The LP522 programmer is a mid-level programmer that provides distinct heating and hot water schedules. The LP522 offers a 5-day / 2-day program option that lets you configure distinct 'on' and 'off' periods for weekdays and weekends to fit your schedule. Each day, you can arrange up to three different heating and hot water intervals. The advance boost button can be used to provide 1, 2, or 3 hours of heating and/or hot water in advance of your chosen time periods, saving you the time and effort of having to reprogram if you need a one-time burst of heating or hot water. On weekdays and weekends, the LP522 gives versatility to folks who have quite varied living habits. If you need daily flexibility, ourLP722 may be better suited to your needs. The same spec as the LP522 but with Service Interval It's easy to use the programmer for 5 days and 2 days Heating and hot water have their own timers. Automatic summer/winter time updates are pre-programmed into the clock. Memory saves function Each program has three time control periods. Switching options include on/once/timed/off. Backlit screen for easy reading To temporarily advance the heating, press the Boost button.