Electric Furnace

[jyoung200]

I have a Model MCE42-F25D2F-3 electric furnace. All wiring seems to be correct.The blower motor starts but just doesn't reach full speed. If I partially block the top of the plenum opening the blower motor will speed up to a normal speed. What am I missing?

[Freon]

Post the furnace model again without and dashes or other punctuation.

Look at the motor. Can you see if there's a run capacitor attached. If you can, post the motor make and model, without punctuation.

[jyoung200]

Model number is MCE42F25D2F3 I will get motor and capacitor info and post tomorrow evening.

[Freon]

Please also post the manufacturer and age of the electric furnace. I suspect it is a sick motor run capacitor which you will want to replace ASAP. They are inexpensive ($15) and easy to replace. You will need to get an IDENTICAL replacement... same microfarad and voltage.

[jyoung200]

Here is the info of the Furnace
No make or model shown anywhere I can find. Approx 15 years old

Blower

Marathon Electric
Catalog x003
Model 4WH48A1102042E P
Frame 48Y
Single phase
Type SC
RPM 1075
VAC 208 270
one third HP

Capacitator

Genteq
2L570BZ3
5uF
plus 6 to minus 6 percent
P921
50 60 Hz
370 VAC

[Freon]

Buy a new capacitor for the motor ASAP. Turn off the power to the furnace. Take the capacitor off the motor making careful notes about how you reconnect the new one. Take the capacitor to an HVAC supply house like Johnstone and get an IDENTICAL 5 microfarad, 370 volt replacement in the same physical shape (cylinder, oval or...) so it fits the motor.