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Acid and Contaminants Testing w/ John Pastorello

By John Pastorello Bryan Orr

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John Pastorello from Refrigeration Technologies joins us to talk about testing oil and refrigerant for contamination. He also explains what each test is good for. John developed the Checkmate testing kit when he recognized a need to test reclaimed and recycled R-12 for acid and moisture.

The Checkmate method removed a small amount of refrigerant from the system for testing. The Checkmate apparatus hooks up to a refrigeration system to test the oil. You insert a tube with a rubber stopper, and you can draw refrigerant from the system when the tool pierces the rubber stopper; the method is similar to drawing blood. The kit then assesses the acid content in the refrigerant and creates a colored stain that indicates the acid content. You can use an included color chart to interpret the stain color.

Checkmate also assesses oil based on its dielectric strength; contaminants can give oil conductive properties, which the test picks up on. Unfortunately, oil breakdown can happen even when technicians use best practices, and it’s commonplace on aging systems. Some tests only pick up on acid, not moisture. However, Checkmate picks up on the moisture content as well, which can be an indicator of future acid problems.

Many technicians don’t perform oil testing frequently enough; if they test the refrigerant or oil at all, it’s only infrequently, such as during PMs. More frequent testing could occur with easier testing methods, such as by using the Checkmate kit, and it could save HVAC system owners lots of money in the long run.

John and Bryan also discuss:

Diagnosing compressor burnout
Conductive oil
Gradual oil breakdown
Schrader core testing devices
PVE oil
Air and moisture skewing other test methods
Vapor testing
Venting exemptions for acid/moisture testing (de minimis)
Checkmate tube shelf life
Suction driers

Learn more about Refrigeration Technologies HERE.

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Author:

John Pastorello

Bryan Orr

Company: Kalos Services

Position: Co-Founder and President

Check out our most recent video

How to Evacuate an AC system, Full Vacuum Procedure

Our latest Podcast

HVAC School – For Techs, By Techs

Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.

In this episode of the HVAC School Podcast, Bryan sits down with Chris Howells, senior training manager at AprilAire, to talk about what really makes a filtration system perform. Chris has nearly thirty years in the industry, including fifteen as a technician, and brings a field-first perspective on why filtration is more than just “a filter.” Bryan also admits up front that his own contracting company is looking to put more high-efficiency filters into the field, so this conversation doubles as a practical learning session.

The discussion starts with a common misconception: that a “thicker” filter is simply a filter with thicker media. Chris explains that what matters is surface area, face velocity, and pressure drop, not the width of the cabinet. They cover why using the full face of the filter is one of the easiest wins, how a poorly designed return can load just one section of the media, and why a high MERV rating does not automatically mean high resistance. Cabinet design, media construction, and overall system design all play a role, and modern ECM blowers make low static pressure more important than ever.

From there, the conversation turns to bypass air and measurement. Chris describes how AprilAire’s cabinets use top and bottom rails and a self-seal media overhang to force air through the filter, backed by a 10-year clean coil guarantee. He and Bryan stress using the right tools, including a dual-port manometer and a proper static pressure probe, and checking pre-filter and post-filter pressure drop against manufacturer performance data at around 500 feet per minute. Chris also debunks the idea that deeper media is always more restrictive, pointing out that a typical retail one-inch pleated filter can raise pressure drop dramatically compared with a basic fiberglass filter.

The final stretch is about communication and growth. Chris and Bryan share simple, natural questions technicians can use to start air quality conversations without sounding like a sales pitch, and they encourage listeners to stay curious and keep asking “why.” Chris closes with resources for learning more, including AprilAirPartners.com and the AprilAire Academy, and mentions that the Santa Fe and UltraAire product lines are now part of the AprilAire family.

Topics Covered

Why “thicker” filters are really about surface area, face velocity, and pressure drop
Using the full face of the filter and avoiding uneven loading
How filters affect blower performance, system capacity, and equipment protection
Why filtration is a high-value upgrade compared with bulbs and modules
AprilAire’s new high-efficiency product line and its three-layer media design
Reducing bypass air with rail design, self-sealing media, and the 10-year clean coil guarantee
Measuring static pressure correctly and using manufacturer pressure drop charts
Sizing media cabinets by CFM and face velocity instead of what fits under the air handler
Common myths about MERV ratings and restriction
Conversation starters that help technicians talk about indoor air quality
How to learn more through AprilAirePartners.com, the AprilAire Academy, and local distributors

This episode contains embedded sponsor messages from Refrigeration Technologies, Carrier, Copeland, Santa Fe Dehumidifiers, and TruTech Tools.

Resources

Purchase your tickets or learn more about the 8th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

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