From the moment our new 44kL pool was filled with water, our Fusion-i 12 has been quietly running in the background keeping our pool at a comfortable 28 degrees. By using a pool cover through the colder months it has no trouble in keeping the pool at this temperature. The unit works great with the J-box by utilising the existing pool pump. A big thank you to Adam for helping us choose which model and explain how the J-box works. This was by far the best money we spent during our pool construction. Highly recommended.