Excellence in
ecological solutions.
It's in our genes.
Thermal technology
Designing your boiler room, installing your steam, thermal oil, hot water or central heating boiler, fitting the pipework to get the heat to where it is needed...
Callens brings your production process or plant to the right temperature.
Air technology
Looking for the perfect cooling and ventilation system for your production process or plant?
We design and install your air handling units, chillers and cooling towers. At that, we take care of the ducting to get the conditioned air to your users.
CO2 reduction
Reduce your CO2 emissions and your energy bill through electrification, carbon capture or by using a residual as fuel.
Which technology to choose for your decarbonisation process? We always calculate the most viable option.
Service & support
With no less than 21 service engineers and burner technicians and 12 maintenance technicians, we have the most reliable, largest service team in the sector. Add to that our large stock of spare parts and it won't come as much of a surprise that we are able to respond to all your service requests quickly, 24/7. In the event of an issue, you will find the Callens service team at your door within 2 hours!

Thermal systems your production can rely on, day and night
Enjoy the robustness, energy efficiency and unrivalled service we offer as part of our thermal systems. Steam, thermal oil and hot water boilers, energy recovery systems and industrial air technologies serve as a basis for all our designs. Where possible, we also integrate renewable fuels so that you get to reduce your CO2 emissions.
We design and follow up your entire project, however complex. We engineer your system, fit it and offer you an after-sales service (maintenance and repair) that is second to none. And if you are in need of short-term extra thermal capacity, we offer you an extensive range of rental boilers.
Callens - thermal solution
Our employees are our company's driving force.
Confucius once said: “Choose a job you love, and you will never have to work a day in your life.” This nugget of Chinese wisdom is the leitmotif of our HR policy. We foster an open culture where personal input is valued. Our committed, flexible, capable employees are our most valuable asset, so we treasure them. Personal contact, countless training opportunities and career development with a healthy dose of freedom and responsibility. It works for the current 'Cauls' and is sure to work for you! Find out what it means to be a member of the 'Cauls' here.
Join the Cauls!
Do you have what it takes to become a 'Caul'? Browse our vacancies.
A focus on our employees
We regard our employees as 'Cauls'. Each one of them have an uncanny ability to focus on customers and colleagues. They are unique and are given the freedom to always be themselves.
Projects in the spotlight
Every year we complete more than 400 projects that give our customers in the most diverse sectors (food, brewing, construction, flooring, textiles, pharmaceuticals, tank storage, cleaning, hospitals, petrochemicals) everything they need to flawlessly execute small, large, complex and less complex projects.