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Guide
How to choose a replacement motor run capacitor
A run capacitor is matched to its motor by a few numbers printed on its label. Read them off the old part, check them against this list, and send them to us for a quote.
Read these from the label
| Label marking | What it means | How to match it |
|---|---|---|
| µF or MFD | Capacitance in microfarads. MFD and µF mean the same thing. | Use the same value. The motor is designed around it. |
| VAC | The maximum AC voltage the capacitor is rated for. | Use the same rating or higher. Never lower. |
| Two µF values, e.g. 35+5 | A dual capacitor: two capacitors in one case, usually compressor + fan in an air conditioner. | Replace with a dual of the same two values, or two singles. |
| ± % | Tolerance: how far the real value may differ from the printed one. | Same tolerance or tighter. |
| Temperature range, e.g. -40/+70°C | The ambient temperature the capacitor is rated to work in. | Same range or wider, especially in outdoor units and pumps. |
| Terminals or leads | Quick-connect tabs, or wire leads. | Match the connection so it fits the existing wiring. |
| Case shape and size | Round, oval or rectangular, and its dimensions. | Must fit the bracket or housing. Oval cases fit tight spaces such as fan switch housings. |
Safety: a capacitor can hold a charge after the power is off. Disconnect power and have a qualified technician discharge it before handling.
Find the part
- AC motor run capacitors for air conditioners, pumps and appliances
- SH 2000VAC oval capacitors in 2, 3, 4 and 5 µF (MFD) for ceiling fans and small motors
- Air conditioner, ceiling fan and water pump guides
Send us a photo of the old label and the quantity. We will match it and quote.
Send us your part details
Tell us the part, rating and quantity you need. We reply by email with price and availability.