We live in northern (just south of Green Bay) Wisconsin. We have three Solara solar panels for our 28 foot/52 inch round 17,000 gallon pool that was installed this year. We use a solar blanket. We have researched heat pumps as a way to get an additional water temperature boost as there can be chilly days in summer. (We mainly plan on using it June - August). We were thinking about getting the Raypak 113,000 BTU (RS6350ti-E-QT quite model). A web dealer however said he prefers the Aquacal heat pump. Does anyone have a preference and what BTU size would you recommend? Thank you very much for your time.