HQUAWS-DV02 Hot Water Drain Valve, Temperature Management Valve for HQUA OWS-6 UV Water Purifier, 110℉ Open, 1/2" FNPT Inlet, 1/2"MNPT Outlet

I plan to install in a cottage in very cold climate that will require the unit to be drained every year. Can it be installed upside down to drain?

Does this unit have a light to indicate it is working properly?

My water pressure is 80 psi, and I get 1.2 gpm on my sink, will the water pressure change significantly?

What size thread are the fittings?