TRV to produce zones, but with Hive it has progressed over the years, so there is no single Hive system. In the early days it had a 22°C limit on the wall thermostat for the unit to accept demands for heat, and it did not have the OpenTherm option.
This makes talking about Hive a problem, as there were some odd features, in some cases very good, Hive can work with C Plan where it seems Wiser ignored that function, which was one reason I was looking at Hive, as my system is running on a C Plan, but I got around the problem by retaining Nest Gen 3 to work domestic hot water if required, but I am not trying to claim my hybrid system is Wiser, Nest, Kasa, eqive, or Energenie, I freely admit it is a mixture, and it may not work the same as a single system, it was you who said you have Hive, not Hive plus some other random makes and models, you said Hive, and the whole idea of the modern systems is the TRV is king.
There are always exceptions, and I see no reason not to use just part of a system to do the bit you want, be it geo-fencing, or internet weather compensation, or simply using it through the phone or with voice commands, that is after all what I have done, but I don't claim to be running a pure Wiser, Nest, Kasa, eqive, or Energenie system. I made some mistakes, and started with Nest, which did not do as it said on the tin, so I had to move to a system which will do as I want, but have the leftovers from my failed attempts. Wish I had gone with Wiser to start with.
That's my battery changed. 
and not easy to find battery state main page click this 
