Heat exchanger supply/return temperatures too close together
The error message
This error occurs on the parameterisation of the heat exchanger. In this example, the design temperature of the end unit is set to 70/50°C, and the primary temperatures of the heat exchanger are set to 70/50°C. Due to the efficiency of the heat exchanger, it is impossible to have equal primary and secondary supply temperatures (this also counts for the return temperatures). Primary needs to be higher than secondary, with a certain deltaT. Based upon this, Hysopt will now be able to calculate a UA-value.