If a building has multiple boilers, you may be able to use the boilers in sequence to prevent repeated cycles. If you use boilers that do not adjust, it is better to use the next boiler when the capacity of one boiler is full, instead of disconnecting and connecting several boilers that are loaded. On the other hand, in regulating boilers, the efficiency of the boiler increases in the load-sharing situation. Therefore, using several boilers at the same time in load sharing mode is more beneficial than using one boiler with % efficiency. Figure shows the relationship between ignition rate and efficiency in boilers with adjustable air and fuel flow utilization.

The burner combines fuel and oxygen to create combustion conditions with the help of a combustion device. This combustion takes place in a combustion chamber and the heat generated is transferred to the heat exchanger water. The controls regulate the combustion process, the ignition rate of the burner, the required fuel, the amount of air required, the water temperature, the steam pressure and the pressure of the engine boilers.

To increase the overall efficiency of the boiler, the heat released from the combustion process must be properly transferred into the fluid used. Any heat that is not transferred to the fluid is lost through the body of the boiler or the flue gas. The temperature of the gas inside the chimney is a good indicator of the heat transfer process and therefore efficiency. There are practical limitations to the low flue temperature. Its temperature will be higher than the fluid used in the boiler. In boilers that do not do distillation, the temperature should be high enough that water vapor does not distill in the exhaust chimney and clean the heat transfer surface in the distillation that causes corrosion. Condensing boilers that use natural gas are made and designed with accessories that are resistant to corrosion. Also, their chimney temperature can be less than . degrees Celsius. Trapping heat distillation increases efficiency by more than %.

In facilities, in addition to limiting, the system activity sequence is also important to achieve energy efficiency. Nowadays, with the general use of VAV (variable volume) systems in commercial complexes, simultaneous heating and cooling and overheating of the primary air are often ignored. Applying boiler restrictions based on outside air temperature, for example when the temperature is above . degrees Celsius, is an effective way to prevent this situation.

Cast iron boilers that are cross-sectionally cast iron are another type of engine room boiler that is used to heat commercial premises. These boilers do not use pipes, but instead, have cast-iron sections with water and combustion gas corridors. The cast iron parts are screwed together and look like a steam radiator. These parts are connected to each other by fireproof washers. These boilers are used to produce steam or hot water and are available in sizes from , to , BTU.