
U.S. Seal Run Capacitor 25 MFD 370V Round, RD-25-370
30 day returns · Easy, with prepaid labels provided
Quick overview
- Twenty five microfarads Rated 25 MFD, the value that has to match what the motor calls for.
- Three seventy volts A 370 volt rating, the standard class for run capacitors on these motors.
- Round case The round body style, so check the shape as well as the rating against the old part.
- Run, not start A run capacitor stays in circuit the whole time the motor is turning.
- The classic hum A dead run capacitor leaves a motor humming and refusing to spin up, or running hot.
- Discharge it before you touch it Capacitors hold a charge after the breaker is off, so treat the terminals as live until the old one is safely discharged.
Need a hand?
Frequently bought together

U.S. Seal Run Capacitor 25 MFD 370V Round, RD-25-370
Similar products
Other products people compare with this one.
SuperPro 30 MFD 370V Round Run Capacitor, 12717$3499
U.S. Seal Run Capacitor, 30 MFD, 370vac, 5VR0303$3099
Century Capacitor 25 MFD 370V, 628318-307$3199
Century Motor Capacitor 161-193 MFD 125V, 11914$1699
Century Start Capacitor, 189/227 MFD, 125 VAC, 1-7/16" x 2-3/4", 610807-007$1799
SuperPro 125V Start Capacitor, 161/192 MFD, 11914$1699
Century Stationary Single Speed Switch, 629002-001$3699
Pentair Protective Pool Motor Cover, R221016$3799
U.S. Seal Run Capacitor 50 MFD 370V, RD-50-370$4299
SuperPro 50 MFD 370V Round Run Capacitor, 12725$4799
Century Run Capacitor, 30 MFD, 370 VAC, 1-3/4" x 2-7/8", 628318-308$5899
Century 1 HP Pump Motor, 230/115 Volt, 3450 RPM, Round Flange, 56J Frame, ODP, UST1102$28799
Century Motors AO Smith Threaded Shaft Motor 1HP 115V/230V 56 Round Frame | ST1102$33399
Century Motors A.O. Smith Keyed Motor 1HP 115V-230V Full-Rate 56 Round Frame | SK1102$34099
Century Motors AO Smith Threaded Shaft Motor 1HP 115V/230V 56 Round Frame Full-Rate Energy Efficient | CT1102$39599
Century Motors Magnetek Threaded Shaft Motor 1 HP 115-208-230V 56 Round Frame | B654$42899
Century Motors Magnetek Keyed Motor 1.5HP 115V 230V Full-Rate 56 Round Frame | B123$45599
Century Motors Magnetek Keyed Motor 2HP 230V Full-Rate 56 Round Frame | B124$53499
Century Motors Magnetek Threaded Shaft Motor 2HP 115 230V 56 Round Frame Full-Rate | B836$57799
Century Motors Magnetek Threaded Shaft Motor 3HP 230V56 Round Frame Full-Rated | B131$65999
Product details
This is the U.S. Seal RD-25-370, a round run capacitor rated at 25 MFD and 370 volts. It is a replacement motor capacitor for pool pump motors.
What a run capacitor does
A single phase motor cannot get itself turning without help. The capacitor supplies the phase shift that starts it, and a run capacitor stays in circuit the whole time the motor is spinning to hold that shift. It is one of the more common failures on a pool pump and one of the cheapest to put right.
Matching the part
Two numbers decide the fit. The capacitance in microfarads has to match what the motor was built for, because a different value changes how the motor behaves under load. The voltage rating can be equal to or higher than the original but never lower. Check the case shape too, since this is the round style and it has to sit in the mounting the motor provides.
Safety
A capacitor stores energy and can stay charged long after the power is switched off. Turn off the breaker, discharge the old capacitor safely, then disconnect it. If that is not something you are set up to do, hand the job to a service technician.
| Brand | U.S. Seal |
|---|---|
| Manufacturer part number | RD-25-370 |
| Type | Run capacitor |
| Capacitance | 25 MFD |
| Voltage | 370V |
| Case shape | Round |
| Application | Pool pump motor |
| Shipping weight | 0.2 lb |
| Ships | Parcel |
Request a quote
Need a volume price, a freight quote, or pricing in writing before you order? We reply the same business day.
Customer reviews
More from US Seal
U.S. Seal PS200 Mechanical Seal Assembly$1199
U.S. Seal PS1000 Shaft Seal Assembly$699
U.S. Seal Pump Shaft Seal Assembly PS201$699
U.S. Seal Heavy Duty Mechanical Seal Assembly (PS200), PS-3867$1599
U.S. Seal Heavy Duty Seal Assembly, PS-3868$1999
U.S. Seal PS-851 Seal Assembly$1199
U.S. Seal Mechanical Seal, 13/16" ID (Generic), PS-4231$2599
U.S. Seal Shaft Seal Assembly (Generic), PS-3890$2299
U.S. Seal Heavy Duty Salt and Ozone Service Shaft Seal, Viton Carbon, PS-3865R$1599
U.S. Seal Mechanical Seal, 5/8" ID (Generic), PS-4231-OS$1999
U.S. Seal Run Capacitor 50 MFD 370V, RD-50-370$4299
U.S. Seal Run Capacitor, 30 MFD, 370vac, 5VR0303$3099
U.S. Seal Shaft Seal Assembly, 3/4" Shaft, PS-601$1999
U.S. Seal Shaft Seal Assembly, 3/4" Shaft, Extra Heavy Duty, Saltwater/Ozone Pools, PS-3986$2799
U.S. Seal 6203 Motor Bearing, RBL-6203-LL$1299
U.S. Seal PS100 Replacement Pump Seal Assembly$699
U.S. Seal Shaft Seal Assembly PS2131$1599
US Seal CAPACITOR 35MFD 370V ROUND | RD-35-370$3599
US Seal ASSEMBLY 3/4" CUP MTD | PS-201V-CMS$2899
US Seal CAPACITOR 189/227 MFD 125V | BC-189$1499
Questions and answers
What people ask about this product, answered by our pool techs.
How do I know this is the right capacitor?
Is this a start capacitor or a run capacitor?
What are the signs of a failed run capacitor?
Does the round shape matter?
Get your unadvertised price ›






