Panel heaters with mechanical thermostats are cheaper, than with electronic, but their disadvantage is that they are slow to react to changes in temperature in the room. If the electronic thermostat maintains the temperature with an accuracy of ± 0,1 0
С, then the mechanical thermostat's accuracy is ± 1 - 3 0
С. And a mechanical thermostat issue additional sounds (bimetallic plate responds to changes in temperature), when the electron runs completely silently. The mechanical thermostat advantage is that he is more stable in power swings. If the electronic thermostat can withstand, without burning the long-term increased in voltage to 250 V and short-term to - 270 V, the mechanical thermostat can withstand that kind of increase without problem. Lowering the voltage does not affect both thermostats, but, then the heater loses power, he less gives heat to the room. Following diagrams show how the mechanical and electronic thermostats react to an additional source of heat.
The reaction amplitude of mechanical thermostat to additional source of heat:
The reaction amplitude of electronic thermostat to additional source of heat:
Then you choose the heater, you should pay attention not only on price of heater, but what kind of thermostat is installed in it. Heaters with electronic thermostat more expensive, but their advantages over heaters with mechanical are that will be less temperature variation, save up to 5% energy because of less variations and they work more silently.