I am getting ready to install a Hayward 140k btu heat pump which calls for a bypass valve set up for pumps over 3/4 hp and a max flow of 75 gpm. Since my Tristar vs pump is rated as 2 hp and 80 gpm at max speed and it would be a good idea anyway to bypass the heater if it had to be taken off line, I was going to use Jandy 2 way valves to make up the by pass. My question is measuring the flow for optimal performance. Can a Flowvis be installed on the heater output since it calls for a check valve before the SWG anyway or is the flow reduced as it travels through the heat pump and not the same gpm as it enters? I would install a Blue-White flow meter on the input side, but the install instructions say not to install in direct sunlight which is puzzling since they are geared towards pools. Thanks for your help.