Color codes – swapping sngl phase AC motor; 3 wire to 4 wire
2 questions:
The cooling fan motor finally froze on my Rheem 10 condensing unit ; it’s used an Emerson pn: 51-21854-02 1/3 HP (Cat # 5454);
I wasn’t able to find that one, but did find a Dayton # 4M205J – with ball Bearings. It is 1/4 HP instead of 1/3, uses a bit more amps: 1.7amps on the Dayton vs 1.3 on the Emerson, and a tad taller (it’ll still fit fine), but all other specs are the same. Both are rated at 208-230 VAC.
But (DOH!) instead of the Black, Brown, and Orange leads the Emerson has; the Dayton has Black, Brown, Brown/White, and Purple.
2nd question: For good measure, I was going to replace the “dual run motor capacitor” 50/3 mfd 370V. Given that the new motor draws 1.7 amps, should a different capacitor be used? If so, what ratings? (the existing one is a single round unit w/3 double-terminals on the top).
Thanks.
Grumpy_1946
Replies
Grumpy,
Black and purple go to T1 &T2 on the contactor, The browns go to the capacitor. Capacitor shoud be fine.
I would question if this fan will now move enough air and not over heat.
KK
Fan blade replacement
Both motors are rated at 1075 RPM, same shaft size etc, and the cooling requirements would not have changed.
Are you saying a new fan blade might be required only because the HP has changed from 1/3 to 1/4 HP ?
Would Grainger be able to tell me if one is needed?
Yes the blades have to match the motor. I burned one up with the wrong blade,. Grainger can fix you up.
They can also answer the capacitor question.
Replace the fan blade too.
Fan blades are matched to the motor that drives them.
Also be sure you have the right size capacitor. It should be on the nameplate.
Dayton is a Grainger part, they will have all the info on that motor.