Electrical Questions, Straight Answers
Can I use a 440V capacitor instead of a 370V?
Yes — voltage is a ceiling, not a match requirement. A 440V cap on a 370V application is fine and it's why most trucks just stock 440V rounds. Never the reverse. MFD still has to match exactly.
Why do run capacitors keep failing on the same unit?
Heat, voltage spikes, or a motor on its way out. Check the fan motor's amp draw against nameplate — a dragging motor cooks caps as a symptom, not a cause. Also look at where the cap lives: baking against a hot compressor shortens its life, and undersized replacements fail fast.
Capacitor is bulging on top — is that actually bad or just cosmetic?
It's done. The bulge is the pressure-relief top deforming, which means the dielectric has been cooking. It may still read close to spec today and strand the customer next week — replace it while you're standing there.
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