Washing Commercial Coils and Water Challenges - Short #292 · HVAC School - For Techs, By Techs summary

Key takeaways

Clean coils improve HVAC system efficiency and longevity.
Use high flow, low pressure water (around 300-350 PSI) for effective coil rinsing.
Ensure adequate water access; recommend clients install plumbing if needed.
Prioritize safety by ensuring proper access to equipment before performing maintenance.
Follow a water-first approach: try water-only cleaning before using chemicals.
Dilute chemical cleaners properly to avoid damage and reduce rinse time.
Use portable and battery-powered water solutions in challenging environments.
Rinse coils from the inside out for best results.
Prepare for water and access challenges by including them in your contracts and planning accordingly.

Summary

Importance of Coil Cleaning and Water Management

This section discusses why coil cleaning is vital for HVAC system performance, referencing ongoing debates about its necessity. The host emphasizes that clean coils matter and shares field studies supporting this. Proper cleaning involves high flow, relatively low pressure water rinsing—around 300-350 PSI—using appropriate tools like portable battery-powered washers to adapt to water access challenges. The section highlights the importance of water access, safety considerations for technicians, and the need to incorporate water restrictions and access issues into maintenance contracts to ensure effective and safe coil cleaning.

Chemical Use and Protocols for Coil Cleaning

This part covers the significance of strict chemical policies, advocating for a water-first approach where possible. It recommends avoiding unnecessary chemical use and emphasizes proper dilution ratios to prevent coil damage through galvanic corrosion or vindragitation. The host discusses various methods of applying cleaner—bottom to top, letting it dwell, and rinsing from the inside out—and stresses the importance of minimizing chemical and water use for environmental and safety reasons. Techniques for mixing and applying the Venom packs and other cleaners are also explained in detail.

Water Access Solutions and Equipment for Coil Maintenance

This section explores practical solutions for water access issues during coil cleaning, especially in large commercial or multi-unit settings. It mentions using a ground-based water trailer with low-pressure output and battery-powered portable washers, like the DeWalt 20V MAX, which draw from portable water vessels such as five-gallon jugs. The host stresses the importance of having sufficient hoses, appropriate nozzles, and ensuring safe access to equipment, particularly on rooftops. Strategies for managing water supply challenges and the importance of proper contract language to account for additional labor due to water or access issues are discussed.

Practical Tips and Best Practices for Coil Cleaning

The final section provides actionable advice, including thorough pre-rinsing, proper application of cleaners, and rinsing from the inside out. It emphasizes the importance of safety, proper equipment, and effective water management. The host recommends maintaining a well-stocked truck with tools like brushes, towels, and plastic bags to handle debris and water runoff. Strategies for efficient cleaning—such as using portable water solutions and appropriate pressure settings—are explained with product recommendations like the DeWalt W550B. Overall, the emphasis is on safe, effective, and environmentally responsible coil cleaning procedures.

Show notes

In this short podcast episode, Bryan talks about considerations for washing commercial coils and water challenges techs might face. Despite being the topic of debate within the last several years, cleaning coils matters and will affect performance.

When washing coils, we use Refrigeration Technologies Viper cleaners (especially Venom Packs) when we actually need cleaners. No matter which cleaner you use (or if you don't), you want some pressure and a high flow rate when rinsing, but keep in mind that some pressure-washers may produce too much pressure and too little flow; the sweet spot is around 300 PSI, and microchannel coils require extra caution.

In terms of commercial maintenance contracts, we often have a lot of coils to wash and may not have adequate water access for the job. We find that the best move is to ask the client to install plumbing infrastructure that allows for better water access. If they refuse, you can increase the labor charge due to extra hose setups, reduced pressure, etc. The client must also be able to provide safe access to the coils; do not write a proposal or carry out a maintenance procedure if techs cannot carry out the work safely.

Strict chemical policies are important, too. Water-first approaches are best; if a water wash is sufficient, use just water and only escalate to chemicals if there is a clear need for a stronger cleaning. If you use chemical cleaners, use the proper dilution ratio; over-concentrated cleaners can damage coils. Chemicals also require more rinsing, and it's more economical to do as little rinsing as possible. Pre-rinsing, adding cleaner from bottom to top, letting the cleaner dwell, and rinsing off is the ideal sequence.

If you encounter water challenges on the ground, you can use a ground-based water trailer with a high-output, low-pressure washer attached. If the issue is on the roof, a battery-powered washer can help (like the Dewalt 20V MAX cordless power cleaner); they draw from vessels of water, like 5-gallon jerricans. Remove the casing if you need to (making sure the client pays for that additional labor), and rinse from the inside out.

Learn more about Refrigeration Technologies cleaners at https://www.refrigtech.com/.

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Washing Commercial Coils and Water Challenges - Short #292