#equipment sizing

Tech Tips:

Equipment Sizing and Airflow in Different Markets

This tech tip was heavily informed by Ed Janowiak’s past symposium presentations. You can watch his presentation about setting proper airflow HERE. You can also now purchase your tickets for the 6th Annual HVACR Training Symposium HERE. HVAC School was founded by a Floridian—representing Climate Zone 2, to be exact. So, it’s no surprise that […]

Short Cycling

A friend of mine was telling me that a utility had the idea that they could reduce energy consumption by turning HVAC equipment on and off rapidly during times of high load. In their minds, wouldn't it be better to spread out the off time rather than keeping the system off for longer periods and […]

Reviving History: Upgrading an 80-Year-Old Steam Boiler in Portland, Maine

This tech tip was written by Jennifer Manzo. Thanks, Jennifer! As an HVAC technician in Maine, I've seen my fair share of aging systems, but nothing quite prepared me for the sight that greeted me while responding to a “no heat” call in a multi-family apartment building this winter. Stepping into the boiler room of […]

Size Matters — Industrial “Shortcomings”

This article was written by Jennifer Manzo, an HVAC technician and the founder of HVA-Chicks Coalition. You can find her on social media as @HVAChicksjennifer. Thanks, Jennifer! It’s no secret that the HVAC industry is in the throes of an oversizing epidemic. Instead of stating the obvious, I wanted to take a deep dive into […]

How to Properly Size a Dehumidifier

This tech tip was submitted to us by Tim De Stasio. You can read the original version on his website HERE. Tim will also be a panelist in the Dehumidification Hootenanny at the 2024 HVACR Training Symposium. Nikki Krueger will moderate, and Genry Garcia, Chris Hughes, and Chris Conway will be fellow panelists. If you’ve […]

Homeowner’s Guide to Sizing an AC System (and who is responsible when you’re uncomfortable)

This tech tip was a collaborative effort between Matt Bruner, Adam Mufich, Ed Janowiak, and Genry Garcia. Thank you to everybody who gave their input! The next time you come across a homeowner who wants a bigger HVAC system, or you simply want to set expectations for a customer, share this tech tip with them. […]

The Great Heat Pump Revolt of 2026 and How To Avoid It with Steve Rogers, Russ King and Chris Hughes

Q&A – Sizing Heat Pumps for Heat Load – Short #213

In this short Q&A podcast, Bryan answers a listener-submitted question about sizing heat pumps for heat load in heating mode, something that we haven't talked much about in the past due to the greater need for cooling in our market. In most cases across the country, a heat pump's heating loads will be greater […]

#Betterhvac: Taking the First Step… and the Second and Third

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Is Undersizing Really a Problem?

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Chris Hughes and Steve Rogers from The Energy Conservatory discuss TEC’s TrueFlow technology and its crucial role in predicting airflow issues in the sales process, particularly for heat pump retrofits. They explain how the TrueFlow app helps contractors accurately measure both static pressure and airflow in existing systems, enabling them to predict whether proposed equipment changes will work effectively. This is especially vital when considering the growing trend of replacing gas furnaces with heat pumps, as the airflow requirements can differ significantly.

The conversation delves into a detailed example of replacing an 80% efficient 48,000 BTU furnace with a heat pump. They demonstrate how the airflow requirement would nearly double from 652 CFM to 1,200 CFM, potentially causing the static pressure to quadruple due to Fan Law 2 principles. This dramatic increase could lead to significant performance issues if not properly addressed during the system design phase. The experts emphasize that using TrueFlow during the sales process allows contractors to identify potential problems and necessary modifications before installation rather than discovering issues during callbacks.

The discussion also covers the ideal workflow for system assessment and sales, starting with customer comfort evaluation and proper load calculations. It’s important to reduce loads through envelope improvements when possible, particularly in cold climates where heat pump retrofits are becoming more common. Proper system sizing often means going smaller rather than larger, contrary to common industry practices, and the worst HVAC systems are often found in expensive custom homes rather than tract housing.

Key Topics Covered:

TrueFlow technology and its role in system forecasting
Fan Law 2 and its impact on static pressure when changing airflow
Heat pump retrofit challenges and considerations
The importance of accurate load calculations
Dual fuel systems as a solution for cold climates
The relationship between airflow and static pressure
Sales process integration of technical measurements
Common issues with oversized equipment
The importance of envelope assessment
Methods for reducing system loads
Proper duct sizing and modification strategies
The role of proper filter sizing and selection
The benefits of flat-rate pricing for duct modifications
Training resources and support available for TrueFlow users

Check out TEC’s YouTube channel at https://www.youtube.com/@energyconservatory, and you can visit TEC’s website at https://energyconservatory.com/.

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