The Vaillant printed circuit board is the boiler central control. By using the thermostats, sensors and switches, it keeps an eye on every procedure. It also enforces safety rules, ensuring that the boiler shuts off if any internal readings indicate a problem with the boiler's internal operations. Since it is programmed to make sure everything is operating as it should, the printed circuit board can be thought of as the boiler's brain.

Brand Name	Vaillant