Digital central heating \/ hot water programmer for gravity or fully pumped systems. Ideal replacement for the older outdated analogue type programmers. It also Incorporates a room thermostat & frost protection if required. Using the industry standard back plate it will replace the following: Sunvic, Honeywell, ACL, Randall, Sangamo,Potterton, Horstmann, Smiths, etc., without the need to re wire. All wiring & fitting instructions included.12\/24 hour clock format. Daylight saving time changeover. 7 day \/ 5+2 day \/ daily (24hour) programming format. Max. 3 on \/ off programs per day for each channel. Each channel (CH or HW) is independently programmable. BOOST function: extend the current program by 1 to 3 hours. ADV (advance) function: reverse on \/ off output status, until next opposite setpoint. HOLIDAY program: may be scheduled upto 60 days in advance. Shortest switching time 10 minutes. For use in pumped or gravity installations (option user selectable). LED backlight, blue in colour. Backlight modes (user selectable): auto or on (default). Channel on \/ off status indicated by yellow and red LEDs. Non-volatile EEPROM memory to retain user settings when mains power is disconnected. Battery backup for clock (3V lithium CR2032). Temperature control function (1 °C resolution), display range -9.9 to +50 °C, temp control range +5 to +35 °C (20 °C default) and also frost protection. Power consumption 8VA \/ 250 V ac. Contact rating: Voltage-output rating 250V ac \/ 3A (1A). Ambient temperature: 0 to 35 °C. Dimensions 125 x 89 x 35 mm (lid closed). Standard BS wiring backplate with transparent polycarbonate terminal coverProgram Duration = 24 h, 7 daysNumber of On\/Off Cycles Per Day = 3Contact Rating = 1 A, 3 ASupply Voltage = 230 V ac