Having replaced our boiler with swale heating we were surprised it had appeared to have stopped working after just 17 months we called out a heating engineer who traced the problem to the thermostat the batteries had run out , we did not ask for, or want a "wifi " thermostat as they are unreliable, the swale electrician had cut the wires to install the new one without even informing us I was advised by the person on the phone if we wanted a wired one we would have to pay, as according to them he had fitted the thermostat at great cost £190 !! Free , a quick check online showed this to be a huge exaggeration they retail at around £80 and I would question that it was fitted free of charge we are now stuck with a thermostat we would never have had installed... shameful !!