Most commercial laundries run too humid because operators treat ventilation as a complete solution.
Washers, ironers, flatwork folders, and tumble dryers push thousands of litres of moisture into the air each week. Ventilation alone shifts hot, wet air outside but does nothing to control the humidity that remains in the building.
A refrigerant dehumidifier paired with good airflow solves the problem at the source. This article covers why refrigerant units suit commercial laundries, how to size them properly, and the maintenance that keeps them running for years.
Need help sizing a unit? Browse the full range of commercial dehumidifiers or read about refrigerant dehumidifiers specifically.
Why Commercial Laundries Have a Humidity Problem
Every piece of equipment in a commercial laundry adds moisture to the air. Washers release steam during spin cycles, tunnel finishers push heated vapour into the room, and even condensing dryers vent residual humidity.
A mid-sized laundry processing 500 kg of linen per shift can add 200+ litres of water vapour to indoor air daily. The result is relative humidity that regularly exceeds 70%, forming condensation on cold surfaces like steel frames and ceiling panels.
Left unmanaged, that condensation causes real damage:
- Corrosion on machine housings, conveyors, and electrical panels
- Mould growth on walls, ceilings, and stored linen
- Slip hazards from wet floors under condensation drip points
- Linen quality issues where items come out of the press damp or develop musty odours
- Electrical faults from moisture ingress into switchboards and control panels
Australian Standard AS 1668.2 sets minimum extraction rates for commercial laundries (40 L/s per non-condensing dryer). But extraction only moves air out. It does not control the relative humidity of the air that stays inside the building.
How Refrigerant Dehumidifiers Work in Hot, Wet Spaces
A refrigerant dehumidifier pulls room air across a cold evaporator coil. The temperature drop forces moisture in the air to condense on the coil surface, the same way water beads on a cold glass.
That condensate drains into a collection tray and pumps to a floor drain. The now-dry air passes over a warm condenser coil, reheating slightly before returning to the room.
This cycle runs continuously. A built-in humidistat measures room humidity and cycles the compressor to maintain a target range, typically 45–55% RH for commercial laundries.
| Factor | Refrigerant Dehumidifier | Desiccant Dehumidifier |
|---|---|---|
| Best operating temperature | Above 20°C | Any temperature (works below 0°C) |
| Energy consumption | Lower at warm temps | Higher overall |
| Moisture removal rate | High in warm, humid air | Consistent across conditions |
| Maintenance complexity | Moderate (filters, coils) | Higher (rotor replacement) |
| Upfront cost | Generally lower | Generally higher |
| Ideal laundry fit | Standard commercial laundries | Cold-room or unheated facilities |
Commercial laundries almost never drop below 20°C during operating hours. Washers and dryers generate constant heat, keeping ambient temperatures between 25°C and 40°C, which is exactly where refrigerant dehumidifiers perform best.
Sizing a Refrigerant Dehumidifier for Laundry Operations
Under-sizing is the most common mistake in commercial laundry dehumidification. Operators buy a unit rated for the room’s square metreage and forget that laundry equipment generates moisture far beyond what an empty room would produce.
Start with the moisture load, not the floor area. Each kilogram of linen absorbs roughly 1.5 to 2 litres of water during washing, and a percentage of that water ends up as vapour in the room rather than going down the drain or out the exhaust.
A practical sizing approach:
- Calculate daily linen throughput in kilograms (e.g. 800 kg/shift)
- Estimate residual moisture entering the room as vapour, typically 10–20% of total water used depending on dryer exhaust quality
- Convert to litres per day of moisture the dehumidifier must remove
- Add a 30% buffer because rated extraction capacity drops 30–50% in real-world conditions compared to lab ratings
- Check the unit’s performance curve at your actual operating temperature and humidity, not just the headline rating
A laundry processing 800 kg of linen daily might need to remove 80 to 120 litres of moisture from the room air. That calls for one or more commercial-grade units with a combined rated capacity well above that figure.
Moisture Cure Commercial provides sizing guidance for every unit in the refrigerant range, and the team can run load calculations for your specific facility.
Where to Position Dehumidifiers in a Laundry Facility
Placement matters almost as much as capacity. A correctly sized unit in the wrong spot will struggle to reach target humidity levels.
The goal is to intercept moisture-laden air before it reaches surfaces where condensation causes problems. Position units near the primary moisture sources: wash lines, ironers, and folder discharge areas.
Key placement principles:
- Mount at ceiling height where hot, humid air naturally rises and collects
- Face the intake toward the wash line or ironer bank where steam generation peaks
- Direct the dry air outlet toward storage areas and linen handling zones
- Avoid placing units directly above electrical panels where condensate leaks could cause damage
- Keep a minimum 500 mm clearance around all sides for airflow and filter access
For larger laundries (over 300 m²), a single unit rarely covers the full space evenly. Two or three smaller units distributed across the facility outperform one large centralised unit because they reduce humidity pockets in corners and dead zones.
Ducted dehumidifiers are another option for facilities where the unit cannot sit on the production floor. A ducted system pulls air from the ceiling space through ductwork and returns dry air through supply diffusers.
Maintenance That Keeps Refrigerant Dehumidifiers Running
Commercial laundries are harsh environments for any equipment. Lint, detergent residue, and fabric fibres fill the air and coat every surface.
The evaporator coil is the most vulnerable component. Lint builds up on the coil fins and acts as insulation, blocking airflow and reducing extraction capacity.
A coil caked in lint can lose 40% of its rated performance before anyone notices the humidity climbing. That makes a regular maintenance schedule non-negotiable in laundry environments.
Recommended maintenance schedule:
- Weekly: Clean or replace air intake filters
- Monthly: Inspect and vacuum evaporator coil fins
- Quarterly: Check condensate drain lines for blockages, test humidistat calibration
- Annually: Full coil clean, refrigerant pressure check, electrical connection inspection
Skipping the weekly filter clean is the single fastest way to kill a dehumidifier early. Clogged filters force the compressor to work harder, which drives up energy costs and shortens compressor life.
Check that the condensate pump is draining correctly at every weekly service. A failed pump causes water to overflow internally, damaging electronics and creating the exact moisture problem you bought the unit to fix.
Running Costs and Energy Efficiency
Refrigerant dehumidifiers consume less energy per litre of moisture removed than desiccant alternatives when operating temperatures sit above 20°C. In a commercial laundry running at 28–35°C, the efficiency gap is significant.
A typical commercial refrigerant dehumidifier removing 50 to 80 litres per day draws between 1.5 kW and 3.5 kW depending on capacity. At average Australian commercial electricity rates, that translates to roughly $4 to $12 per day in running costs (Australian Government energy guidance).
Compare that against the cost of not dehumidifying:
- Linen rewash rates increase 5–15% when stored in humid conditions
- Equipment corrosion shortens machine lifespan by years
- Mould remediation costs thousands for a single outbreak
- Slip injury claims from condensation on floors create serious liability
The payback period for a properly sized refrigerant dehumidifier in a commercial laundry is typically under 12 months. That factors in reduced rewash, lower maintenance bills, and avoided remediation costs.
Energy-saving features worth looking for:
- Variable-speed compressors that ramp down once target humidity is reached
- Auto-defrost cycles for units operating near the lower end of their temperature range
- Programmable timers to run the unit only during production shifts
- Hot gas reheat that recovers waste heat to pre-warm the dry air return
Common Mistakes When Dehumidifying Commercial Laundries
After 20 years of supplying humidity control equipment, Moisture Cure Commercial sees the same errors repeated across laundry facilities. Avoiding these saves money and frustration.
- Relying on ventilation alone — exhaust fans move air but do not control humidity, and on a humid summer day the replacement air coming in can be just as wet as the air going out
- Choosing residential-grade equipment — a $400 unit from a hardware store is built for a bedroom, not a facility running eight hours a day in 35°C heat with lint-filled air
- Ignoring the exhaust system — if dryer exhaust ducts leak or vent back into the building, no amount of dehumidification will keep up
- Setting humidity targets too low — aiming for 30% RH wastes energy; a target of 50–55% RH prevents condensation and mould while keeping running costs reasonable
- Skipping the load calculation — buying on price alone almost guarantees an under-sized unit that runs flat out and still cannot hold target
The ASHRAE Handbook covers dehumidification load calculations in detail for engineers and consultants sizing commercial systems.
Next Steps for Your Laundry Facility
Getting humidity right in a commercial laundry is not complicated, but it does require the right equipment matched to your actual moisture load. A refrigerant dehumidifier is the practical, energy-efficient choice for any laundry running above 20°C.
Before you contact a supplier, gather this information:
- Current humidity readings at different points in the facility during a full production shift
- Daily linen throughput in kilograms
- Room dimensions and ceiling height
- Existing ventilation setup and exhaust extraction rates
- Any known problem areas where condensation is worst
Moisture Cure Commercial has been helping Australian commercial and industrial facilities solve humidity problems for over 20 years. The team can review your facility details, calculate the moisture load, and recommend the right unit from the humidity control solutions range. Get in touch for a consultation or site assessment.
