Hello, it can be for three different problems, one of the possibilities, is that the automatic (thermostat) is damaged, a second possibility is that as a safety rule so that the device does not boil the coffee or catch fire if the automatic is lock, in the metal base, where the resistance that produces heat is housed there is a thermal fuse that is in physical contact with said metal body, is a metal cylinder with two legs (one on each side) by means of which connects it, it measures about ten millimeters by four or five in diameter and is placed inside a silicone spaghetti to electrically isolate it, attached to the metal base by means of a medium ohmega type clamp, fixed with a screw to make it heat transmitted from said base to it depending on the device for which it is manufactured, is calibrated for different temperatures can be 80 ° C or so depending on the case, it is very frequent that said f usable after some time of use is damaged (melts) and for that reason it stops circulating electricity through it and as a result the device no longer heats, if it is the first possibility, the automatic one (thermostat) could be that by normal use, the platinum that connects the device to heat the coffee and when it reaches the proper temperature, disconnect the resistance, the worn out contacts (such as two drops of Silver alloy metal), and for that reason not work, every Once the automatic disconnects the resistance, there is a spark that, as time goes by, causes them to wear out to the point of not making more contact, so the automatic must be replaced, (it is also manufactured calibrated for different temperatures depending on of the device in which it is used) and the last is that the resistance has burned. the cost of the thermal fuse is close to fifty pesos, the automatic depending on the type of the same can be around three hundred pesos or something else and if it were the resistance (heater) I do not know if the replacement of it is justified, since It is the base of the coffee maker and is the heart of the device. I hope I helped you, my apologies for the explanation. good luck.