Error "Initial conditions solve failed to converge" when connecting two Simscape Fluid examples

I am trying to connect two Simscape Fluid examples called "Residential Air Source Heat Pump" and "Stratified Hot Water Tank". The simulation works when both models are not connected. However, connecting the control signal of a circulation pump from Residential Air Source Heat Pump to Stratifiend Hot Water Tank (as shown in the screenshot below), I get the following error message:

I would really appreciate some help

Answer 1

[Rishi]

Hi Fabian,

I understand that the Simscape solver is not able to solve the initial conditions target in your model.

You can try the following steps to fix your issue:

• If you have set the initial conditions of different blocks, ensure the “Start from steady state’ check box in the Solver Configuration block is unchecked. To learn more about Initial Conditions Computation, you can refer the following documentation: https://www.mathworks.com/help/simscape/ug/how-simscape-simulation-works.html#:~:text=Statistics%20Viewer.-,Initial%20Conditions%20Computation,-The%20Simscape%20solver
• Prior to simulating the model, you can use the Variable Viewer (Debug > Simscape > Variable Viewer) to check the results of the initial condition computation for the model and to see which of the block-level variable initialization targets have been satisfied. You can find more information about Variable Viewer in the following documentation: https://www.mathworks.com/help/simscape/ug/variable-viewer.html

A similar issue has been addressed in this MATLAB Answer:

https://www.mathworks.com/matlabcentral/answers/526648-why-does-my-simscape-fail-to-solve-initial-conditions-when-i-enable-the-start-from-steady-state-op

Hope this helps.