This is a "4-wire", meaning there are a total of 5 when you include the ground. Unfortunately, the contractor that installed it originally used one color of wire for all wires 4 wires (ground is different, at least) so I lost track of which wire went where and fried my TBS 213 pneumatic switch on my first attempt. I'm about to order a new pneumatic switch (probably TBS 3213) but I need to know if there is any reason this needs to be a double pole and throw switch. It seems from the wiring diagram for the motor that a single pole double throw would work just fine since we control ON/OFF with the T-103 timer and the pneumatic only controls Hi/Lo. It looks like the installer must have ran both wires to the common terminal on the motor instead of jumping them on the switch as indicated in the diagram. Advice?