I have a Rheem furnace that is at least 10 years old, could be as old as 20. I had to replace the blower motor which was a 1/4 hp and the motor I replaced it with was able to be 1/8, 1/4 or 1/2 hp. Depending on how it is wired. From reading on the capacitor I could hook this up as a 1/2 hp which I figured would give me a stronger air flow. The wiring was not exactly the same so this is what I did, I wired black to black for what I assume is the high side for the a/c and I wired red to blue which I assume is medium for the heat. I had a white wire and a brown wire from my old motor that went to the capacitor, one on each side. The new motor has two brown wires for the capacitor and plugged them in but to the same side of the capacitor and not the way the old was, one was on one side and one on the other. The blower motor will come on but only stay on for about a minute then goes off, not heating the house. Where did I go wrong ?

Read the wiring diagram on the side of the new motor,, the two brown wires (only)go to the brand new capaciter that I hope you bought for the new motor,the same label on side of motor also tells you the size capaciter it needs, the hp doesn`t have much to do with the speed/strength of the air being blown, the motor should be the same /or close to same in rpm`s as the old motor,, (example 1075 rpm) or whatever, you don`t want the blower to run to hard or the heated air that its blowing into your house will be cooled off before it gets there, the different speeds are for slower blowing for heat and harder blowing for when its in ac mode,, again look at label for wiring instructions,, let us know how it turns out

Also make sure the new motor runs in the same direction as the old motor

Thanks for the quick respone. I did not purchase a new capacitor with the motor but according to the labels on the motor and the capacitor, it will work. Should the two brown wires be connected to the capacitor on the same side or one on each side ?

Opposite sides

i did not purchase a new capacitor with the motor but according to the labels on the motor and the capacitor, it will work

NEVER replace a new motor using a old capacitor! Always replace the capacitor or you might end up replacing the new motor sooner than you think. It will work for now but pick up a new capacitor in a day or two and replace it. You will be glad you did.

I'm curious... how can a motor be multi-horsepower?

I'm curious.....how can a motor be multi-horsepower?

The windings are tapped in different areas allowing the different horse powers to develop. Actually almost any multispeed motor is a multi horsepower motor also. It kind of goes along with the old saying that the higher the RPM the more HP is developed. I hope this simple answer works for you since there are more complex answers but they are not as fun to type or read.