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Hi I'm Brian and I'm here to help!
Yes, please send the pics! In the meantime, I'll try to find some info on your furnace. Usually the capacitor is mounted directly to the blower housing near the end bell of the motor.
If that happens but nothing happens when you do the wire twist checks, then it's very possible the 24 volt transformer is blown. It is the device between the contactor and blower relay. Replace that and you may be golden.
Sorry that was meant for a previous customer. I'll have a look at the pics. I haven't found an exploded diagram yet.
Sorry again for that errant post. That was an internet hiccup! The capacitor for your blower motor will be in the other section of the furnace from the pic you sent. The pic is of the burner section. If you remove the other panel on the furnace you should see the blower housing and controls inside and the capacitor should be mounted to the blower housing. I did find out it is a 15Mfd capacitor at 440 volts ac.
Sorry for the delay, I had a response typed out and my computer display crapped. I had to get on another laptop!
It's hard to say, a blower motor won't usually run ok for two hours if the cap is bad. If the cap is weak, it might. Are there any other symptoms? Does your outdoor unit continue to run when the blower stops?
I just wanted to make sure the outdoor unit stays running when the blower quits. That wasn't very clear to me before. It would point to different problems depending on which were the case. Since the outside unit continues to run when the blower doesn't, it points to either a pretty weak capacitor, a failing blower motor or a failing furnace control board fan relay. If we could trouble shoot with a meter while in failure mode, we could determine which. If you have a meter with a capacitance function, the capacitor can be tested. Short of that, it's a replace and see scenario. The capacitor is the cheapest so I would try that first like you were about to do. If that turns out not to be it, then it's a toss up whether it's the board or the motor. An amp clamp meter might help but voltage probing with a meter during the failure condition is the only true way to see what's failing.
I did find a manual and a parts list for the furnace but no exploded parts diagram in either. The capacitor should be mounted on the side of the blower housing near the the motor.