how big compressor to blow out sprinklers

3 min read 06-02-2025

how big compressor to blow out sprinklers

Protecting your sprinkler system from winter damage is crucial. Blowing out your sprinkler lines with compressed air is a common and effective method. But choosing the right compressor size is key to a successful and safe blowout. This article will guide you through determining the appropriate compressor size for your sprinkler system.

Understanding Your Sprinkler System

Before selecting a compressor, you need to understand your system's size and complexity. Key factors include:

Pipe Length and Diameter: Longer and larger diameter pipes require more air volume to effectively clear water.
Number of Zones: Multiple zones mean more lines to clear, increasing the overall time and air demand.
Pipe Material: Different materials might have varying levels of resistance to airflow.
Elevation Changes: Systems with significant elevation changes require more powerful compressors to overcome gravity.

Assessing Your System's Air Demand:

Accurately determining your system's air requirements can be challenging without specialized equipment. However, here's a simplified approach:

Small Systems (under 10 zones, relatively short pipe runs): A smaller, portable compressor (5-7 CFM at 90 PSI) might suffice. These are typically suitable for residential systems with minimal complexity.
Medium Systems (10-20 zones, moderate pipe runs): You'll likely need a mid-sized compressor (7-10 CFM at 90 PSI or higher).
Large Systems (over 20 zones, extensive pipe runs): A large, stationary compressor (10+ CFM at 90 PSI or higher) will be necessary.

Compressor Specs to Consider

Beyond CFM (Cubic Feet per Minute), several other compressor specifications are crucial:

Pressure (PSI): Aim for at least 90 PSI. This ensures sufficient force to push water out of the lines.
Tank Size: A larger tank helps maintain consistent pressure during the blowing process, preventing the compressor from cycling too frequently.
Duty Cycle: This indicates the percentage of time the compressor can run without overheating. A higher duty cycle is essential for longer blowout jobs.
Horsepower (HP): Higher horsepower generally translates to greater capacity, though CFM is a more reliable indicator of blowing power.

Important Note: Always consult the manufacturer's specifications for your specific compressor model to understand its capabilities and limitations.

Choosing the Right Compressor: A Step-by-Step Guide

Assess Your System: Carefully evaluate your sprinkler system's size, complexity, and pipe specifications.
Estimate Air Demand: Use the guidelines above as a starting point. Remember, it's better to overestimate than underestimate.
Consider Compressor Specs: Select a compressor with sufficient CFM, pressure, tank size, and duty cycle.
Consult Professionals: If you're unsure, seek advice from a sprinkler system professional or a compressor specialist. They can help you accurately determine the appropriate size.

Safety Precautions:

Never attempt to blow out your sprinkler system without first turning off the water supply.
Ensure adequate ventilation when using a compressor. Exhaust fumes can be dangerous in enclosed spaces.
Wear appropriate safety glasses and hearing protection.
Use caution around moving parts.
Inspect all connections before starting.

Frequently Asked Questions (FAQs)

Q: Can I use a smaller compressor than recommended?

A: While you might be able to use a smaller compressor for a very small system, it's likely to be inefficient and may not completely clear the lines. This can lead to freezing and damage during winter.

Q: What happens if I use a compressor that's too small?

A: You risk incomplete water removal, leading to frozen and burst pipes.

Q: What if I have a very large, complex system?

A: For larger systems, consider hiring a professional irrigation service. They possess the necessary equipment and expertise for a safe and effective blowout.

By carefully considering your system's needs and the compressor's specifications, you can ensure a successful sprinkler system blowout and protect your investment from winter damage. Remember safety first!