Thermostat Signals for Heat:

The process begins when the thermostat detects that the room temperature has dropped below the desired setting. The thermostat sends a signal to the boiler, indicating that heat is needed.

Fuel Supply and Burner Ignition:

Once the signal is received, the fuel supply is activated. Depending on the type of steam boiler, the fuel may be natural gas, oil, or another source. The burner ignites, generating a controlled flame to heat the water in the boiler's vessel.

Water is Heated in the Boiler:

As the burner heats the water inside the boiler, the water begins to reach its boiling point. The heat energy from the burner turns the water into steam. This transformation occurs within the boiler's heat exchanger, which is designed to transfer heat efficiently from the flame to the water.

Steam Rises and Distributes to Radiators:

Once the water turns into steam, it naturally rises due to its lower density compared to water. The steam is then pushed through a network of pipes to radiators located throughout the home. The steam enters the radiators, releasing heat and warming up the rooms.

Condensation and Return to the Boiler:

As the steam cools down in the radiators, it condenses back into water (called condensate). This water flows through the return pipes to the boiler. The boiler reuses this water, minimizing waste and increasing efficiency.

Pressure Control and Safety Mechanisms:

Steam boilers are equipped with pressure control mechanisms to ensure safe operation. The boiler's pressure control device monitors and maintains the steam pressure within safe limits. A pressure relief valve will activate if pressure exceeds these limits, releasing excess steam to prevent dangerous conditions.

Cycle Repeats:

The boiler continues cycling on and off to maintain the desired indoor temperature. Once the thermostat detects the set temperature has been reached, the boiler turns off until the next heating cycle is required.