Can I use a higher MFD start capacitor?
Furthermore, can you use a higher rated capacitor?
Generally speaking there is no problem using capacitors of a higher voltage rating. If you use capacitors rated for higher voltage, these are often in bigger can sizes, which means lower ESR, so in some situations the ESR may drop below some safe threshold and then the linear regulator may become unstable.
One may also ask, what happens if you use the wrong size capacitor? If the wrong capacitor rating or a poor quality capacitor is used, then the motor will not have the correct phase angle between the current and the voltage, and consequently the motor torque or rotational force will be affected. Depending on the motor load, this may result in a reduction in the motor's overall speed.
Keeping this in view, can you replace a capacitor with a higher uF HVAC?
In any HVAC unit, the capacitor must match the motor. The voltage can go higher if necessary but never lower while the MFD (uf) should always be the same.
What is the difference between uF and MFD capacitors?
In short, the answer is yes — mFd is the same as uF- which is also the same as the symbol 'µ' as seen in 'µF'. Technically 'mfd' represents 'milliFarad' while 'uF' stands for 'microFarad' which is an order of magnitude smaller. Some older capacitor manufacturers used 'mF' in place of uF on their capacitors.