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New fan radiator calculator: efficient calculation for heating and cooling

Whether it’s for a newly constructed building or an energy renovation project, nowadays it’s mandatory to efficiently and correctly calculate the output of a radiator to suit the building’s heating and cooling demand. With the new Purmo fan radiator calculator this becomes child’s play as you get easy access to the accurate output based on the size of the hydronic fan convector and the system temperatures. The meticulous calculation is carried out according to DIN 4703-3:2000-10.
fan calculator

Ulow E2


Ulow E2 is an efficient low-temperature radiator, powered by E2 technology. It’s well-suited for houses and flats where you want more output from a radiator in low-temperature systems. Ulow E2 uses built-in fans to generate forced heating convection and produces heat outputs that are up to 60% higher than traditional radiators. The hydronic fan convector has intelligent controls, allowing the fans to work on a sliding temperature scale where the water temperature must be 3°C higher than the desired room temperature. It is highly flexible, utilising central connection technology and has a “summer breeze” function for air circulation on warm days.

Fan radiator calculator


The new Purmo fan calculator allows for an easy calculation of both the heating and cooling performance of the Ulow E2. You simply determine the required height and width of the hydronic fan convector as well as the system temperatures and immediately get an accurate calculation of the radiator’s output in standby mode, comfort mode and boost mode. For practical purposes, we recommend using the comfort mode output in the calculation. Once the calculation is done, you can easily print the results to keep them on hand.

E2 technology


Thanks to the innovative E2 technology, the controller automatically switches between static (standby) and dynamic (comfort/boost) operation when needed. The static function means that the Ulow E2 hydronic fan convector functions like a traditional radiator while dynamic operation means that the integrated fans are activated, which significantly improves the heat distribution. Simply put, it’s an intelligent turbo function. The integrated fans operate silently and boost the radiators’ performance by up to 80% with increased convection.

Rapid response heating


The combination of radiant heat and enhanced convection, plus intelligent controls that automatically switch between static and dynamic operation, ensures that the Ulow E2 provides a rapid heat response even at low water temperatures so that indoor climate comfort is quickly and efficiently achieved. In addition, the E2 technology automatically and intelligently controls operation of the built-in fans to ensure maximum performance with fans that will only operate when required. The Ulow E2 is the ultimate choice when it comes to intelligent, low temperature heating.

Want to give the new Purmo fan radiator calculator a try? Simply go to the Ulow E2 product page and select the tab ‘Heat output’.