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Dehumidification Facts w/ Nikki

By Nikki Krueger Bryan Orr

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In today’s podcast, Nikki and Bryan discuss dehumidification. They cover the relationship between cooling and dehumidification, humidity control, and dehumidifier installation practices.

If the A/C unit is the king, the dehumidifier is the queen. The A/C unit controls cooling and humidity, but it can only do so much. A dehumidifier helps the A/C manage comfort under more demanding conditions. Many factors contribute to comfort, including sensible heat ratio (SHR), relative humidity (RH), and ventilation. Dehumidification reaches all of those factors.

Humidity control requires a holistic approach. Band-aid fixes DO NOT work. Dehumidifiers should work with the A/C system and building design to keep RH in the 50-55% range. Proper installation is vital. For example, tying into the HVAC supply is a recommended practice. Returns are the opposite; dedicated returns are preferred. Other factors to consider are proper sizing, Manual J, and customer expectations.

Join Nikki and Bryan as they cover:

Relative humidity targets
Sensible heat ratio (SHR)
Latent removal capacity
Ventilation
Building design and tightness
Manual J
Challenges with ductless systems
Ducting into the supply with dedicated returns
Installation practices
Dehumidifier sales and customer service

And much more…

To learn more about Santa Fe Ultra series, go to www.santa-fe-products.com. You can scroll through the products to find the Ultra series free-standing ventilating dehumidifiers.

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Author:

Nikki Krueger

Company: Santa Fe Indoor Air Quality Solutions

Position: Director of Marketing & Business Development

Bryan Orr

Company: Kalos Services

Position: Co-Founder and President

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Topics Covered

What a glycol secondary loop system is, and how it differs from direct expansion
Why retrofits are happening: refrigerant charge reduction, safety, EPA regulation, and zero-emissions goals
Efficiency penalties at small scale, and why efficiency isn’t the driver
How glycol behaves in the coil: no latent exchange, a temperature gradient, and frost patterns
Reliability trade-offs: simple case controls versus centralized, mission-critical valves
Staging a retrofit so the store stays open, including pre-piping, pre-testing, and pipe cleaning
Brazing versus soft solder, and whether nitrogen flow matters with glycol
Skid components: heat exchanger, VFD pumps, air separator, feeder tank, expansion tank, strainers, and suction guide
Controller inputs, EEV drivers, and emergency mobile chiller connections
Balance valves (automatic versus manual) and defrost methods, including off-time and electric
Fluid distribution: pitching pipe for air and drainage, plus vents and drains
Propylene versus ethylene glycol, the 35% mix, freeze point, and why more glycol hurts heat transfer
CO2 as a secondary fluid for low-temperature applications
Commissioning steps: electrical checks, pressure testing, filling, purging, and testing valve operation
Proving performance: flow, glycol concentration, temperature, and superheat on the rack side
Troubleshooting air in the system and pressure changes as glycol chills
Store humidity, dew point targets, and case performance
Heat reclaim using glycol loops
Tools: PT ports, manometers, female-to-female hoses, refractometer, and transfer pumps
Service tips: distilled water, matching glycol brands, and glycol safety