LGR vs. Desiccant vs. Refrigerant Dehumidifiers: Which One Dries Your Phoenix Home?

📅 2026 🏷 Structural Drying ⏱ 5 min read

Dehumidification is half of every structural drying plan, and the type of unit used has a direct effect on how quickly a drying chamber reaches target humidity.

Refrigerant Dehumidifiers: The Everyday Workhorse

Refrigerant dehumidifiers pull air across a cold coil, condensing moisture out as the air cools below its dew point. They perform well in warmer, more humid conditions, which makes them a common choice for standard residential drying in moderate ambient conditions. If cost is on your mind, how our pricing works breaks down what typically drives the number up or down.

Low Grain Refrigerant (LGR) Units

Structural Drying Equipment Setup illustration — Structural Drying Equipment Setup

LGR dehumidifiers add a secondary cooling stage that lets them continue extracting moisture effectively even as the air in the drying chamber becomes progressively drier — something standard refrigerant units struggle with. Because Phoenix's climate often starts with low ambient humidity to begin with, LGR units are frequently the default choice for reaching aggressive target moisture levels efficiently. We've answered a lot of related questions on answers to common questions.

Desiccant Dehumidifiers for Cold or Deep-Set Moisture

Desiccant units use a chemical drying agent instead of refrigeration, which lets them perform in colder conditions where refrigerant units lose efficiency — relevant for crawl spaces or unconditioned areas. They're also commonly used for specialty applications like wall cavity drying through ducted hoses, where moisture needs to be pulled from deep inside a structural assembly. For background from an independent source, see the IICRC S500 restoration standard.

How Crews Decide Which Type to Deploy

Drying Equipment Facts illustration — Drying Equipment Facts

The decision comes down to the temperature and starting humidity of the drying chamber, the materials involved, and whether the space is conditioned or not. It's common for a single job to use a combination — LGR units in the main living space and a desiccant unit ducted into a crawl space or wall cavity simultaneously. the EPA's moisture control guidance has useful guidance on this if you want to read further.

Sizing Dehumidification Capacity to the Job

Dehumidifier capacity is measured in pints of water removed per day and is calculated against the cubic footage of the drying chamber and the class of water damage, similar to how air mover count is calculated. Under-sizing dehumidification capacity is one of the most common reasons a drying program stalls despite adequate airflow. You can also review the Department of Energy's ventilation and humidity guidance for an outside perspective on this.

Frequently Asked Questions

Crawl spaces and other unconditioned or hard-to-reach areas often call for a desiccant dehumidifier, which performs better in cooler conditions and can be ducted into confined spaces more easily than a standard refrigerant unit.

LGR units are generally more effective at continuing to pull moisture as air gets drier, which is valuable in the later stages of a drying program, but they aren't strictly 'better' in every scenario — the right choice depends on conditions in the drying chamber.

That's expected, and actually a good sign — it means the unit is actively pulling moisture out of the air that evaporated from your wet materials. Most restoration-grade units drain continuously via a hose rather than requiring manual bucket emptying.

Not necessarily. The drying chamber itself often runs at elevated humidity due to active evaporation from wet materials, regardless of outdoor conditions, so dehumidification capacity is still calculated based on chamber conditions rather than outdoor climate alone.

Opening windows introduces uncontrolled, variable humidity into the drying chamber and defeats the calculated balance between air movement and moisture removal, which is why professional drying programs keep the chamber sealed rather than relying on outdoor air exchange.