Hi @Ardian,
Because I have never tested this swimming pool in any real project, I will need to find some time to test it. I’d suggest you to post the questions to https://unmethours.com/questions/ where you might find someone has done this and understand the technical side that how SwimmingPool works in EnergyPlus.
I would also suggest you to check EnergyPlus example file 5ZoneSwimmingPool.idf (167.9 KB) and compare with what you have modeled.