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#reheat dehumidification

Tech Tips:

Set Inverter Technology Up for Success in Humid Climates

This tech tip about humidity control, particularly as it relates to VRF systems and others that use inverter technology, is a companion piece to a podcast episode with Roman Baugh. You can listen to that podcast episode HERE. Those of you who work in humid climates and install or repair ductless systems are probably well […]

Bypass Dehumidification/Airflow HVAC Design

There have been several past posts on our Facebook group page about a concept called bypass dehumidification. I think technicians could benefit from learning more about this topic. Bypass dehumidification or airflow is an interesting method for utilizing mixed air temperatures to maximize a system’s dehumidification capabilities. It's also a means of supplying adequate air […]

VRF, Ductless and Humidity Control w/ Roman

In this comprehensive episode, Bryan and Roman dive deep into one of the most challenging topics in modern HVAC: making VRF (Variable Refrigerant Flow) and ductless systems perform effectively in humid climates like Florida. The conversation tackles a common misconception that inverter-driven equipment automatically handles humidity well simply because it can “turn down.” Roman […]

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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 comprehensive training session from the symposium, Tony Gonzalez, Training Director at Fieldpiece, delivers an engaging and practical guide to combustion analysis for HVAC technicians. With 25 years of experience at Fieldpiece—from warehouse worker to training director—Tony brings both technical expertise and real-world application to this 50-minute interactive session focused on the company’s CAT 85 combustion analyzer.

Tony emphasizes that combustion analysis serves four critical purposes: safety, efficiency, equipment specification verification, and liability protection. He makes a compelling business case for investing in combustion analyzers, noting that preventing just two callbacks or one liability lawsuit can pay for the equipment ten times over. The training walks attendees through the complete process, from properly warming up the analyzer in fresh air (allowing sensors to calibrate to ambient oxygen and zero carbon monoxide) to generating professional PDF reports that can be shared with customers or integrated into work order management systems like ServiceTitan.

The session provides detailed guidance on interpreting key measurements, including stack temperature, oxygen percentage, carbon monoxide levels, and draft pressure. Using design parameters from the National Comfort Institute, Tony demonstrates how to diagnose issues by comparing actual readings against acceptable ranges for different furnace types (atmospheric, 80% induced fan, and 90+ percent condensing). He walks through practical troubleshooting scenarios, showing how measurements like high oxygen combined with low stack temperature can point to specific problems like low gas pressure that technicians can then verify and correct.

Throughout the presentation, Tony emphasizes proper technique and best practices, from creating test ports at least 12 inches above the inducer fan to the importance of plugging test ports after completion. He also highlights innovative features of Fieldpiece’s analyzers, including the hydro cycle pump that eliminates traditional water traps, sensor vault technology that extends sensor life to four years, and built-in wireless connectivity allowing technicians to view measurements on their mobile devices through the Job Link app.

Topics Covered:

Why perform combustion analysis: Safety verification, efficiency optimization, OEM specification compliance, and liability protection
Business benefits: Reducing callbacks, improving OEM relationships, enhancing professional image, and protecting against lawsuits
Proper startup procedure: Warming up analyzers in fresh air for accurate oxygen and CO sensor calibration
Ambient CO testing: Using combustion analyzers vs. dedicated walk-around detectors for carbon monoxide detection in living spaces
Test port installation: Proper placement at least 12 inches above inducer fans and away from 90-degree elbows
Key measurements explained: Stack temperature, oxygen percentage, CO PPM, CO air-free, draft pressure, and efficiency calculations
Equipment type selection: Choosing correct settings for atmospheric, 80% induced fan, or 90+ percent condensing furnaces
Diagnostic interpretation: Using National Comfort Institute parameters to identify issues like excess combustion air or low gas pressure
Advanced features: Built-in dual port manometer for gas and static pressure, wireless Job Link app connectivity, and hydro cycle pump technology
Report generation: Creating professional PDF reports with company branding for customer documentation and CYA protection
Maintenance tips: Checking particle filters, understanding sensor vault technology, and the importance of annual calibration
Sensor longevity: Four-year sensor life warranty and field-replaceable sensors without sending equipment for service

Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.

Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

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Search Episodes

Combustion Analysis w/ Tony G.

12/25/2025

Bryan Orr

Give Until it Hertz – The Battle Over Frequency – Short #271

12/23/2025

Bryan Orr