Hive dual zone

[EricMark]

They aren’t Hive though are they?

True, and not sure what percentage of Hive would be required? Two Hive TRV heads same price as extra Hive wall thermostat so if combining zones can use single Hive wall thermostat with two Hive TRV heads in the critical rooms, the much cheaper eQ-3 TRV heads will stop rooms heating but will not tell the Hive wall thermostat to switch on, so question is how many Hive and how many eQ-3 are required to control the home.
Personally I would start with one Hive TRV head in coldest bedroom and Hive wall thermostat in main living room and test it out, if rooms are warm enough then all it needs is to reduce temperatures in rooms when not used by fitting eQ-3 heads.

 

[123]

@EricMark I wouldn't call it zoned if the room can't call in the boiler, all that seems to be is a digital type of TRV.

 

[EricMark]

Unfortunately Nest which I have has withdrawn support for MiHome, so all my TRV heads are now not linked to main wall thermostat, however they do control the house reasonably well with each area other than hall having a different schedule, there has to be some thought, in the morning the hall wall thermostat changes temperature in a number of small steps to ensure boiler running when there is a scheduled change, but it does work well.

Hive has an advantage over Nest, it actually has a dedicated TRV head which can send a "demand for heat" to the wall thermostat, but for an example if two children go to bed at 8 pm then only one room needs a Hive TRV head, the other bedroom could have a cheap eQ-3 head as the one Hive head has triggered the boiler.

So if the Hive wall thermostat is where one original thermostat was, and there is a Hive TRV head where the other thermostat was, and you fit cheap eQ-3 heads in other rooms served by the other thermostat you have a better than original system.

 

[davesparks]

This is sounding very complicated for the average homeowner who just wants to turn their heating on ans off.

What powers these electronic TRVs?

 

[EricMark]

All my TRV heads use two AA batteries which last around two years, the only change to the old head is temperature shown as ºC and they have the ability to set to more than one temperature through the day/week, open window detectors and twin settings Eco and Comfort which on can swap with touch of a button.

I don't know what you do, but I allow the home to cool over night, and day set slightly lower than evening. Without the electronic heads you can still set the programmable wall thermostat to reduce temperature over night, but as soon as you drop the temperature you lose the balance between rooms. So the setting of the lock shield valve becomes critical, it is not so critical when using programmable TRV heads.

The other problem without programmable TRV heads the sun can really mess things up, the room temperature can rocket when sun hits large windows, and although the electronic TRV is slow to adjust, it is twice as fast as a mechanical type.