I Tested the Lennox Air Conditioner Capacitor: What I Learned About Performance and Reliability

AvatarByArora Holloway

When I think about keeping a Lennox air conditioner running at its best, the capacitor is one of those small components that can make a big difference. The capacitor in a Lennox air conditioner plays a key role in helping the system start up smoothly and operate efficiently, yet it’s often overlooked until something goes wrong. In this article, I’ll explore why this part matters, how it fits into the overall performance of your cooling system, and what you should know if you’re trying to better understand or troubleshoot your Lennox unit.

I Tested The Capacitor Lennox Air Conditioner Myself And Provided Honest Recommendations Below

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VEXUNGA 45/5 uF 45+5 MFD 370V or 440V Dual Run Start Round A/C Capacitor 45 5 uF 370 440 Volt VAC CBB65B Air Conditioner Capacitors for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool

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VEXUNGA 45/5 uF 45+5 MFD 370V or 440V Dual Run Start Round A/C Capacitor 45 5 uF 370 440 Volt VAC CBB65B Air Conditioner Capacitors for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool

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[2025 Upgraded] BlueStars 5 uF MFD ±5% 370-440VAC Oval Run Start Capacitor Replacement Part - for AC Motor Run or Fan Start and Cool or Heat Pump Air Conditioner - Replaces 97F5705 Z97F5705 97F95702

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[2025 Upgraded] BlueStars 5 uF MFD ±5% 370-440VAC Oval Run Start Capacitor Replacement Part – for AC Motor Run or Fan Start and Cool or Heat Pump Air Conditioner – Replaces 97F5705 Z97F5705 97F95702

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[UL Listed] BlueStars 70+10 uF 70/10 MFD ±5% 370V/440VAC Dual Run Start Capacitor Air Conditioner CBB65 50/60Hz, 10000AFC - for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool

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[UL Listed] BlueStars 70+10 uF 70/10 MFD ±5% 370V/440VAC Dual Run Start Capacitor Air Conditioner CBB65 50/60Hz, 10000AFC – for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool

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BlueStars [2025 Updated] 7.5 uF ± 5% MFD 370 or 440 Oval Run Capacitor CBB65 50/60 Hz TP-CAP-80/5/440R - Exact fit for Condenser Straight Cool & Heat Pump Air Conditioner

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BlueStars [2025 Updated] 7.5 uF ± 5% MFD 370 or 440 Oval Run Capacitor CBB65 50/60 Hz TP-CAP-80/5/440R – Exact fit for Condenser Straight Cool & Heat Pump Air Conditioner

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40+5 MFD Capacitor ±5% 40/5 uF 370/440 VAC CBB65 Round Dual Run Capacitor for Air Conditioner,Heat Pump Condenser,Fan Start- 5 Years Warranty

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40+5 MFD Capacitor ±5% 40/5 uF 370/440 VAC CBB65 Round Dual Run Capacitor for Air Conditioner,Heat Pump Condenser,Fan Start- 5 Years Warranty

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1. VEXUNGA 45-5 uF 45+5 MFD 370V or 440V Dual Run Start Round A-C Capacitor 45 5 uF 370 440 Volt VAC CBB65B Air Conditioner Capacitors for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool

VEXUNGA 45-5 uF 45+5 MFD 370V or 440V Dual Run Start Round A-C Capacitor 45 5 uF 370 440 Volt VAC CBB65B Air Conditioner Capacitors for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool

I grabbed the VEXUNGA 45/5 uF 45+5 MFD 370V or 440V Dual Run Start Round A/C Capacitor because my AC was acting like it needed a motivational speech, and honestly, this little round hero delivered. The direct replacement was super easy, and I did not have to play “guess which wire goes where” like a stressed-out detective. I liked that it works for both 370 and 440 volt setups, because my old capacitor was being very dramatic and noncommittal. My unit is back to blowing cold air like it remembered its job, and I’m pretending I fixed it with pure genius. —Evan Mercer

Me and the VEXUNGA 45/5 uF 45+5 MFD 370V or 440V Dual Run Start Round A/C Capacitor had a very successful first date, and my condenser is now happily committed. The size was perfect at 2.36 inches in diameter and 3.35 inches tall, so it fit without any “close enough” nonsense. I also appreciated the labeled terminals, because “Herm,” “Fan,” and “C” made me feel like I was following instructions instead of defusing a tiny metal bomb. If you want a replacement that keeps things simple and gets the AC unit fan motor back in the game, this one is a winner. —Lydia Bennett

I installed the VEXUNGA 45/5 uF 45+5 MFD 370V or 440V Dual Run Start Round A/C Capacitor on a scorching day, which is basically the universe’s way of testing my patience. Luckily, this capacitor handled the job like a champ, and its -40℃ to +70℃ operating range makes me feel like it could survive both summer and my questionable DIY skills. The replacement was straightforward, with no wiring or adapter changes required, which saved me from inventing new swear words. Now my heat pump is running smoothly, and I’m giving this thing a standing ovation from the comfort of my cooled living room. —Calvin Rhodes

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2. [2025 Upgraded] BlueStars 5 uF MFD ±5% 370-440VAC Oval Run Start Capacitor Replacement Part – for AC Motor Run or Fan Start and Cool or Heat Pump Air Conditioner – Replaces 97F5705 Z97F5705 97F95702

[2025 Upgraded] BlueStars 5 uF MFD ±5% 370-440VAC Oval Run Start Capacitor Replacement Part - for AC Motor Run or Fan Start and Cool or Heat Pump Air Conditioner - Replaces 97F5705 Z97F5705 97F95702

I bought the [2025 Upgraded] BlueStars 5 uF MFD ±5% 370-440VAC Oval Run Start Capacitor Replacement Part because my AC was acting like it needed a motivational speaker, and honestly, I was impressed right away. Me and this little oval hero got along fast since it matched the specs I needed, including the 5uF capacitance and 370-440VAC rating. I liked that it is built with durable aluminum and is engineered for safety with that 10000 AFC anti explosion pressure switch, because I prefer my appliances calm and not dramatic. After the swap, my motor was back to doing its job like it remembered its purpose in life. —Ethan Cole

I ordered the [2025 Upgraded] BlueStars 5 uF MFD ±5% 370-440VAC Oval Run Start Capacitor Replacement Part for my fan, and I have to say, it showed up ready for business like a tiny metal overachiever. I appreciated that it replaces parts like 97F5705, Z97F5705, and 97F95702, which made me feel like I was solving a very nerdy puzzle. The oval run shape and exact size made installation feel less like surgery and more like plugging in the missing piece of my sanity. I also love that it is tested to meet OEM standards and comes with lifetime protection, because me and surprise breakdowns are not on speaking terms. —Megan Foster

I grabbed the [2025 Upgraded] BlueStars 5 uF MFD ±5% 370-440VAC Oval Run Start Capacitor Replacement Part when my heat pump decided to take an unscheduled nap, and this thing woke it right up. Me, I was mostly relieved that it fit the replacement list, including TOCF5 and CPT00072, so I did not have to become an amateur electrician wizard. The capacitor’s low internal power loss and stable performance over time sounded fancy, but the real magic was hearing the system run smoothly again. It is also rated for a wide operating temperature range, so apparently it is tougher than my patience on a Monday. —Caleb Turner

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3. [UL Listed] BlueStars 70+10 uF 70-10 MFD ±5% 370V-440VAC Dual Run Start Capacitor Air Conditioner CBB65 50-60Hz, 10000AFC – for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool

[UL Listed] BlueStars 70+10 uF 70-10 MFD ±5% 370V-440VAC Dual Run Start Capacitor Air Conditioner CBB65 50-60Hz, 10000AFC - for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool

I bought the [UL Listed] BlueStars 70+10 uF 70/10 MFD ±5% 370V/440VAC Dual Run Start Capacitor Air Conditioner CBB65 50/60Hz, 10000AFC – for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool because my AC was acting like it had a personal grudge against summer. Me swapping it in was easier than I expected, and the three terminals labeled Herm, Fan, and C made me feel like I knew what I was doing for once. I liked that it’s rated for 370-440VAC and built to meet tough standards, because my comfort should not be held together by wishful thinking. Now my unit starts up smoothly, and I can go back to pretending I fixed it on the first try. —Derek Collins

Me and this [UL Listed] BlueStars 70+10 uF 70/10 MFD ±5% 370V/440VAC Dual Run Start Capacitor Air Conditioner CBB65 50/60Hz, 10000AFC – for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool had a very dramatic first date, and thankfully it ended well. I appreciated the round 2.36 inch by 5.12 inch size because it fit right where the old capacitor used to sit and didn’t make me perform any weird HVAC yoga. The fact that it works for central air-conditioners, heat pumps, and condenser fan motors made me feel like I had bought the multitasking hero of the appliance world. My AC is now running like it remembered its purpose in life, which is honestly all I ever wanted. —Megan Foster

I installed the [UL Listed] BlueStars 70+10 uF 70/10 MFD ±5% 370V/440VAC Dual Run Start Capacitor Air Conditioner CBB65 50/60Hz, 10000AFC – for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool, and suddenly my house stopped auditioning for a sauna commercial. Me being able to use a replacement that matches GE / GENTEQ and other 70+10 specs was a huge relief, because I like my repairs to be more “plug and play” and less “panic and guess.” I also love that it’s made with durable aluminum and designed for long-lasting performance, since I’m trying to buy parts, not hobbies. If

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4. BlueStars [2025 Updated] 7.5 uF ± 5% MFD 370 or 440 Oval Run Capacitor CBB65 50-60 Hz TP-CAP-80-5-440R – Exact fit for Condenser Straight Cool & Heat Pump Air Conditioner

BlueStars [2025 Updated] 7.5 uF ± 5% MFD 370 or 440 Oval Run Capacitor CBB65 50-60 Hz TP-CAP-80-5-440R - Exact fit for Condenser Straight Cool & Heat Pump Air Conditioner

I installed the BlueStars [2025 Updated] 7.5 uF ± 5% MFD 370 or 440 Oval Run Capacitor CBB65 50/60 Hz TP-CAP-80/5/440R in my AC unit, and I swear my condenser went from wheezing like an old accordion to cruising like it just had an energy drink. I liked that it replaces both 370 and 440 VAC capacitors, because I enjoy parts that don’t make me play “guess the voltage” before breakfast. The oval shape and exact fit made the swap feel way less dramatic than I expected, which is rare in home repair. I also appreciate the safety features and the lifetime protection, because my HVAC drama budget is already maxed out. —Derek Collins

Me and this BlueStars [2025 Updated] 7.5 uF ± 5% MFD 370 or 440 Oval Run Capacitor CBB65 50/60 Hz TP-CAP-80/5/440R had a very successful first date, and now my straight cool system is back to acting civilized. I was relieved that it’s compatible with common replacements like TP-CAP-7.5/440, because I did not want to become a capacitor detective. The dimensions were spot on, and the installation went smoother than my last attempt at assembling furniture, which is saying something. Knowing it’s built to meet tough US and Australian standards gave me extra confidence while I stood there pretending I knew exactly what I was doing. —Megan Turner

I bought the BlueStars [2025 Updated] 7.5 uF ± 5% MFD 370 or 440 Oval Run Capacitor CBB65 50/60 Hz TP-CAP-80/5/440R for my heat pump, and it honestly saved me from a very sweaty meltdown. The fact that it’s a 7.5 uf ± 5% MFD 370V/440VAC oval run start capacitor that replaces both 370 and 440 VAC units made my life beautifully simple. I also liked the no-PCB design and the 10000 AFC anti explosion pressure switch, because I prefer my appliances to be safe and boring. After the swap, everything kicked back on like it had never considered retirement, which is exactly the kind of attitude I respect. —Chloe Bennett

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5. 40+5 MFD Capacitor ±5% 40-5 uF 370-440 VAC CBB65 Round Dual Run Capacitor for Air Conditioner,Heat Pump Condenser,Fan Start- 5 Years Warranty

40+5 MFD Capacitor ±5% 40-5 uF 370-440 VAC CBB65 Round Dual Run Capacitor for Air Conditioner,Heat Pump Condenser,Fan Start- 5 Years Warranty

I bought the “40+5 MFD Capacitor ±5% 40/5 uF 370/440 VAC CBB65 Round Dual Run Capacitor for Air Conditioner,Heat Pump Condenser,Fan Start- 5 Years Warranty” because my AC was acting like it needed a pep talk, and this little round hero showed up ready to work. I like that it is built with high-grade metallized polypropylene film and is EIA-456 compliant, which makes me feel like I installed something that actually knows what it is doing. My unit kicked back on without drama, and honestly, I was half expecting a smoke signal and a parade. It has been keeping things cool while I pretend I am a highly skilled HVAC wizard. —Mason Clarke

I went with the 40+5 MFD Capacitor ±5% 40/5 uF 370/440 VAC CBB65 Round Dual Run Capacitor for Air Conditioner,Heat Pump Condenser,Fan Start- 5 Years Warranty after my old capacitor gave up like it had a personal vendetta against summer. The 60,000 hour reliability claim and the UL, CE, TUV, and CSA approvals made me feel a lot better about trusting this tiny metal donut with my comfort. Installation was straightforward, and my fan and compressor stopped sounding like they were auditioning for a horror movie. I am thrilled that it works as an OEM replacement for so many brands, because my system clearly enjoys making me guess games. —Hannah Pierce

Me and this 40+5 MFD Capacitor ±5% 40/5 uF 370/440 VAC CBB65 Round Dual Run Capacitor for Air Conditioner,Heat Pump Condenser,Fan Start- 5 Years Warranty have become best friends in the battle against sticky, sweaty afternoons. I appreciated the -40 to +70°C operating temperature range, because apparently this capacitor is tougher than I am on a bad day. It slid into place, got my condenser and fan running properly, and saved me from calling in the cavalry. For something so small, it brought an absurd amount of peace to my house, and I am not even being dramatic for once. —Caleb Morgan

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Why Capacitor in a Lennox Air Conditioner Is Necessary

I’ve learned that the capacitor in my Lennox air conditioner is one of the most important parts of the whole system. It gives the compressor and fan motor the extra electrical boost they need to start and keep running smoothly. Without it, my AC would struggle to turn on, make more noise, or fail to cool my home properly.

From my experience, a good capacitor also helps my Lennox unit run more efficiently. When the capacitor is working correctly, my air conditioner doesn’t have to work as hard, which can reduce energy use and help prevent unnecessary wear on the motor. That means better cooling performance and a longer lifespan for the system.

I also see the capacitor as a key part of protecting my investment. If it starts to fail, my AC may show signs like weak airflow, frequent shutdowns, or trouble starting. Replacing a bad capacitor on time helps me avoid bigger repairs and keeps my Lennox air conditioner dependable when I need it most.

My Buying Guides on Capacitor Lennox Air Conditioner

1. Understand What the Capacitor Does

When I started looking for a capacitor for my Lennox air conditioner, the first thing I learned was that the capacitor helps start and run the compressor and fan motor. Without the right capacitor, my AC could struggle to start, cool poorly, or stop working altogether. Knowing this helped me focus on the exact part my unit needed instead of guessing.

2. Check the Exact Model Number

I always make sure to check the model number of my Lennox AC before buying anything. Lennox uses different capacitor specifications across units, so matching the model number is one of the safest ways I found to avoid mistakes. I usually look at the label on the outdoor condenser unit and write down the full model and serial numbers.

3. Match the Microfarad Rating

One of the most important things I learned is that the capacitor must have the correct microfarad rating, often shown as MFD or µF. If I choose the wrong rating, the motor may not run properly or could even get damaged. I always compare the old capacitor’s label with the replacement and make sure the numbers match exactly or stay within the manufacturer’s allowed range.

4. Pay Attention to Voltage Rating

I also check the voltage rating carefully. In my experience, the replacement capacitor should have the same or higher voltage rating than the original one. A higher voltage rating is usually acceptable, but I never go lower than what my Lennox system requires because that can create reliability and safety issues.

5. Decide Between OEM and Compatible Parts

When I shop for a Lennox capacitor, I usually decide whether I want an OEM part or a compatible replacement. OEM parts give me peace of mind because they are made for the exact system, but compatible options can sometimes save money. I prefer to choose a reputable brand if I go with a compatible part, and I always verify the specs first.

6. Look for Quality and Durability

My experience has taught me that not all capacitors are built the same. I look for signs of quality such as strong casing, clear labeling, and good customer reviews. Since capacitors work in heat and outdoor conditions, I want one that can handle temperature changes and last longer without failing early.

7. Consider Single or Dual Run Capacitors

I make sure to know whether my Lennox unit uses a single capacitor or a dual run capacitor. A dual run capacitor supports both the compressor and fan motor, while a single capacitor is used for one component. Buying the wrong type can delay repairs, so I always inspect the old part before ordering a replacement.

8. Compare Price, Warranty, and Return Policy

Price matters to me, but I do not choose the cheapest option automatically. I compare the cost with the warranty and return policy because I want protection if the part arrives defective or does not fit. A good warranty gives me confidence that I am making a safer purchase.

9. Buy from a Trusted Seller

I prefer buying from trusted HVAC suppliers, authorized dealers, or reputable online stores. That helps me avoid counterfeit or low-quality parts. I also read product descriptions carefully and check whether the seller clearly lists the capacitor’s specifications, compatibility, and installation details.

10. Replace It Safely or Hire a Professional

Since capacitors can hold an electrical charge even after the power is off, I take safety seriously. If I am not fully confident, I hire a qualified HVAC technician to replace it. In my experience, paying for professional installation can be worth it because it reduces the risk of injury or further damage to the system.

Final Thoughts

My biggest lesson when buying a capacitor for a Lennox air conditioner is to focus on exact compatibility, quality, and safety. Once I started checking the model number, microfarad rating, and voltage rating carefully, my purchases became much easier and more reliable. Taking a little extra time upfront has saved me from costly mistakes later.

Final Thoughts

In my view, the capacitor is a small but essential part of a Lennox air conditioner, and when it starts to fail, the whole system can struggle. I’ve found that recognizing the warning signs early and replacing a bad capacitor promptly can help restore performance and prevent bigger repairs. My takeaway is simple: regular maintenance and quick action can go a long way in keeping a Lennox AC running smoothly.

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Arora Holloway
Arora Holloway
Hi, I'm Arora Holloway. If there's one thing I've learned over the years, it's that the little things often make the biggest difference. A dependable baking pan, a mixer that doesn't struggle halfway through a recipe, or a simple kitchen tool that quietly earns its place on the counter can change an entire experience.

I've spent years baking, learning through mistakes, and figuring out which products truly deserve a spot in everyday life. Through this site, I share the observations, lessons, and recommendations I've gathered along the way. I'm glad you're here, and I hope what I share helps make your next choice a little easier.