I have a water to water geothermal heating system. My now discontinued Triangle Tube indirect tank is having problems and eventual replacement is expected. This entails different tanks and plumbing changes. My 4 ton Waterfurnace heat pump is attached to a 120 gallon indirect dual coil tank keeping the water temperatures between 115 and 105. The heated water being circulated thru the floor has a Taco 3 way mixing valve with outdoor reset and adjustable ratio dial. A recent visit by local Geothermal service company recommended removing the mixing valve from my system during the tank replacement. His theory was not to temper the water going to the floor as this would lead to lower heat pump cycling time and reduced power use. I am seeking opinions as to accept this contractors advice or stay with my current 15 year old system design? My limited understanding of outdoor reset controls makes sense if your variably controlling water temperature based on outdoor air temperature changes. Although, my system water temperature is in a fixed constant range, with the floor water being tempered via the outdoor reset back to the tank. I see his point. Any suggestions? Thank you for your time:)