How to Bleed Oil Combi Boiler: A Comprehensive Guide

Bleeding an oil combi boiler is a crucial maintenance task that ensures the efficient and safe operation of your heating system. This comprehensive guide will walk you through the step-by-step process of bleeding an oil combi boiler, providing you with the necessary tools, technical specifications, and expert insights to help you tackle this task with confidence.

Tools Required for Bleeding an Oil Combi Boiler

  1. Pipe Wrench or Allen Key: A sturdy pipe wrench or Allen key is essential for loosening the bleed screw on the fuel pump. The size of the wrench or Allen key will depend on the specific make and model of your oil combi boiler, so it’s important to have the right tool on hand.

  2. Small Container: You’ll need a small container, such as a plastic or metal bowl, to catch the oil that drains out during the bleeding process.

  3. Rubber Gloves and Rags: Wearing rubber gloves and having clean rags on hand will help you handle any spills or drips, keeping the work area clean and safe.

Steps to Bleed an Oil Combi Boiler

How to Bleed Oil Combi Boiler

  1. Turn Off the Boiler: Before starting the bleeding process, ensure that the oil combi boiler is completely turned off and disconnected from the power source.

  2. Locate the Bleeder Valve/Screw: The bleeder valve or screw is typically located on the fuel pump, usually near the oil line inlet. Consult your boiler’s manufacturer manual or do a visual inspection to identify the exact location.

  3. Position the Container: Place the small container underneath the bleeder valve/screw to catch the oil that will drain out during the bleeding process.

  4. Loosen the Bleed Screw: Using the appropriate pipe wrench or Allen key, gradually loosen the bleed screw, but do not remove it completely. This will allow air to escape without causing a high-pressure spill.

  5. Press the Reset Button: Once the bleed screw is loosened, press the reset button on the boiler. Keep the wrench or Allen key ready to tighten the screw again.

  6. Listen for Air Escape: As you loosen the bleed screw, you’ll hear a hissing sound as air escapes the system. This will be followed by a mixture of oil and air. Continue to monitor the flow until it becomes steady.

  7. Tighten the Bleed Screw: Once the flow becomes steady, indicating that the air has been fully bled from the system, use the wrench or Allen key to securely tighten the bleed screw.

  8. Replace the Casing: After the bleeding process is complete, replace the boiler casing and ensure that all components are properly secured.

Technical Specifications

Bleed Screw Location

The bleeder valve or screw is typically located near the oil line inlet on the fuel pump. The exact location may vary depending on the make and model of your oil combi boiler, so it’s important to consult your manufacturer’s instructions or do a visual inspection to identify the precise location.

Bleeding Process

The bleeding process involves loosening the bleed screw, allowing air to escape the system, and then tightening the screw once a steady flow of oil is achieved. This process helps to remove any air pockets or blockages in the fuel line, ensuring the efficient and safe operation of the oil combi boiler.

Reference Links

  1. How to Bleed an Oil Boiler
  2. Bleeding an Oil Boiler: Step-by-Step Guide
  3. Bleeding an Oil Combi Boiler

By following the steps outlined in this comprehensive guide, you can effectively bleed your oil combi boiler, ensuring optimal performance and prolonging the lifespan of your heating system. Remember to always prioritize safety and consult your manufacturer’s instructions if you have any doubts or concerns during the process.