Swimming Pool Blog - Tips, Care, and Installation

How To Blow Out Pool Lines

Written by Team Royal | 9/25/24 4:04 PM

Blowing Out Pool Lines

Proper pool winterization is essential to prevent costly damages during the cold season. One critical step in this process is blowing out the pool lines to ensure they are free of water, which can freeze, expand, and cause significant damage.

Table of Contents
Importance of Blowing Out Pool Lines
Pumps And Tools to Blow Out Your Pool
How Low to Drain Your Pool
Step-by-Step Guide to Blowing Out Pool Lines
Sealing and Protecting Pool Lines
Frequently Asked Questions

 

Importance of Blowing Out Pool Lines

Blowing out your pool lines is a critical step in the winterization process, especially for those in colder climates. Here’s why it’s so important:

  • Prevents Water from Freezing in the Pipes: Any water left in the pool lines can freeze and expand, leading to cracks and bursts in the plumbing. This can cause significant damage that is expensive to repair​​.
  • Avoids Expansion That Can Cause Pipe Bursts: Water expands when it freezes, exerting pressure on the pipes and fittings. Blowing out the lines ensures there is no water left to freeze and cause damage.
  • Protects Your Pool’s Plumbing System: By removing water from the lines, you safeguard the entire plumbing system, including the pump, heater, and filter, from potential freeze damage​​.
  • Ensures a Smooth Reopening in the Spring: Properly winterized pool lines mean fewer issues when reopening your pool. This can save time and money on repairs and maintenance​​.

In addition to these points, consider the regional climate. If you live in an area where temperatures drop below freezing, blowing out the pool lines is a necessary step. In milder climates, it may be less critical but still beneficial as a precautionary measure against unexpected cold snaps​.

 

Pumps And Tools to Blow Out Your Pool

  1. Air Compressor:
    • Air compressors are powerful and versatile, making them ideal for large pools. They can generate the high-pressure air needed to blow out water from the pool lines efficiently.
    • Use with caution to avoid over-pressurizing the pipes, which can cause damage. It’s important to control the pressure to ensure it stays within safe limits​​.
  2. Shop Vac:
    • A shop vac, particularly the large canister types with a capacity of 5 horsepower or more, can be effective for smaller pools or specific areas such as skimmers and return lines.
    • While useful, shop vacs are generally not as efficient as specialized pool blowers and may struggle with main drain lines due to lower pressure capabilities​.
  3. Specialized Pool Blowers:
    • Designed specifically for pool lines, specialized pool blowers provide consistent and safe pressure, making them the most reliable option for this task. They are engineered to avoid over-pressurizing while delivering the necessary airflow to clear the lines completely.
    • Devices like the Cyclone Pool Blower are highly recommended due to their efficiency and safety feature​.
  4. Adapters and Fittings:
    • These are necessary for connecting your blower to different pool fittings, ensuring a secure and effective seal. Proper adapters and fittings are crucial to direct the airflow correctly and maximize the efficiency of the blowing-out process.
    • Ensure you have the correct size and type of adapters for your specific pool setup to facilitate a smooth and thorough winterization process​​.

 

Preparing for Winter: How Low to Drain Your Pool

  1. Lower the Water Level: Drain the pool water to below the skimmer level, typically 4 to 12 inches.
  2. Turn Off the Pump and Heater: Shut down all equipment to ensure safety during the blowing-out process.
  3. Remove Pool Accessories: Take out ladders, handrails, and other removable items to avoid damage.
  4. Remove Drain Plugs: Ensure to remove drain plugs from the pool filter, pump, and heater.

 

Step-by-Step Guide to Blowing Out Pool Lines

  1. Attach the Blower to the System: Secure the blower to the skimmer or dedicated blower port using appropriate adapters. Ensure all valves are set to allow air flow.
  2. Blow Out the Skimmer: Start with the skimmer. Run the blower until only air is coming out, indicating all water is expelled. Watch for a steady stream of bubbles.
  3. Move to the Return Lines: Connect the blower to each return line sequentially. Plug each return line once air is coming out.
  4. Blow Out the Main Drain: Use the blower to clear the main drain. Continue blowing for 20-30 seconds after seeing a large plume of air to ensure no water remains.
  5. Check for Remaining Water: Verify no water remains in any lines by listening for changes in the blower's sound and observing the output. Repeat the process if necessary.

Skimmer

Connect the blower to the skimmer securely, ensuring it fits tightly to avoid air leaks. This connection is crucial for effective water expulsion. Once the blower is attached, turn it on and watch for water being expelled through the return jets. A consistent flow of water followed by a mist confirms that the skimmer line is clear. It’s essential to keep the blower running until only air is coming out, indicating all water has been removed​.

Return Lines

Move the blower to the return lines and secure it properly. Look for a steady stream of bubbles, which indicates that water is being forced out of the lines. Keep the blower running until only air is coming through, ensuring no water remains. This process may need to be repeated for each return line, so be systematic and patient to ensure complete water removal​.

Main Drain and Other Fixtures

Attach the blower to the main drain and other fixtures, such as pool cleaners and additional drains. Ensure all water is expelled by watching for bubbles and listening for a change in the blower's sound, which signals an empty line. The main drain can be more challenging due to its depth, so allow extra time for this process.

 

Sealing and Protecting Pool Lines

  1. Insert Winter Plugs: Place winter plugs in all lines to prevent water from re-entering.
  2. Add Antifreeze: Pour antifreeze into the lines for added protection against any remaining moisture.
  3. Check for Leaks: Ensure all plugs are secure and there are no leaks.
See our guide for more tips for winterizing your pool.

 

How To Blow Out Pool Lines - Frequently Asked Questions

  • What can I use if I don’t have a pool air blower? 

    You can use a shop vac or an air compressor with the appropriate fittings. However, an air compressor should be used carefully to avoid over-pressurizing the pipes.

  • How to identify if all water is expelled from the pool lines? 

    Look for a consistent flow of air bubbles from the return jets and other outlets. Only a fine mist should be visible at the end.

  • What should I do if water remains in the lines after attempting to blow them out? 

    Reattach the blower and ensure a tight fit, then continue blowing until all water is expelled.

  • How often should I check the winter plugs during the off-season? 

    Check the plugs at least once a month to ensure they remain secure and no water has entered the lines.

  • Are there any specific brands of antifreeze you recommend for pool lines? 

    Look for antifreeze specifically designed for pools, such as those offered by Royal Swimming Pools or other reputable brands.