The following heat pump diagnostic flow charts and accompanying wiring diagrams are to be used in diagnosing and repairing Hayward & Summit branded pool heat Megaline Fi. The heat pump for large volumes A heat pump that knows to be discreet Reversible heat pump for small swimming pools and spas NOTE: The water in and water out are "reversed" from my old heat pump. The manually has all the details needed for a successul install.This manual contains installation, service and maintenance. Please read this manual carefully before you open or maintain the unit. The manufacturer of this Please read this manual carefully before you open or maintain the unit. The The Swimming Pool Heat Pump Unit heats the swimming pool water and keeps the. Hayward HeatPro Above Ground Heat Pump 50K BTU | Horizontal Fan | W3HP50HA2 · 45,000 BTU heating capacity · Lower energy requirements than natural gas and propane