The Horstmann Electronic 7 immersion heater timer has factory default settings of ON 2:15AM and OFF at 7:15AM after a reset. If you have an additional secondary boost at 5:00PM till 7:00PM also programmed, this will be charged at the day rate! so I would suggest that you have this set to a A boost button is provided to top up the hot water if supplies are running low and an automatic boost setting to provide a pre-programmed daily boost is also available. The Electronic 7 Series 3 is interchangeable with previous Economy 7 controllers using the standard size Economy 7 wall box and plug in connectors. with all past and present Horstmann Economy 7 controllers • Built in clock - automatic Summer/Winter hour change • Up to three off peak settings per 24 hours • Programmable and manual boost • Programme security feature • Suitable for use with single, dual or twin element immersion heaters ElEctronic 7 SEriES 3 Video: How to manually set your Horstmann thermostat (Centaurstat) Category Nonprofits & Activism; Show more Show less. Comments are disabled for this video. The Electronic 7 is designed to control one or two 3kW immersion heaters, utilising off peak electricity tariffs to provide a tank full of hot water each morning. Additional off peak settings are available to take advantage of the latest off peak tariff arrangements. Product Features Discuss Need help, setting horstmann economy 7 - it's just not working in the Electrical Forum area at ElectrciansForums.co.uk. First thank you for reading and helping out. Ok I got the above water timer, since last week it's just doesn't seem to be working. First off i set the time as per current Created Date: 11/2/2007 4:35:02 PM See more like this Horstmann - ServicePlus Series 2 Interval 7 Days Timeswitch - S17R - New. Horstmann H37XL Channelplus Electronic Central Heating Programmer Series 2 - 3 c. Save horstmann electronic 7 series 3 to get e-mail alerts and updates on your eBay Feed. Search refinements