How to Blow Out Sprinkler System with Air Compressor
Blowing out your sprinkler system with an air compressor is an effective way to winterize it and prevent any water from freezing and causing pipe damage. Here’s a step-by-step guide to help you accomplish this task safely and efficiently.
Step 1: Gather Your Tools and Equipment
Before starting, make sure you have:
- An air compressor with a cubic feet per minute (CFM) rating appropriate for your sprinkler system.
- An adapter to connect the air compressor to the sprinkler system.
- Safety goggles.
- Ear protection (optional).
Step 2: Shut off the Water Supply
Turn off the main water valve for your sprinkler system to stop the flow of water. This valve is often located in your basement, utility area, or near your water meter.
Step 3: Attach the Air Compressor
- Find the sprinkler system’s blow out port, which is typically located after the backflow device.
- Attach the air compressor hose to the blow out port using the appropriate adapter. Make sure the connection is secure to prevent disconnection once pressurized.
Step 4: Set the Air Compressor Pressure
- Adjust the air compressor to the recommended pressure levels (usually between 40-80 PSI, depending on the type of pipes you have).
- Overshooting the recommended pressure can damage your sprinkler system.
Step 5: Blow Out Each Zone Individually
- Start with the zone furthest from the compressor and work your way back to the nearest zone.
- Activate one zone at a time using the sprinkler system’s control box.
- Turn on the air compressor and let it run until you see only air, and no water, coming out of the sprinkler heads.
Step 6: Drain the Backflow Preventer
- Remove any water from the backflow preventer by turning the ball valves and test cocks to a 45-degree angle to allow any trapped water to escape.
Step 7: Unhook the Compressor and Seal the System
- Once all the zones are blown out, unhook the air compressor from the blow out port.
- Close the test cocks on the backflow preventer.
- If your system has a main valve to allow for air to escape (often a manual drain valve), make sure it’s closed.
Step 8: Turn off the Control Timer
- Although the water is shut off and the pipes are cleared, it’s generally recommended to also turn off your timer/controller.
Final Tips
- It’s a good idea to check the manufacturer’s guidelines because sprinkler systems can vary.
- If you’re not comfortable doing this yourself, consider hiring a professional to ensure it’s done correctly and to avoid potential damage to your system.
By following these steps, you will effectively blow out your sprinkler system, ensuring it stays in good shape through the cold season.