There are multiple ways to control heating systems:

• “start-shutdown” or “on-off” control,
• proportional control (P),
• proportional-integral control (PI),
• and proportional-integral-derivative (PID) control

The “on-off” method will run your heating until the room (measured) temperature equals the set (desired) temperature and then switch off. With this method, the actual temperature will be higher than the temperature setting after the heater is switched off. This method does not account for thermal inertia and causes discomfort and unnecessary costs.

The Delta Dore thermostats use proportional-integral regulation (PI). This type of control continually adjusts the operating time based on the difference between the room temperature and the set temperature. For example, the heating may switch off when the room temperature is lower than the set temperature because the thermostat knows the required temperature will be reached through thermal inertia; no additional energy is required. Alternatively, the heater may switch on at the set temperature in anticipation of a temperature drop.

Proportional-integral regulation accurately maintains the set temperature without overheating or excess energy consumption. It improves comfort and can provide energy savings of up to 10%.