Step 3: Calculating & troubleshooting your model

The following part of the detailed model takes the drawn model and moves into troubleshooting (removing mistakes from the model) and calculating (removing system-wide mistakes in the drawing). Some examples can be found here: System Check

When the model is drawn fully, you can use the system check to verify whether there are faults in the system, there are multiple different faults expected to find. Often these are related to unconnected nodes as shown below (Hysopt will show these nodes with an orange circle, either to be deleted or connected through piping or canvas linking).

After the system check proves to be successful, you can go through the 3 steps of calculation (Compute design flows, Select pipes & Optimize system components), during which Hysopt will also show possible faults. The example below is an unconnected pipe, which is drawn using the pipe end, which as standard temperature uses a flow of 75°C, while the rest of the building works at 70°C. Hence, there is a supply temperature mismatch, easily fixed by overwriting the supply temperature on the pipe end to 70°C.

A very important check is the pumps and following KV values in the circuit, in the example below the pressure drop over the overdoor heaters is set way too high (due to a typing error) and hence, the total pressure drop in the system is way to hard.

To check this press the pump and 'ctrl + e', this will show the most critical (highest pressure drop) path and lead you right to the issue. You see a blue track of the highest pressure drop, which you can follow to the problem. A similar issue might be found whenever a pump is undersized for the circuit.