Commercial dehumidification is what separates a proper dry from a room that just smells damp for a week longer. The air movers get the water out of the carpet, plaster and timber. The dehumidifier is what takes that moisture out of the air so it doesn’t end up back in the building.
This guide is for restorers, carpet cleaners, builders and facility crews who need to pick the right class of machine for a water damage or mould job. It covers the three main types you’ll hear about (LGR, desiccant and conventional refrigerant), when a large dehumidifier actually makes sense, what a dehumidifier can and can’t do about mould, and when to buy versus hire.
It isn’t a drying protocol. Your moisture map, the materials, the insurer’s scope and the standard you work to still decide the setup. Treat this as the equipment side of the conversation.
What commercial dehumidification actually means
Commercial or industrial dehumidification just means removing moisture from air at a scale and duty cycle a household unit can’t handle. On a restoration job that means:
- running for days at a time, not a few hours
- still pulling water once the room is already drying and the air is less humid
- pumping condensate to a drain instead of filling a tank you empty every hour
- a body that can be wheeled, stacked and loaded into a van
The words get used loosely. “Commercial dehumidifier”, “industrial dehumidifier” and “restoration dehumidifier” often describe the same class of kit. What matters is the technology inside, the published water-removal figure and its test conditions, and whether the machine fits the space and the power you have.
The three types: conventional, LGR and desiccant
Conventional refrigerant dehumidifiers
A conventional refrigerant unit passes air over a cold coil. Moisture condenses on the coil and drains away. That’s the same principle as a household dehumidifier.
It works well when the air is warm and wet. The catch is what happens as the room dries. As the moisture content of the air drops, a conventional unit pulls less and less water. On day one it looks busy. On day three it’s often doing very little, right when you need it to finish the job.
Conventional units have a place for light-duty moisture control. They’re a poor fit for structural drying after a water loss.
LGR (low grain refrigerant) dehumidifiers
LGR stands for low grain refrigerant. “Grains” is a measure of how much water is in the air. An LGR dehumidifier is still a refrigerant machine, but it’s designed to keep removing moisture as the grains come down.
That’s why the LGR dehumidifier is the standard restoration dehumidifier. After extraction you’re not drying tropical air. You’re finishing a space that is already heading down, and you need a machine that keeps working there. The DryTrak Mini listing puts it simply: LGR technology is designed to continue removing moisture effectively as humidity levels reduce.
All three commercial dehumidifiers Restoration Warehouse currently lists are LGR units.
Desiccant dehumidifiers
A desiccant dehumidifier doesn’t rely on a cold coil. Air passes through a material (usually a rotating wheel) that absorbs moisture. A separate heated air stream dries the wheel out and carries that moisture outside, usually through ducting.
Because it isn’t condensing water on a coil, desiccant technology is generally chosen for cold spaces and for pulling air down to very low humidity, where refrigerant machines struggle. You’ll see desiccants on large commercial and industrial losses, cold buildings, some specialist timber-floor and contents work, and big-ticket jobs where an engineer is specifying the setup.
The trade-offs are real. Desiccant units usually need ducting to exhaust the wet air, they add heat to the space, and they’re a different setup from dropping an LGR in a closed room. If a job genuinely needs one, get the drying plan right before the machine turns up.
Restoration Warehouse doesn’t currently list a desiccant dehumidifier, so this section is for information only. If you think a job needs desiccant drying, talk to whoever is specifying the job.
Does a dehumidifier help with mould?
Yes, but only in one specific way. A dehumidifier helps with mould by bringing moisture down so conditions stop favouring growth and wet materials can dry. It does not kill mould, remove mould or clean a surface. Mould that has already grown still has to be dealt with under the remediation scope. That means containment, removal or cleaning, the right PPE and air filtration.
In practice, dehumidification shows up on mould jobs in two places:
- Drying the cause. If there’s been a leak or a flood, the building has to dry or the mould comes back. That’s structural drying: extraction, air movers and a dehumidifier sized to the space.
- Holding the space dry during and after remediation. Keeping humidity down in a contained area while the work is done and verified.
All three dehumidifiers below list mould remediation as a use or support use. Read that for what it is: a drying role, not a treatment. If the scope says mould, follow the scope and use a proper biocide, containment and air scrubber where they’re called for.
When a large dehumidifier makes sense
People search “large dehumidifier” and “largest dehumidifier” as if bigger is always better. On a restoration job, a large dehumidifier makes sense when:
- the affected area or volume is too big for a compact unit to keep up
- the water load is high (a lot of wet material, not just damp air)
- you’re drying a commercial space, basement or open-plan floor rather than a bathroom or hallway
It makes less sense when access is tight, the space is small, or power is limited. Two compact LGR units spread across two rooms often beat one big machine jammed in a doorway.
When you compare sizes, compare like with like. Water removal is published at a stated temperature and humidity. A “max” or “saturation” figure is taken at hot, wet conditions. An AHAM figure is taken at milder conditions (the usual AHAM point is 26.7°C / 80°F and 60% RH). A litre figure with no test conditions isn’t comparable at all. Check the drainage, the airflow and the electrical spec on the nameplate too, then add the dehumidifier to your circuit plan before the air movers.
Commercial dehumidifiers at Restoration Warehouse
Restoration Warehouse lists three LGR commercial dehumidifiers. They aren’t interchangeable. Choose on the listed water removal and its test point, the body, the drainage and the electrical spec.
DryTrak Mini Upright LGR Dehumidifier 50L
The DryTrak Mini Upright LGR Dehumidifier 50L is the compact upright. It lists AHAM water removal of 50 L/day at 30°C and 80% RH (a warmer, wetter test point than 26.7°C / 60%). It runs on 240 V at 750 W and 3.1 A, with 300 CFM process airflow. It has an integrated condensate pump with a continuous drain option, a digital display with real-time humidity monitoring and automatic defrost. Operating range is 5°C to 38°C and 20–90% RH. The rotomoulded housing has integrated wheels and a foldable handle. It’s the one for hallways, apartments and bathrooms where a bigger body won’t fit.
XPOWER XD-85LH LGR Dehumidifier
The XPOWER XD-85LH LGR Dehumidifier Commercial Low Grain Refrigerant Dehumidifier (model XD-85LH) lists water removal of 41 L (85 pints) per day at AHAM (27°C, 60% RH) and 69 L (145 pints) per day at saturation (32°C, 90% RH), with 306 m³/h airflow. It runs on 220–240 V / 50 Hz at 3.7 A. It has an auto purge pump with a 12.2 m drain hose, automatic speed control, a digital display for humidity and operating time, a dual intake system and a washable stainless steel filter, and it stacks up to three units high with wheels and a handle for moving around site. Listed operating range is 0.6°C to 40.6°C.
Dri-Eaz LGR Dehumidifier BD2500 230 Volt
The Dri-Eaz LGR Dehumidifier BD2500 230 Volt is the compact stackable. It lists 36 L/day AHAM at 26.7°C and 60% RH, and 63 L/day maximum at 32.2°C and 90% RH. It runs on 230 V at 3.4 A, with airflow of 272 m³/h maximum. It has automatic pump-out with a 12.2 m drain hose, a humidistat adjustable from 30 to 90%, a real-time inlet and outlet temperature and RH display, and remote monitoring capability. Listed dimensions are 32 × 46 × 55 cm and weight is 30 kg. Operating range is 1°C to 32°C. The listing describes it as fitting where larger dehumidifiers can’t.
Buy or hire?
If dehumidifiers are part of your core work, owning them usually makes more sense. You have the machine on the van the night the call comes in. If you only need extra capacity for a big job, or you’re a builder or facility manager with a one-off, hire is the simpler path.
Restoration Warehouse hires dehumidifiers out of Brisbane. See the Dehumidifier 2.0 hire and Large Commercial Dehumidifier 3.0 hire pages, or the full equipment hire range for air movers and air scrubbers to go with them.
Pair the dehumidifier with the right air movers, and count the circuit before you set up. For a deeper look at litres per day, amp draw and choosing between these three units, read how to choose a dehumidifier for restoration drying.
Get the right machine on the job
Most restoration and mould-related drying runs on LGR. Desiccant drying is a specialist call, and a conventional unit is for light-duty moisture control. Browse the current commercial dehumidifiers range, or talk to us about hire for the big jobs.
For current availability, the electrical spec or a site order, call 07 3568 4925, email sales@restorationwarehouse.com.au, or visit restorationwarehouse.com.au.
