The temperature control accuracy of +/- 0.5C and different TPI settings – for gas, oil and electric systems – will reduce the temperature swing that normally occurs with older style thermostats. As a consequence these thermostats will help to save energy as the control algorithm allows the boiler to operate in condensing mode for longer periods.A perfect partner for use with the Horstmann Programmers and Zone Valves. · · · 230 volt mains operation · · Ensures heating will switch on whenever frost conditions are detected · · Internal setting dial · · Temperature setting range 0-20C · · Wireless or wired (battery operated) versions · · Load compensation