AC Systems Fail to Control Humidity and Comfort, Learn the Dehumidification Fix with Chris Howells

In this episode of the HVAC Know It All Podcast, host Gary McCreadie is joined by Chris Howells, Senior Training and Development Manager at AprilAire, to discuss the importance of dehumidification in indoor air quality and home comfort. Chris explains how air conditioners handle both temperature and moisture, and why many systems struggle to control humidity on their own. The conversation covers how standalone dehumidifiers work, including reheat and moisture removal, along with different installation methods and sizing considerations. Gary and Chris also explore common issues like oversized systems, seasonal humidity problems, and how proper humidity control can improve comfort, protect materials, and support overall health.

In this conversation, Chris explains the importance of dehumidification in HVAC systems and how it supports comfort, health, and home protection. He describes how air conditioners remove some moisture but often cannot control humidity on their own, especially in certain conditions. Chris and Gary discuss how standalone dehumidifiers work using cooling and reheat, along with different installation methods and sizing factors. They also cover how issues like oversized systems, seasonal moisture, and poor humidity control can lead to discomfort and reduced system performance.

Expect to Learn:

How dehumidification improves indoor air quality, comfort, and home protection.
How air conditioners handle moisture and why they often fall short.
How standalone dehumidifiers work using cooling and reheating.
How different installation methods affect system performance and airflow.
How issues like oversized systems and seasonal humidity impact comfort and efficiency.

Episode Highlights:

[00:00] - Sponsor Ad: Factory Direct Filters

[00:42] - Intro to Chris Howells

[02:36] - Listener problem: High humidity (55% RH) with an oversized AC

[04:14] - ACs prioritize sensible cooling; dehumidification is "leftover."

[06:01] - Chris mentions that Airflow verification is step one

[07:34] - How a dehumidifier works (reheat effect, no overcooling)

[10:47] - Installation methods: Return-to-return vs. fully ducted

[14:01] - 3 benefits of dehumidification: Health, comfort, home protection

[18:22] - Model E100 (100 pints/day) as a standalone example

[20:48] - Wet coil + dry supply air = humidification problem

[23:32] - Checking sensible/latent ratios at different wet-bulb temps