What causes the combustion engine overheat during the operation of the gas-fired boiler?

Overheating in the combustion engine of a gas-fired boiler can be caused by several factors. Understanding and addressing these issues is crucial for maintaining the efficiency and longevity of the boiler, as well as for ensuring safety. Here are some common causes of overheating in the combustion engine of a gas-fired boiler:

Insufficient Water Flow: If there isn't enough water flowing through the boiler, it can't absorb enough heat from the combustion process, leading to overheating. This could be due to a malfunctioning pump, blocked pipes, or low water pressure.

Scale Build-up in Heat Exchanger: Over time, minerals in the water can deposit on the heat exchanger surfaces, forming a scale. This scale acts as an insulator, reducing the heat exchanger's efficiency and causing the boiler to overheat.

Faulty Thermostat: A malfunctioning thermostat might not correctly regulate the boiler's temperature, causing it to overheat.

Blocked Flue or Vent: If the flue or vent is blocked, it can restrict the expulsion of exhaust gases, causing the boiler to overheat. This blockage can be due to debris, bird nests, or other obstructions.

Air Supply Issues: Inadequate air supply for combustion can lead to incomplete combustion, generating excess heat. This might be due to blocked air intakes or mechanical failures in systems that control air supply.

Incorrect Gas Pressure: Too high gas pressure can lead to excessive heat generation. This might be due to a malfunctioning gas valve or incorrect settings.

Poor Combustion: Poor combustion efficiency can result in higher temperatures than normal. This could be due to various factors, including wrong air-to-fuel ratio, dirty or malfunctioning burners, or problems with the combustion chamber.

Faulty Safety Devices: If safety devices like high limit switches or pressure relief valves are not functioning correctly, they may fail to shut down the boiler in case of overheating.

Pump Failure: The circulation pump ensures that water circulates through the boiler and heating system. If this pump fails, water flow is reduced, leading to overheating.

Lack of Maintenance: Regular maintenance is crucial for the efficient operation of a boiler. Without it, issues like dirty burners, scale build-up, and faulty components can go unnoticed, leading to overheating.

In any case, overheating in a gas-fired boiler is a serious issue and should be addressed promptly. If your boiler is overheating, it’s advisable to turn it off and call a certified technician for inspection and repair. Regular maintenance and inspections can prevent most causes of overheating.