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.

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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.

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EcologiCal is the name under which we strive for smarter heat energy for all: industrial companies, both large and small.

With the right alternative fuel and additional technologies, we lower your COemissions and your energy bill. In both the short and long term. Solutions are available for all. And we calculate which one is best for you.

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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!

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infographic Callens

A multidisciplinary team of experts in thermal industrial processes. 

Callens is a multidisciplinary partner who has mastered all aspects of the thermal industrial process. Our extensive expertise in steam, hot water, central heating and thermal oil boilers, energy recovery systems, industrial piping and industrial air technologies means that we are able to offer you total solutions.

We work out and follow up your entire project, however complex. We develop the system, fit it and offer you an after-sales service (maintenance and repair) that is second to none. In sum, our teams of experts provide you with an A to Z thermal solution and service. And if you are in need of short-term extra thermal capacity, we offer you an extensive range of rental boilers to safeguard your steam and hot water production. We stand and settle for nothing less than a reliable process temperature.

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. 

All vacancies   Spontaneous application

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.

'A new technical challenge every day'

As technical sales engineer I look after the technical designs and financial proposals for industrial systems. A varied, challenging role! Plus, ideas are given a fair hearing here and the support, training and team spirit is outstanding.

cyril hostyn
Cyril Hostyn
Technical sales engineer – A 'Caul' since 2017

'Opportunities + guidance create results'

In my job as a service engineer I am responsible for burner maintenance, complex interventions and the commissioning of new systems. Going out to customers every day gives me a great sense of freedom and satisfaction. The many growth opportunities at Callens, not to mention the great colleagues, are the icing on the cake!

tom parmentier
Tom Parmentier
Service engineer – A 'Caul' since 2010

'Working on the future of Callens'

I am responsible for preparing the preliminary technical drafts, the coordination, technical and financial follow-up, and the commissioning of each project. It’s as if I am running my own mini-company within Callens, and, in the process, contribute to the greater goal. That’s what makes this job so appealing.

sam mabesoone
Sam Mabesoone
Project leader – A 'Caul' since 2010

'Independence, technicity and 100 % customer focus'

As site manager, I ensure the practical and technical follow-up on site. Callens fosters an open culture where employees are listened to so that the right solution is found as quickly as possible. For years, customers' wishes and employees' needs have taken centre stage. Making the right decisions quickly is a trait that defines Callens.

Danny Houssin
Site manager – a 'Caul' since 2000

Why work at Callens?

We are a friendly and stable family business with an enviable reputation and a fabulous team. You get to work on exciting projects and to throw yourself into your job (and let off steam with your colleagues afterwards).

In sum, a place where you'll go to work smiling.

Callens logo

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.

Steam and central heating for stable warmth

Callens assisted this transport company in expanding its lanes for tank heating in the port of Ghent. An additional amount of 24 tank containers can now easily join to get reliable warmth.

Steam glues together the production phases of cardboard producer

This pioneering cardboard producer opened a brand-new site to serve his customers in e-commerce and industrial activities even faster. Thanks to the Callens steam that is now steadily flowing, the cardboard comes down the production line quickly and correctly.

Steam boiler utilizes brewery’s biogas maximally

Besides delicious Belgian beers, this brewery produces a useful extra for our steam boiler on its site: biogas. We offered a steam boiler that is ready to take up this more sustainable challenge.

2 x 40 tons of thermal certainty

The old combined heat and power system has made way for two steam boilers with an output of 40 tons of steam an hour each that keep the production process of this chemical plant running efficiently and safely. 

Medicines guaranteed safe and energy-efficient steam

An up-to-date steam system is crucial for this pharmaceutical company, for it keeps the production of chemical base components for its medicines safe and energy-efficient. The time for an overhaul had come and Callens stepped up to the plate.