Thermal oil boilers

Over the past 50 years or so, Callens has successfully completed more than 1000 thermal oil boiler projects, making us the undisputed market leader in the thermal oil segment.

More than 1000 references

Designing and installing thermal oil boilers that achieve temperatures above 300°C has become second nature to our thermal engineering specialists over the years. Closed-loop thermal fluid heat transfer systems are the ideal solution for production processes that call for temperatures that are not only extremely high but must also be extremely accurate.

Our thermal oil boilers with an output of 100,000-12.5m kcal/h provide the precise heat production processes in the smallest to the largest industrial sectors need.

Our product range

  • Thermal oil boilers
  • Output: 100,000-12,500,000kcal/h
  • Vertical and horizontal
  • Bio)gas – heating oil – dual fuel
  • Emissions in accordance with Vlarem II


To give you an idea of the extent of our expertise in thermal oil boilers, we thought it might be nice to offer you a selection of our most impressive projects. Hot off the press!