Bad thermostat systems can cost you a lot of money and actually can ruin your home heating and cooling system so if you think you might have a bad thermostat system by all means get that replaced. What we are talking about essentially is a digital touch screen that's tied into a sensor, temperature sensor and it's programed to tell you or your heating and cooling unit on when to turn off. So the things you want to look for if lets say you have an air conditioner if it's programmed to cool your home to a certain temperature and then shut off, if it's bad you'll find that the air conditioner comes on and it doesn't turn off. If that's happening you could definitely burn out your AC unit so you don't want that. It's much more expensive repair then the thermostat system itself. So go to your local home repair store and take a look at what systems are available and how they handle what you need to do. Some people only need to have a system that controls one unit, some may have multiple units that need to be controlled. There are a lot of possibilities but you have to make sure that you know exactly what your system is that needs to be controlled and then and only then can you determine exactly what thermostat system is going to be best to control your particular units. But by no means should you overlook a bad thermostat system. If it's going bad you need to get it replaced as soon as possible. The longer you wait the more it's going to cost you. And if you happen to be doing a contract for somebody else, if they think it might be bad don't worry about trying to fix it and make it work it's always better if you think a system might be bad it probably is. So take it out and put in a new one and save yourself a lot of headache down the road.