Master Header Logo


Master Brand Header 1
Master BC 121 – evaporative cooler
Master BC 121 – evaporative cooler

BC 121 – evaporative cooler

Portable air coolers

Cool your factory, hangar or workshop for less. Our portable evaporative coolers offer a cost-effective alternative to traditional air-conditioning and create a comfortable working environment for your employees or customers.


Key features

  • Efficient and durable spot cooler for industrial applications
  • Quiet running even with large air flow
  • Automatic swing function as standard
  • Large water tank for longer operating hours
  • Large, durable wheels with brakes allow easy movement
  • Connect water hose or refill tank manually to offer comfort to your employees
  • Corrosion-resistant plastic casing
  • Air filter included to enable easy maintenance
  • Remote control to easily adjust speed
  • UV lamp, disinfecting the water

Benefits of evaporative cooling

  • The use of Master air coolers strongly reduces the CO₂ impact compared to air-conditioners
  • Clean air that reduces the risk of bacteria and virus
  • No chemicals or refrigerants
  • Low energy consumption
  • Virtually maintenance-free equipment

How does it work

The heart of the evaporative cooling system is the cooling pad where the water evaporates and the air passing through the pads is cooled. Evaporative cooling pads are manufactured from fluted cellulose sheets that are glued together. The material is chemically impregnated with special compounds to prevent rot and ensure a long service life and easy maintenance.

Evaporative cooling and humidity

A given volume of air at a certain temperature and pressure is capable of absorbing and holding a certain amount of water vapour. If that volume of air contains 50% of the moisture it is capable of holding, we say it is at 50% relative humidity.

The hotter the day, the drier the air, the more cooling can be done by means of evaporation. In other words, the cooling effect is best when you need it most.

Our evaporative coolers are developed to work well in high-humidity environments too, however, and will remain much more efficient than a simple fan that just circulates warm air.

Our coolers will increase humidity by 2 to 5%, depending on temperature and humidity in the environment you want to cool. The slight increase is not noticeable in ventilated areas where the air produced by the unit is exhausted.

Product specifications

Cooling pad


Air flow


Loaded air flow


Maximum area


Power consumption


Power supply


Rated current


Water consumption


Tank capacity


Direct water connection


Tank level control


Sound level


Product size (l x w x h)

1050 x 600 x 1460

Box size (l x w x h)

1120 x 680 x 1650

Net/gross weight




Our tools


Master 3-year limited warranty

Register your Master product here to take advantage of the benefits of the 3-year limited warranty.

Download app

Master Climate Solutions app

Use the Master Climate solutions app to calculate power and get recommended heating, cooling, drying or ventilation products for your work area.

Accessories and consumables

Master dust cover 4241 160
Master Top Badge

Product code: 4250.414

Accessory for BC 121

Where to Buy Icon

Looking to buy?

Get in touch and we will connect you with the right office or dealer.

Looking for Spares Icon

Looking for spares?

The direct route to spare parts for your equipment.

Looking for Servicing Icon

Looking for servicing?

Contact us for help in finding the right service professional near you.

Related products

Master BC 221 – evaporative cooler
Master Top Badge

Portable air coolers

Green and cost-effective cooling unit with integrated UV light. Ideal for open and semi-open spaces of up to 250m².

Master BC 341 – evaporative cooler
Master Top Badge

Portable air coolers

Green and cost-effective cooling unit with integrated UV light. Ideal for open and semi-open spaces of up to 400m².

Master BCB 19 – evaporative cooler
Master Top Badge

Portable air coolers

Ideal for events and festivals, the BCB 19 offers ductable air flow and power enough for spaces up to 400m².

Featured insights

Insights Content cooling aircraft
Master Bottom Badge

Find out where evaporative cooling units outperform other solutions in the hottest temperatures.

Photo of Maurice van der Kooij
Maurice van der Kooij 7 min read
Master factory summer web
Master Bottom Badge

Why we recommend evaporative air cooling

Photo of Maurice van der Kooij
Maurice van der Kooij 4 min read
Insights Content Evap Cooling Productivity
Master Bottom Badge

How spot cooling increases your team’s output

Photo of Maurice van der Kooij
Maurice van der Kooij 5 min read

Enquire about this product

Complete your details below and the right person from our expert team will get back to you.
For service and spare parts enquiries please include serial number and product type in the Message field.