Honeywell T4 Thermostats, 24 → 230 V, +21 → +35 (Upper) °C, +5 → +21 (Lower) °C

Compatible with 24-230V on/off appliances such as gas boilers, combi-boilers and zone valves
The T4 can be used as a temperature sensing device in an S or Y Plan system
Well suited to control combination boiler installations or additional zones in an S Plan Plus system
Wireless communication between thermostat and receiver box with 30m range
Pre-bound to the wireless relay box, no need to establish a binding
On screen text display and function buttons to ensure simplified programming and operation for all users
Energy saving TPI control
Optimum stop & start & Delayed start features that learn how the room is heated
Two wire, volt free connections are ideal for use with combination boilers
Easy to fit with a three step installation process: Wire, Power Up and Test, Configure
New improved wall plate with extra wiring space
Optional Wired external sensor available (wired versions only)
On screen heat demand icon makes start up testing easy
Simple push button access to configuration menus
Adjustable Frost protection
Away mode with specific temperature set (number of days changeable)
Temporary schedule override until next set point or for 1 or 2 hours
Schedule can be turned off – will operate as a variable setting thermostat only
Displayed on an extra-large LCD screen
Automatic Summer/Winter time change
7-day programming with 7 day: 5/2 or single day schedules
Four or six independent time & temperature settings (default is 4)
Pre-configured 5/2 heating schedule|•Battery powered (with low-power indicator)
Easy change battery compartment
Optional backlight with extended light on time period
Burner 'ON' symbol

The T4 programmable thermostat is a modern a wired 7-day Programmable Room Thermostat. It is designed to provide automatic time and temperature control of domestic systems in domestic or light commercial premises.