Quote Originally Posted by Mr Bill View Post
You're missing something here, if the system was designed to run on high speed, if you run it on a slower speed, you have the possibility of not enough air across the heat strips, and tripping the high limits, or even worse burning a heat strip into. If you really want it done right, because at this point you don't know who's done what, google for a product manual, or call the mfg. there's only one way, the right way.
Lots of air handlers came with a 3 speed motor, but only use 1 speed. The contractor is/was suppose to set it to the proper speed for the system when the system was installed.