2026-01-26 – Weekly HVAC News : First-year apprentice skills

Last week, our HVAC community engaged in a series of thoughtful discussions spanning technical insights and professional development. Members explored the origins and applications of the 400 cfm per ton rule, debated the essential skills for first-year apprentices, and shared strategies for optimizing energy efficiency in HVAC systems. Conversations also delved into the latest in continuing education opportunities and practical tips for quality installations.


This Week’s Hot Topics

Origin of the 400 cfm per ton rule
This thread unpacks the historical and practical reasons behind the 400 cfm per ton standard. It’s a must-read for anyone looking to understand the fundamentals of system design.
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First-year apprentice — what to master next
New to the trade? Seasoned pros offer their take on the skills that will set you up for success in your first year.
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Not a salt shaker, it’s 404A
A light-hearted yet informative discussion about the intricacies of handling refrigerant 404A.
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Worthwhile CEUs for CO2 and EEVs
Explore the continuing education units (CEUs) that are truly beneficial when working with CO2 systems and electronic expansion valves (EEVs).
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CE that actually cuts kWh/ton
A deep dive into continuing education courses that promise real energy savings.
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Day-one habits for quality installs
Discover the essential habits for ensuring quality installations from the get-go.
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Fill pressure on three-story hydronic systems
Join the discussion on the right fill pressures for complex hydronic systems.
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Verifying VAV airflow after sensor swap
Tips and tricks for confirming VAV airflow accuracy after replacing sensors.
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Where new techs stumble on big systems
Identify common pitfalls that new technicians face when working on large HVAC systems.
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Which contract clause saves the most
Explore contract clauses that could potentially save time and money.
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Thanks for engaging with the community and taking the time to stay informed. Looking forward to more insightful discussions next week.

1 Like

I have first-year apprentices measure total external static on every tune-up with a $40 digital manometer and write it on the furnace door; it’s the fastest way to tell if that ‘400 cfm per ton’ target is happening. The rule’s fine, but I keep finding the return or filter is the bottleneck, so we teach them to check that first before chasing charge or controls.

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