A Wood Pellet Fired Batch Fryer with an Outside (External) Heat Exchanger is an advanced industrial setup designed to maximize oil quality and fuel efficiency. Unlike direct-fired fryers where the burner sits directly under the pan, this system uses a remote burner and a separate "Shell and Tube" heat exchanger.

The edible oil is continuously pumped from the fryer, through the heat exchanger (where it is heated by the pellet fire), and back into the fryer. This indirect heating prevents the oil from touching a flame-heated surface, which significantly reduces oil carbonization.

1. How the External Heat Exchanger System Works

1. Pellet Combustion: Wood pellets are automatically fed into a burner. The flame stays inside a refractory-lined chamber, away from the oil.
2. Heat Transfer: Hot flue gases pass through a Shell and Tube Heat Exchanger. Edible oil circulates through the stainless steel tubes while the fire heats the shell.
3. Continuous Circulation: A high-temperature centrifugal pump keeps the oil moving at high speed between the fryer pan and the exchanger.
4. Temperature Control: A digital controller regulates the pellet feeder. Once the oil reaches 180 C the feeder slows down to maintain a steady temperature.

2. Technical Specifications (Industrial Batch Model)

3. Key Benefits of "Outside" Heat Exchanger

• No Oil Burning: Because there is no direct flame under the pan, "hot spots" are eliminated. Your edible oil stays clear for much longer.
• Easy Cleaning: Since the heat exchanger is separate, the frying pan is just a simple tank that can be cleaned easily with a pressure washer.
• Safety: The fire source can be located in a separate room or behind a partition wall, keeping the frying area cool and reducing the risk of oil fires.
• High Production: External exchangers can deliver much higher heat loads than inbuilt coils, allowing you to fry 100–150 kg/hr in a single batch pan.