I bought a new blower motor for my furnace,The old blower motor was a 3 speed and new motor is a 4 speed.The place I bought it told me to hook up white on white,black on black,red on red.And leave the orange wire hanging.I have no high speed for the ac.Is there some where I need to install the orange wire,does it need to go to the common wire?

Hi... Normally, the black wire is high speed on a motor, red low speed, white common or return... an orange wire would be another speed and should be capped off, not left hanging... Power feeds back up unused speed wires... Never wire unused speeds together, it will burn up the motor... If you have no high speed on cooling you have a fan or blower relay problem... 24 volts goes down to the fan relay from the thermostat, normally a green wire, when calling for cooling or when fan is put in the on position on the thermostat... When in auto and cooling, power to pull in the compressor contactor, normally a yellow wire from the thermostat starts the compressor and the fan relay is then energized at the same time and starts the motor on high speed for cooling... If the signal doesn't come down to the blower relay, it can not change speeds on the motor... Thats its only job... Hope this helps.