LGR Dehumidifiers: Low-Grain Refrigerant Capacity & Selection

LGR means low-grain refrigerant. The term matters in restoration because drying conditions change as a job progresses: air that starts warm and very wet can become much drier, and a useful restoration dehumidifier needs to keep removing moisture as the vapor load falls. This page owns the LGR technology/product-class intent rather than the broader commercial-dehumidifier shopping intent.

What “low grain” means in practical restoration terms

As moisture is removed from the air, the humidity ratio—or grains of moisture per pound of dry air—falls. A low-grain refrigerant dehumidifier is engineered to maintain useful refrigerant drying performance deeper into those drier conditions than a conventional refrigerant unit typically would.

Manufacturers implement that goal differently. Dri-Eaz describes technologies such as Extreme Dewpoint Technology and Advanced Crossflow Technology on current LGR lines. Phoenix traces its LGR line back to the Phoenix 200 and emphasizes low-grain operation across several current models. The site therefore treats “LGR” as a documented product class rather than inventing one universal internal design formula.

AHAM and saturation ratings still need to stay separate

LGR does not make test conditions irrelevant. A current Dri-Eaz LGR 7000XLi publishes 130 PPD at AHAM conditions and 235 PPD at saturation. AlorAir Storm LGR 850X publishes 85 PPD AHAM and 180 PPD saturation. Those figures describe different environmental conditions.

A buyer comparing LGR models should use the AHAM field when a common-condition comparison is needed, then use saturation and other published low-grain information as separate context.

Current LGR comparison points

Current modelAHAMSaturationProcess airAmpsWeight
Dri-Eaz Revolution LGR80 PPD144 PPD180 CFM5.5 A63 lb
Dri-Eaz LGR 5000Li80 PPD164 PPD215 CFM5.1 A69 lb
AlorAir Storm LGR 850X85 PPD180 PPD210 CFM5.9 A63 lb
Dri-Eaz LGR 6000Li100 PPD219 PPD320 CFM6.5 A99 lb
AlorAir Storm LGR 1250X125 PPD264 PPD300 CFM8.1 A79.2 lb
Dri-Eaz LGR 7000XLi130 PPD235 PPD280 CFM8.8 A106 lb
Phoenix DryMAX XL Pro135 PPDN/A in current normalized record300 CFM6.7 A85 lb
Phoenix 250 MAX145 PPDN/A in current normalized record365 CFM8.2 A119 lb

Compact LGR and high-capacity LGR solve different fleet problems

Dri-Eaz Revolution LGR and AlorAir Storm LGR 850X are roughly 63 lb in the current catalog, while larger machines such as LGR 7000XLi and Phoenix 250 MAX exceed 100 lb. A compact machine can be much easier to move up stairs and distribute across several areas. A larger machine can reduce the number of units needed for a high moisture load.

That is why Restoration Select will not create a single “best LGR dehumidifier” ranking based on AHAM alone.

Process air is not the same as moisture-removal capacity

Dri-Eaz LGR 6000Li publishes 320 CFM and 100 AHAM PPD, while LGR 7000XLi publishes 280 CFM and 130 AHAM PPD. The lower process-air figure does not prevent the 7000XLi from publishing higher AHAM moisture removal.

Process airflow can matter for ducting and distribution, but LGR capacity must be evaluated as its own field.

Why LGR performance becomes more important later in a drying cycle

Early in a very wet loss, the air can contain a large amount of moisture and many refrigerant dehumidifiers can remove water rapidly. As the environment dries, the remaining moisture is harder to remove from the air and materials. LGR equipment is designed for that lower-grain part of the process, where maintaining useful vapor-pressure reduction becomes more important than simply posting a large saturation number.

This is also why one headline PPD figure cannot describe an entire drying curve. A machine may perform very strongly at saturation yet differ from another unit as temperature and humidity fall. Restoration Select therefore keeps the product class, AHAM capacity, saturation capacity, process air and manufacturer-specific low-grain technology claims as separate evidence rather than calculating an undocumented “late-stage drying score.”

Compare the whole LGR platform, not only the refrigeration label

Two LGR models can share the same basic technology category and still have very different field workflows. Compact machines may fit bathrooms, kitchens and stairs more easily; larger units can reduce equipment quantity on open losses; high-temperature models can remain usable in hotter structures; connected models can support remote condition tracking.

For a contractor standardizing a fleet, filter availability, pump service access, hose/cord storage, stacking, ducting and control familiarity can matter as much as a small capacity difference. Those factors belong in future Finder and Compare logic only when the exact manufacturer evidence is available.

Energy efficiency deserves its own field

Some manufacturers publish COP in liters per kilowatt-hour. Current AlorAir records include 2.44 L/kWh for Storm LGR Extreme, 2.5 for Storm LGR 850X and 2.66 for Storm LGR 1250X. Phoenix also markets energy efficiency as a major design goal on its LGR line.

COP should be compared only when the manufacturer publishes the metric on a sufficiently compatible basis. Restoration Select does not calculate missing COP values from incomplete marketing data.

Operating temperature can separate otherwise similar LGR units

Current Phoenix 250 MAX documentation publishes operation from 33°F to 125°F, which is notably broader at the hot end than many compact LGR units. AlorAir Storm LGR 850X publishes 33.8°F–110°F, while Storm LGR Extreme publishes 33.8°F–104°F.

Those limits can matter on hot restoration jobs, unconditioned structures and cool basements. They should be taken from the exact current model, not borrowed from a related series.

Pump drainage and monitoring are workflow features

Many LGR machines are intended to run for long periods. Built-in pumps reduce the need for manual water collection. Connected platforms from Dri-Eaz, AlorAir and Phoenix can add remote visibility or asset tracking. Those features can change labor and jobsite workflow even when the moisture-removal capacity is similar.

LGR does not determine how many units a water loss needs

A technology label cannot replace a drying plan. The number of LGR dehumidifiers needed depends on the affected materials, moisture load, environmental conditions and professional procedure. Restoration Select keeps the future water-damage sizing tool evidence-gated for that reason.

For the restoration-workflow intent, use Water Damage Dehumidifier.

Current LGR shopping paths

The strongest current Amazon-verified LGR routes in the normalized catalog are selected AlorAir models. They do not define the editorial universe; Dri-Eaz and Phoenix models remain central comparison points even when no safe exact Amazon route is active.

Related dehumidifier decisions

Use the page that matches the decision you are actually making. These pages intentionally separate broad commercial selection, restoration drying, LGR technology, heavy-duty industrial use and basement moisture control.

Primary references for this page

Use the live dehumidifier tools

Dehumidifier Finder Compare Dehumidifiers Water Damage Capacity Planner

Compare current Dri-Eaz LGR models

See AHAM, saturation, process-air, amp, weight and filter differences across the Dri-Eaz models currently normalized by Restoration Select.

Dri-Eaz Dehumidifiers LGR 7000XLi details

Compare AlorAir Storm LGR models

See the normalized AlorAir LGR capacity, process-air, amp, weight and operating-range differences.

AlorAir Commercial Dehumidifiers Storm LGR Extreme

Frequently asked questions

What does LGR mean on a dehumidifier?

LGR means low-grain refrigerant. In restoration equipment, the term is used for refrigerant dehumidifiers engineered to continue removing moisture efficiently as air becomes drier and vapor pressure falls.

Is every commercial dehumidifier an LGR dehumidifier?

No. Commercial describes intended duty/use; LGR describes a particular refrigerant drying approach or product class. Many restoration dehumidifiers are LGR, but the terms are not interchangeable.

Is saturation PPD the best way to compare LGR dehumidifiers?

No. Keep saturation and AHAM ratings separate. For cross-model comparison, AHAM capacity at a common test condition is often more useful when available.

Does higher process airflow mean better low-grain performance?

Not by itself. Process air and moisture-removal capacity are separate fields. Low-grain performance depends on the refrigeration system and operating conditions, not just fan CFM.

Why do LGR dehumidifiers have pumps?

Many restoration LGR units are designed to run continuously, so a condensate pump makes drainage practical when gravity drainage is not available.

Are LGR dehumidifiers useful outside water damage restoration?

Yes. Manufacturers also position them for construction drying, humidity control, basements, crawlspaces and other commercial applications, but the exact fit depends on operating range, drainage, sound and installation needs.