How to improve my boiler’s thermal efficiency？

Scale buildup, worn parts and shifting operating conditions all contribute to lower heat transfer rates—and higher fuel bills. Here are four practical upgrades and practices to help your boiler stay efficient and reliable:

1. Add an Economizer

An economizer recovers heat from flue gases to preheat boiler feedwater. Raising feedwater temperature by just 10 °C can cut fuel consumption by roughly 1%, and an economizer retrofit often delivers ROI in under two years. Preheated water means less fuel burned to reach steam temperature.

2. Install a Flue Gas Heat Recovery Unit

Beyond economizers, dedicated heat recovery systems can extract even more energy from exhaust gases. By lowering exhaust temperature, you reduce wasted heat and can trim fuel use by 5–30%, depending on your boiler size and load profile.

3. Optimize Air–Fuel Mixing

Good combustion depends on the right air–fuel ratio. Too much air carries heat away; too little causes incomplete burning. Whether you adjust your existing burner controls or upgrade to an automated system, you can gain about 1% in efficiency for every 2% reduction in excess oxygen, all while protecting your boiler’s integrity.

4. Recover and Reuse Condensate

Steam condensate still contains significant heat—often more than 10% of the steam’s original energy. A condensate return system sends that warm water back to the boiler, cutting down on cold makeup water and the fuel needed to heat it.

New high efficiency steam boiler

View product information

Fangkuai Boiler established a Full-Condition Research Laboratory and invited Tsinghua University’s advanced technology team to join us. With over ¥20 million invested annually in R&D, our boilers consistently achieve over 95% thermal efficiency.

• In-House PLC Control System: Monitors operating data in real time and fine-tunes combustion for stable, peak performance.
• Full-Premix Combustion: Ensures fuel and air blend thoroughly for a cleaner, more efficient flame.
• Patented Wing-Tube Heat Exchanger: Finned tubes arranged like wings inside the flue lead to a 5× boost in heat transfer, allowing for shorter tubes and a more compact boiler footprint. Smooth outer walls resist scaling, reducing maintenance.
• Condensate Recovery: Captures leftover heat from return water to further lower fuel use.
• One-Stop Service: From design and manufacturing to installation, commissioning and ongoing maintenance, we handle every step.

Considering an upgrade or a new boiler installation? Contact us