Davey Silensor SLL400 Capacitor

The Davey Silensor SLL400 single-phase pool pump is listed with a 25 µF (25 uF / 25 MFD), 450 VAC CBB60 motor-run capacitor with lug (spade) terminals, and this CapacitorsNZ capacitor is made to that rating. The SLL400 model code on the label identifies the pump, not the capacitor value, so read the µF printed on your old capacitor and match that number before you order.

Choosing the right capacitor for the Davey Silensor SLL400

Three things need to line up. The capacitance must match the old part, normally within plus or minus 5%. The voltage rating must be the same as the old capacitor or higher, and this one carries a 450 VAC rating. The terminals should suit your wiring, and this capacitor has lug (spade) terminals in a CBB60 cylinder body.

If your old capacitor shows a different µF value, order that value instead. The Silensor SLL capacitor guide has more help with reading the label.

Signs the Silensor SLL400 capacitor is failing

On a single-phase motor that uses a run capacitor, the capacitor stays in circuit the whole time the pump is running. Heat and age slowly reduce its capacitance until the motor no longer gets a clean start.

• the motor hums but won’t turn, or starts only after the shaft is spun by hand
• the overload or breaker trips soon after start-up
• the motor runs hot and sluggish
• the capacitor case is swollen, cracked or leaking

Other pumps listed with a 25 µF rating

We also list a 25 µF capacitor for the Silensor SLL150, Silensor SLL200, Silensor SLL300 and Silensor SLS300. The same part is sold on its own as our 25 µF 450 V CBB60 capacitor. A shared listing doesn’t guarantee your pump has the same value, so check the old capacitor first.

Swapping the Silensor SLL400 capacitor safely

Isolate the power first. A capacitor can hold a charge after the pump is switched off, so discharge it across the terminals with an insulated resistor before touching anything. Photograph the wiring, move each wire across to the matching terminal on the new capacitor, and secure the new body firmly so it can’t rattle against the motor.

Doing the shaft seal at the same time? The Silensor SLL400 service kit includes this capacitor and the matching seal, and the Davey service kits page covers other Davey models.

Before you order

Check the old part before fitting: match the µF printed on your old capacitor.

What size capacitor does a Davey Silensor SLL400 take?

Our listing for the Davey Silensor SLL400 is a 25 µF 450 VAC run capacitor with lug terminals. Match the µF printed on your old capacitor before ordering.

My Silensor SLL400 capacitor shows a different µF. Which one should I buy?

Buy the value printed on your old capacitor. The label on the capacitor fitted to your Silensor SLL400 takes priority over any listing.

Can I use a higher-voltage capacitor on my Silensor SLL400?

Yes. A higher voltage rating than the old capacitor is fine on a Davey Silensor SLL400 as long as the µF matches. This capacitor has a 450 VAC rating.

Does the Silensor SLL300 use the same capacitor as the SLL400?

We list the Silensor SLL300 with the same 25 µF rating as the SLL400. Pumps can vary, so check the value on your own capacitor.

How do I know if the Silensor SLL400 capacitor is faulty?

A Silensor SLL400 that hums without turning, needs a spin by hand to start, or trips the breaker soon after start-up often has a weak capacitor. A swollen, cracked or leaking case means the capacitor should be replaced.

What if it doesn't fit?

If you're unsure, send us a photo of your old part and the pump's label before ordering.