The following system layouts were measured and tested by the Institute for Thermodynamics and Heat Engineering (ITW) at the University of Stuttgart.

• ITW System Layout Broetje
• ITW System Layout Buderus
• ITW System Layout Feuron
• ITW System Layout Ratiotherm
• ITW System Layout Teufel und Schwarz
• ITW System Layout Wagner
• ITW System Layout Weishaupt