The Main Reason Why Start Capacitors Fail in HVAC Units! This Cap Blows Out!

The failure usually comes from a bad installation. You MUST install the relay with the mounting lug at the top or the arrow up. The contacts are not meant to be installed sideways and will stick closed.

Can you tell me what a grinding noise could be coming from the actual unit inside my home? It's a brand new home!

so what would make the start cap blow but with a good potential relay. this just happened to me.

Great video
Is there a video of how to add a start capacitor to an existing AC that’s having issues with the compressor starting? Run cap is good but it doesn’t have a start cap, thanks

Great video.

👏🏿👏🏿👏🏿beautiful demonstration

You mentioned start and run capacitors are made different. How would I identify a start from a run capacitor?

Excellent video!

It failed because you let the smoke out of it

Aww. It shitted all over itself..

How do you get a free capacitor because it's still under warranty?
Without incurring a service charge from the tech. Company.
If you can DIY and the part is still under warranty, then why can't a company such as Carrier send a new part out, free of charge?
I know the part is not that expensive, but it is still under warranty and it's the principle of the thing.
Many other under warranty, household items and appliances can be requested from manufacturer's, free of cost, without a tech. service visit.
Why should this be different?

Wow what a great way to explain capacitor failure .thanks

great video ..... i just pass my school and got my Universal EPA .... but i am still learning from you ... thanks for great video...

Why do people, even professionals, put start capacitors with potential relays on the condenser unit (hard start kit)? I was going to do the same until I saw the video from HVAC school showing the myths behind hard start kits. Now I’m scared to put a hard start kit on my condenser. I’m hoping some HVAC professional can challenge the instructor from HVAC school and the electrical engineer that they interviewed!

Dummy tech didn't replace that relay. I bet this cap fails middle of summer

Very good

I heard copper grease helps a lot with keeping high amp contacts from sticking.

How long should it take the compressor to get up to top speed?

This is so awesome to see! I had the same fluid explode everywhere. Smells terrible by the way.

Never thought about just popping the relays out and visually inspecting them. It’s so obvious lol

Most usefull video on the internet!
Our A/C guy was just changing the capacitor... When it failed a second time, he said it was time to change the unit!
Turns out the emf relay was busted!
Thanks!

great video bc us techs rarely get to actually see when a Start cap blowS & lets the smoke OUT !!! .LOL ...what a mess , Thanks for all you Do for this industry & us Techs out in the Field

Why research & development is so so critical for an excellent product - Awesome analysis

I’ve watched several vids on how this process works. This resonates better than all of them. Thank you.

I just rewired an exhaust draft hood, and they had 2 motors wired together, running off of two 25uF capacitors wired in parallel , for a needed 50uF to start the motors.
I replaced the 2-25 uF Caps, with a single 50 uF, and they start fine. But I see no information anywhere, on how, 2 motors wired together, using 1 Capacitor (or two, to get the total 50 uf needed), and how you would size such a situation. I tried to see if one motor would start with only one of the 25uF Caps, and it would not. These existing, were rated at 270vac (from Italy). Replaced with a 50MFD at 440/370 and it starts great.

Excellent video, so well and clearly explained and demonstrated.

Do you have electrical tape wrapped around your finger?

Great video sir! Question, why did the relay fail?

Nice video! I just tried to install a hard start kit for my Goodman 4 Ton last week. I hooked it up and after the first start it ran fine and then on the second time the AC started up the hard start cap popped on me. I thought maybe it was abad hard start cap but now I'm wondering if it was the potential relay.

Ayo wtf

So my a/c keeps blowing capacitors. I’m having one installed about every 3 months. For years this has been going on. Literally have spent thousands on this unit. When the ac man comes tomorrow, I’m going to find out if it’s the start or run capacitor and try to fix it myself. I’m willing to bet that thing you mentioned is the reason we keep having this issue. I can do anything mechanical, cars, engines, but nothing electrical. But what you were showing looks easy enough to diagnose myself.

Also have a refrigerant leak but that’s another day and time. I’ve put on average $1000 a year into my unit 10+ years and like clockwork it fails. I could have bought a new one with all the money I put into it. It’s a Goodman btw, don’t recommend them. The unit/house was 6 years old when we moved in and the day we moved, it broke. Been non stop ever since. I know this stuff doesn’t last forever but for the price of it, it should.

Noob here. Is that just SPST relay?

I can't believe this isn't clickbait. Holy shit

I really like how you kept touching the CAP terminals that would FRY YOU if you didn't bleed it down ..

I saw myself accidentally involved in this stuff, I saw a homeless dude once struggling to carry a off-brand chinese portable AC unit, I offered help and he offered me to keep it for 6 $, so I accepted as I needed a porch fan (which are 30$ at least), upon quick inspection the cold/heat mode did nothing and the main fan slowed down at fixed intervals (the compressor didn't its characteristic hum, so I said, well, it's toast) , we have been using it in fan mode for a while and it does its job, yesterday I was bored and decided to peek inside, I noticed the compressor hummed very faintly for 2 seconds, and gave up for another 15 seconds and repeating this power cycle, upon board inspection, no relays seemed to be failing, motors were OK, and symptoms point to this stupid capacitor which is also the reason for good units to be declared EOL and replaced entirely? Even experienced technicians will resort to installing a whole new set... Which still doesn't make a lot of sense to me (money wise maybe for the technician and sellers)

UPDATE I'm done with the installation and it works like new, not thinking about installing it as my house already has AC, but it will be handy to have it around

The original start Cap on my 1991 AC compressor just blew. I was told that modern Caps aren't as good as old ones. Any truth to this and are any modern brands better than others?

I learned a lot from this video. Thanks

Craig, my question is, "Why would a run capacitor blow twice in 1 month?" Any ideas?

Bro im new and you helped me a lot thanks

Can you use hard start on scroll compressor?

What happens if the compressor motor goes into thermal overload (either at start, or after it was running) ? Does this damage the start capacitor?

"uF" is actually micro Farads.

Love your videos! Very clear and easy to follow presentation. You have a gift of beating a great teacher!

Thank very nice information

??? I have a start capacitor that measures greater than 20% over the rated capacity. Rated 147-174 mfd 220-250 v, but reads as 218 mfd. can this burn out a solid state start relay? Thanks!

Exactely today happend to mee .explose starting cspacitore .thnx 4 this information. Ineed change new relais 🙂👍

absolutamente good demostracion !! Thank You good Techs

Craig you’re the excellent instructor of my life I showed, much appreciated for sharing your knowledge with us.

QUESTiON: CAN WE PUT AN OVAL RUN CAPACiTOR iN THE PLACE OF A START CAPACiTOR ON THE AC UNiT OUTSiDE?

Thank you!