This is a replacement timer providing up to 17 on/off periods each day. It is a 7-day timer and can be programmed with all days the same or with different programmes for each day of the week.

It will replace any Diehl 880, 887, 890 or 897 240v single-channel timer but please note that the terminals are on the bottom of the timer, not the top as on the Diehl, but it comes with instructions that show you how to reposition the terminals.

Your existing timer may have either 4 or 5 terminals. If it has 5 that is because it is a general purpose timer made to control air-conditioning and all sorts of other devices. You will note that there are only 4 wires connecting to your timer and the fifth terminal is not used. 

Our timers are specifically made for boilers without the redundant fifth terminal thus eliminating the confusion of how to connect 4 wires to 5 terminals.

It measures 60x60mm with mounting holes at 54mm centres.

Supplied with full instructions.