The ESi Controls Y Plan kit comprises of a 2 channel programmer (ES2247B), 3 port motorised zone valve (ESZV223), electronic room thermostat (ESRTE2), clamp-on cylinder thermostat (ESCTS) and a 12 way wiring centre (ESWC1). The ESi Y plan kit provides fully independent time and temperature control of the heating and hot water in pumped domestic central heating systems. Ensuring that when both the heating and hot water demands are satisfied the boiler and pump are switched off by the controls. This standard Y plan kit meets the requirements of Part L of the building regulations and if required can also be easily extended to include full control for a second heating zone (a building regulations requirement in homes larger than 150m2). There is also the opportunity to upgrade to a programmable room thermostat and a single channel programmer to provide full temperature control right through the day. And if an additional heating zone is required, this can be facilitated by the addition of an additional two port zone valve and either upgrading to a three channel programmer and another electronic room thermostat, or by adding a programmable thermostat. The kit comes pre-boxed and is an economical solution for any Y Plan system. Economical Pre-boxed Quick installation 3 year warranty Easy annual maintenance Easy fit backplates Factory set time and date with automatic BST/GMT 1 hour time change Simple user operation http://www.esicontrols.co.uk/es2yplan.html