1. You are not looking for a diverter, you use a simple shut off valve on one of the hoses, as I previously linked you to, and explained. At post 1428844
2. Your heater probably has a two speed motor, hence two positions CW from off.
3. Who is paramos ?
4. The best valve to use is a ball valve, rated for hot water and with the correct inlet/outlet size.

Originally Posted by danP
Good eye you have there paramos. Thanks for the link it showed I'll need a few bushings for the mounting bolts. It looks like this unit will radiate some heat all season regardless of the fan blower being on or not. Might have to install for the cold fall season and remove it again next summer.

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn