I am putting in a 3 ton heat pump complete with new propane furnace do I need to install a expansion valve kit and what does that do ?

Thanks Fred

Go by the factory recommendations. They are all different for different circumstances. READ the instructions that came with the unit since those instructions will tell you what to do.

For further info read this.




Thermal expansion valve - Wikipedia, the free encyclopedia

A new evaporater coil that matches your new heat pump will already have expansion built into it