The above diagram shows early Y valve shipments of the Compool LX22. It had a reversible plug which is no longer used. The LX220 replaced the plug with a three position switch on the rear of the Valve Operator (VOR). If the valve is installed backwards [reverse staged], simply change the switch position to cause the valve to rotate in the opposite direction. The 2 inch Y valve is now available as an option. Current SolarAttic Pool Heater shipments are sent with a 2 inch T valve. Its output ports are 90 degrees from the input port [forming a T].