Whichever Hive thermostat you have, you'll find the guides here.
Hive Active Heating 2 Wireless Thermostat
Model: SLT3 / SLT3b
This is our wireless thermostat for combi and conventional boilers. It's wireless so you can move it around your house and make sure the temperature is right where you are. If you have a conventional boiler you can also use it to control your hot water. It takes 4x AA batteries.Product pages Welcome Guide (PDF) Installation Guide (PDF) User Guide (PDF)
Hive Active Heating 2 Wired Thermostat
This is our wired thermostat for combi boilers. It's a good option if you want to connect it to your existing thermostat's wiring and put it in the same place. It's also a good option if you have a larger home or one with thick walls, or if your boiler is hard to reach. It takes 3x AA batteries.User Guide