So I'm still confused what temperature sensor to buy

[MisterBoy]

I am building an EvoHome system and in one room, the HR92 is clearly not getting a good airflow - it claims the room is 21.5C when the thermometers I have tested around the room in just about every location claim it is 15C.

So I want to get a dedicated sensor which I know is possible. I go to the website and select Honeywell Evohome->Wireless Thermostats, on the assumption this will show only EvoHome compatible devices https://theevohomeshop.co.uk/25-wireless-thermostats. Barring versions with/without relay boxes - with an existing EvoHome controller setup I don't need this right? - there are apparently 4 options:

• Honeywell T87RF2033 Single Zone Thermostat £74
  
• Honeywell DTS92E1020 Wireless Digital Room Thermostat £60
  
• Honeywell HCF82 Wireless Room Sensor £64 (out of stock)
  
• Honeywell HCW82 Wireless Room Thermostat £72 (out of stock)
  

I haven't the faintest idea if they are all able to do what I want and what the differences are - they all claim EvoHome compatibility. Are they all battery powered? Are the HCF/HCW for people who like to pretend it's the 70s?
The top one looks nicest but the DTS92 is the one I've seen mentioned before.

I want to buy one and have no idea what to do!

[Bart]

I used a T87RF2033 for this purpose.
DTS92E1020 should work as well.
The remaining 2 seem to be suited as well, never looked closer at them though, their cost seems a bit high.

Note that only the HCF82 is just a sensor.

[Richard]

I suggest you stick with the T87RF or the DTS92E...