The 10 Best AC Compressor Dual Run Capacitors

An AC capacitor is a small part with a big job. It gives the compressor and the condenser fan their starting push, and when it weakens, the unit runs hot, hums, or just sits there. The picks below split on one thing: the microfarad rating your system asks for, plus how the seller backs the part.

Best overall: BOJACK 45+5 uF CBB65 — the 45/5 rating covers a large share of residential condensers, and the listing prints its exact size, temperature range, and a long cross-reference list.

Best for a first-time swap: PW-45/5/R Dual Run Capacitor — the listing states it replaces both 370 VAC and 440 VAC capacitors and needs no adapters, so there’s less to get wrong on the first try.

Best for a hard-working unit: BOJACK 70+5 uF CBB65 — the highest capacitance on this list, built for bigger compressors that pull more start current.

The rest of this guide walks through each rating, the sizes, and how to read your old cap before you order.

How We Picked

A warranty statement counted too, since these parts sit in outdoor heat and vibration.

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All 10 products side by side — scroll sideways to see every column.

1. BOJACK 45+5 uF 45/5 MFD ±6% 370V/440VAC CBB65 Dual Run

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Best for: Replacing a common 45/5 condenser capacitor

This is a common dual run rating, so it’s one a lot of readers will be hunting. The listing prints the can at 2.56 inches across and 3.74 inches tall, which tells you straight away whether it drops into the same strap your old one sat in.

The three top terminals are labeled Herm, Fan, and C, matching how the old cap is wired. That labeling matters more than it sounds: on a dual run cap, the compressor and fan share one common terminal, and misreading which spade goes where is how a simple swap turns into a service call.

The listing also prints a long cross-reference list, including 97F9895, TRCD455, and RC0114. If your old capacitor carries any of those numbers, you can match it without decoding anything. The ±6% tolerance and 10,000 AFC safety rating are stated on the listing as well.

This isn’t the right pick if your system calls for a different microfarad split, and it isn’t for anyone who hasn’t read the rating off their own old cap first. The rating has to match, and no listing can tell you that.

Pros

• Rating matches many common residential condensers
• Size printed in both inches and millimeters
• Long cross-reference list for matching an old part

Cons

• Only suits systems that call for a 45/5 rating

2. BOJACK 35+5uF 35 5 MFD ±6% 370V/440V CBB65 Dual Run

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Best for: The most common replacement rating

If there’s a default dual run capacitor, this is close to it. The listing keeps the same terminal labeling and temperature range as the rest of the line, so the swap procedure doesn’t change.

The can here is narrower and taller than the 45/5 version, at 1.97 inches across and 4.14 inches tall. That shape difference is worth checking against your mounting strap before you order, because a taller can may not clear a tight bracket even when the rating is right.

The listing states the ±6% tolerance and the 10,000 AFC safety rating, and it stays at -40°C to +70°C like the others. What it doesn’t print is a cross-reference list, so you’ll be matching on the rating and the terminal layout rather than on an old part number.

Skip this one if your old cap carries a lower compressor rating than this part. A lower rating on a compressor that wants more isn’t a safe substitute.

Pros

• Rating fits a large share of home units
• Same Herm, Fan, C terminal layout as the line
• Wide stated operating temperature range

Cons

• Taller can may not fit every mounting bracket
• Listing prints no cross-reference part numbers

3. BOJACK 40+5 uF 40/5 MFD ±6% 370V/440 VAC CBB65 Dual

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Best for: Standard units that call for a 40/5 rating

This sits between the two most common ratings, and it’s the one to check for if your old cap reads 40/5 rather than 35/5 or 45/5. The can measures 2.48 inches across and 3.55 inches tall, so it’s wider and shorter than the 35/5 version.

That shorter height can help in a tight cabinet where a taller can fouls the wiring above it. The trade-off runs the other way too: a wider can needs a strap that opens far enough, and the listing gives you the number to check that against.

The terminals carry the same Herm, Fan, and C labels, and the listing prints the ±6% tolerance, the -40°C to +70°C range, and the 10,000 AFC safety rating. There’s no cross-reference list here, so match on the printed rating.

This isn’t for anyone guessing at the rating. If you haven’t read the microfarad numbers off the old cap, none of these three will reliably be the right one.

Pros

• Shorter can suits tight cabinets
• Terminal labels match the standard layout
• Rating printed clearly with tolerance

Cons

• Wider body needs a strap that opens enough
• No cross-reference numbers printed

4. BOJACK 70+5uF 70/5MFD ±6% 370V/440V CBB65 Dual Run Circular Start

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Best for: Larger compressors that pull more start current

This is the highest capacitance on the list. The can is 4.92 inches tall and 2.56 inches across, so it takes up more room in the cabinet.

If your unit calls for 70/5, substituting a smaller rating isn’t a shortcut. The listing prints the same ±6% tolerance, the same temperature range, and the same 10,000 AFC safety rating as the rest of the line.

The Herm, Fan, and C labels are there too, so the wiring side is familiar. What the listing doesn’t print is a cross-reference list, so you’re matching on the rating alone.

This isn’t the pick for a standard residential condenser.

Pros

• Highest compressor-side rating on this list
• Suits larger systems and bigger compressors
• Same terminal layout as the smaller sizes

Cons

• Tall can here, needs clearance above
• Only fits systems rated for 70/5

5. BOJACK 45+7.5 uF 45/7.5 MFD ±6% 370/440 V AC CBB65

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Best for: Units with a larger condenser fan motor

Most dual run caps pair a compressor rating with a 5 MFD fan side, but some systems run a bigger fan motor and need 7.5. That’s the whole point of this one, and it’s a difference you can’t fake with a part built for the smaller fan side.

The listing puts the can at 2.56 inches across and 3.74 inches tall, a footprint shared with the common lower-rated version. So if your old cap reads 45/7.5, this drops into the same space with the same Herm, Fan, and C terminal arrangement.

The ±6% tolerance, the -40°C to +70°C range, and the 10,000 AFC safety rating are all printed. There’s no cross-reference list, so the fan-side number on your old cap is what you match against.

Don’t buy this as an upgrade for a system whose fan motor is rated for the smaller value. A fan motor rated for 5 MFD doesn’t want 7.5 pushed through it.

Pros

• 7.5 MFD fan side suits larger fan motors
• Same can size as the common lower-rated version
• Standard Herm, Fan, C terminal labels

Cons

• Wrong choice for the far more common lower-rated setup
• No cross-reference part numbers printed

6. BOJACK 30+5uF 30/5MFD ±6% 370V/440V CBB65 Dual Run Circular Start

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Best for: Small systems and smaller compressors

This is the smallest compressor-side rating on the list, aimed at smaller systems. The can is 1.97 inches across and 3.94 inches tall, so it’s a compact part that fits where a wider capacitor would not.

Smaller units still need the right rating. The listing prints the ±6% tolerance, the -40°C to +70°C range, and the 10,000 AFC safety rating.

The Herm, Fan, and C labels are present, so the wiring is the same three-terminal job. No cross-reference list is printed here, which means matching on the rating is the way to go.

This isn’t for a standard full-size residential condenser. If your old cap reads 35/5 or higher, this is the wrong part.

Pros

• Compact can fits small cabinets
• Suits smaller compressors and systems
• Standard three-terminal labeling

Cons

• Too small for most full-size home units
• No cross-reference numbers printed

7. BOJACK 60+5uF 60/5MFD ±6% 370V/440V CBB65 Dual Run Circular Start

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Best for: Large condensers that call for a 60/5 rating

The listing for this one gives a title and a rating, and that’s about all it hands you. It’s a 60+5 uF dual run capacitor in the CBB65 round style, rated for 370V/440VAC, from the same BOJACK line as the others here.

What that means in practice is simple: if your old cap reads 60/5, this is the rating you need, and the listing confirms it exists in that value. The 60 MFD compressor side puts it in the larger-system group alongside the 70/5 part.

Beyond the rating and the voltage, the listing doesn’t print dimensions, terminal labels, temperature range, or a cross-reference list. So before ordering, measure your old can and check the terminal layout yourself, because the page won’t do it for you.

This isn’t for a standard residential unit, and it isn’t for anyone who wants the listing to confirm the fit. Check your old part first.

Pros

• 60/5 rating for larger systems
• Rated for both 370V and 440V
• Same CBB65 round style as the line

Cons

• Listing prints no dimensions or terminal details
• Only suits systems rated for 60/5

8. Z97F9848 – 35 + 5 uf MFD 440 Volt VAC

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Best for: Buyers who want an OEM-style brand name

This one carries the GE name, and the listing leans on that: it calls the part a drop-in replacement with no wiring changes or adapters needed. For a reader replacing a factory GE or Genteq capacitor, matching the brand removes one variable.

The rating is 35+5 uF at 440 volts, which puts it in the same common territory as the BOJACK 35/5. The listing states it’s made in North America, which some buyers weigh when they’re choosing between otherwise similar parts.

Note that the listing header names it a ClimaTek capacitor while the brand line says GE, so read the product description carefully before you order.

This isn’t for a system that calls for a rating other than 35/5. And if you want a printed dimension to check against your bracket, this listing doesn’t give you one.

Pros

• GE/Genteq brand name on the part
• Drop-in stated with no adapters needed
• 440-volt rating covers 370-volt uses

Cons

• Listing mixes ClimaTek and GE branding
• No dimensions printed for fit checking

9. PW-45/5/R Dual Run Capacitor

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Best for: A first-time swap with the fewest surprises

This is the pick for someone doing the job once and wanting it to go smoothly. The listing states it replaces both 370 VAC and 440 VAC capacitors, so you don’t have to work out which voltage class your old part belongs to before ordering.

It also prints a five-year guarantee, which is the only stated coverage of its kind among these listings. That’s the kind of thing that matters with a part sitting in outdoor heat and vibration year after year.

The can measures 2-3/8 inches across by 4 inches tall, and the listing cites EIA-456-A and IEC 60252-1:2001 as the standards it’s built to. It also prints the same long cross-reference list as the BOJACK part with the smaller fan side, covering numbers like 97F9895 and TRCD455.

The trade-off is the can height: at 4 inches it’s taller than some of the others here, so check the clearance above your mounting strap. This isn’t for a system that needs a rating other than 45/5.

Pros

• Replaces both 370 and 440 volt capacitors
• Five-year guarantee stated on the listing
• Long cross-reference list for matching

Cons

• Taller can needs clearance above it
• Only suits systems rated 45/5

10. 35+5 uF 35/5 MFD ±5% 370V/440VAC Dual Run Start Capacitor

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Best for: Buyers who want the tightest stated tolerance

Tolerance is how far the real capacitance can drift from the printed number, and this listing states a tighter window than most of the others here. A tighter window means the part sits closer to its rated value, which is the sort of detail a careful buyer looks for.

The listing also prints a UL certificate number, E325324, along with the same 10,000 AFC rating and the -40°C to +70°C range. The can is 1.96 inches across and 4.52 inches tall, so clearance above the strap is worth checking.

It states no wiring or adapter changes are needed, and the terminals carry the standard Herm, Fan, and C labels. The cross-reference list is long, covering 97F9834, Z97F9848, and others.

This isn’t for a system that needs a rating other than 35/5, and the extra height rules it out of some tight cabinets.

Pros

• Tighter tolerance than most here
• UL certificate number printed
• Long cross-reference list included

Cons

• Tall 35/5 can on this list
• Only fits systems rated 35/5

Also Worth Considering

PW-40/5/R Straight Cool Heat Pump is the 40/5 version of the PowerWell line, and the title names it for condenser straight cool and heat pump use at 40/5 microfarad. If your system calls for a 40/5 rating and you want the same brand family as the PW-45/5/R, this is the one to look at. The listing title gives the rating and the voltage options, so match those against your old cap.

BOJACK 45/5MFD Motor Run Fan is a 45+5 uF CBB65 dual run capacitor rated at 370V rather than the 370/440V of the main pick. That voltage difference is the whole story here: it suits a system that only needs the 370-volt rating. Check the voltage printed on your old capacitor before choosing between the two.

CBB65A MFD Dual Run Capacitor is a 35+5 MFD round dual run capacitor, and the title is about all the detail given. It lands in the same common 35/5 rating as two other picks here, so it’s worth a look if that’s your number. Confirm the can size and terminal layout from the listing photos before ordering.

How to Choose in Sixty Seconds

What rating do I actually need?

Read it off the old capacitor. The two numbers printed on the can, like 45+5, are the compressor side and the fan side in microfarads, and that pair is what you match. The voltage rating works differently: a 370/440V part covers both, so it’s the safe choice when your old cap says 370V. Never round up or down on the microfarad numbers to make a part fit. The compressor is built around its specified value, and a mismatch shows up as hard starting, extra heat, and a shorter service life. Write both numbers down before you open a single listing.

Which differences between these actually matter?

Three things separate them. First, the microfarad rating, which has to match your old part exactly. Second, the physical size of the can, because a taller or wider body may not fit the mounting strap or clear the wiring above it. Third, the fan-side number, since a few systems run a 7.5 MFD fan side instead of the usual 5. Everything else, like tolerance and the stated safety rating, is a smaller factor once the first three line up. A part with the right rating that won’t physically fit is no use to you.

What should I confirm before ordering?

Check the voltage class, the can dimensions, and the terminal layout. Most dual run capacitors here are rated 370/440VAC, which covers both common voltage classes, but confirm that on the listing you pick. Compare the printed diameter and height against the space your old cap came out of, including clearance above it. Then look at the terminal labels: Herm for the compressor, Fan for the fan, C for the common line. If your old cap has a different terminal arrangement, that’s a signal to look more closely before you buy.

Frequently Asked Questions

Can I use a higher microfarad capacitor than my old one?

No, not as a substitute. The microfarad rating has to match what your system calls for, because the compressor and fan motors are built around that value. The one place a higher number is safe is voltage: a part rated 370/440VAC, like the BOJACK 45+5 uF CBB65, works in a system that only needs 370 volts. Go higher on voltage, never on microfarads.

Do I need to discharge the old capacitor before removing it?

Yes, and this is the step people skip. With the unit shut off at the breaker, short the terminals across with an insulated screwdriver, then confirm there’s nothing left before you touch the spades. This is a job where the power being off isn’t the same as the part being safe. If you aren’t comfortable with that, call a technician.

What usually fails first on one of these?

Heat is the main reason a capacitor wears out. These sit in an outdoor cabinet through summer after summer, and the dielectric inside breaks down over time. The first sign is usually a unit that hums and won’t start, or a condenser fan that spins slowly or not at all.

Is the simplest option on this list enough for my system?

It depends on your rating, not on how simple the part is. A dual run capacitor is a straightforward component: three terminals, two values, no electronics. The BOJACK 35+5 uF CBB65 is the most common replacement rating and covers a large share of home units. But if your old cap reads 45/5, 40/5, or 60/5, the simplest option is simply the wrong one.

Closing

For most readers, the BOJACK 45+5 uF CBB65 is the pick, because that rating covers a large share of residential condensers and the listing prints the size, the temperature range, and a long cross-reference list you can match against your old part. If you’re doing the job for the first time, the PW-45/5/R Dual Run Capacitor states that it replaces both 370 and 440 volt capacitors and carries a five-year guarantee, which takes some of the guesswork out. Next step: pull the old capacitor, write down both microfarad numbers and the voltage, then match those against these listings.