They heat up overnight. Mine come on about 10.30pm and turn off at 7.30am. It stores the heat overnight and you can release the heat through the day. Leave the heater on and set the room control temperature control to 1 when you get up in the morning you can turn the room control up and it will open the vent to let the heat out. They take some getting used to we moved in our house 18 years ago and this system was already in we are just about getting used to how it works after all this time
shazjb
February 2009