So, depending on the part of the country that you live in, you may have a major problem with capacitor failure or not, and we noticed that in hotter states states with higher temperatures that we see much higher rates of run, capacitor failure. Now the first thing about this video - if you don't hear anything else, I want you to hear that this is about run capacitors, so capacitors that stay in the circuit all the time and for the compressor condenser fan motor and the blower motor and run capacitor doesn't Have a relay in it like a start capacitor, and so it doesn't it's not affected by turning it on and off it doesn't have to come out of the circuit at a certain point, like a start capacitor. So a lot of the confusion that I see when it comes to things that technicians think of as causes for failure. They, those are causes for failure for start capacitors, but not for run capacitors.

So the reason for this video is when you have something that fails as much as run capacitors do, especially in certain parts of the country. People want to come up with theories about why they fail and it's important that we know what can cause them to fail. So that way, we can do what we can to prevent it, and also so that we don't tell people the wrong thing. We don't want to tell people that something causes something to fail if it in turn, if it actually doesn't cause it to fail.

So in this video we explore some of the different common theories out there, and so some of the common theories are that if your motor is drawing high amperage, that will cause the capacitor to fail sooner so that there's something that goes on inside the motor itself. That causes the capacitor to fail. Many have said that they notice that a system that's low on charge seems to have weak capacitors or a system with the dirty condenser coil seems to have more commonly failed capacitors. Some people have said, including my own brother, have said that they've noticed that it seems like capacitors fail.

More often when the voltage is low, the applied voltage coming in is low, and so I want to explore this and to start with before we go any further. You have to have a basic understanding of what a capacitor is and the best way that I can kind of get you to imagine. It is think of a capacitor, a run capacitor like a storage tank or like a pressure tank. So if you're used to pressure tanks and say well pumped, for example, you understand that it pressurizes that pressure tank and the amount of water that can be stored in that pressure tank is contingent on the incoming pressure.

So you can't have more pressure on the pressure tank than the incoming pressure coming in and that's how the Pasteur works. A capacitor can store the electrons that are forced into it, but at some point it can't store anymore and that's dictated by the amount of pressure, which is why the amperage of a capacitor is dictated by the voltage applied to it. The capacitance of the capacitor and the frequency, and so first off the bat, if you're in the u.s. frequencies pretty much 60 Hertz now could there be some cases? You know we see capacitors installed in variable frequency drives and whatever, where you have some various frequencies, and so could that affect the capacitor, absolutely it could, but for most of what we do, it's pegged at 60 Hertz and in Europe and other places it's at 50.

Hertz, so if you're hurt stays the same, your frequency stays the same, and your capacitor has a certain capacitance rating. Then the amount of electrons that can go in and out of that capacitor are now just fluctuate based on the voltage, if you think of it, like that pressure tank for the pump, you may can receive electrons and it can store them and then it can release Them that's, that's, essentially how it works and as that phase changes, it's constantly storing and releasing 60 times per second, so we're gon na explore some of these things and see if we can test and prove exactly how this works, give you a better sense of what Can actually cause the capacitor to fail? The question is: what are the things that can cause a capacitor to fail and there's a common belief in the field that there's something that the compressor can do or the system can do to cause the capacitor to fail? But the more that I research it the more we learn that the capacitor has a fixed amount of current that can go in and out of it, and so I want to do some demonstrations here to kind of show what I'm talking about. First measure the voltage and then the amperage off of this test. Oh 770, 3.

291 volts, our start winding. We've got 4.2 okay, so he's got ta. Have that as our baseline four point two amps 291 volts that we've got 212 213 volts. Something like that you, this is just an image of a typical capacitor and then over here we have a kind of an old-school, wiring diagram, and so what we're going to be focusing on is the capacitor.

That's this part here and then this is a dual cap and a dual cap. One side would be the C side, and so the C side would be the side that connects over to the run side of the circuit. So one of the legs of power, the same side of the leg, a power that connects to the runs out of the circuit is the one that goes to the C terminal and then our Herms ID is the side that goes over to the start winding. So, let's establish some things here in order for you to have a potential difference, a difference of voltage between C and s on the start, winding C here we have to have a movement of electrons in and out of this capacitor.

So a couple quick rules here: capacitor electrons, cannot pass through a capacitor. They don't go through one side to the other. They can't there's no connection between the C and Herm sides inside that capacitor there's just an attraction across the plates, so they gather on one side. So a positive charge gathers on one side and negative charge on the other and that it as the phase switches of the incoming alternating current on our lines.

Then it switches back and so what this capacitor does. It adds in a phase shift, so it adds in a 90 degree, phase shift which helps correct for the phase shift that occurs in the inductance of the motor and motor is an inductive load, and so there's this thing called inductive reactance. We won't go into that, but it's correcting, for you know it's creating a unitary power factor and it's helping the motor run in the right direction with torque as we'll keep it really simple. When you have a run capacitor that capacitor has a capacitance rating, so this capacitor here we'll say it's a 45 by 5, but in this case of the compressor it has 45 micro, farad's micro farad's describes how many electrons can be stored and discharged in and out Of that capacitor, so the only electrons that can go through this start winding are ones that can store and the other side and then back again now that can change with frequency.

But, as you know, the typical compressor capacitor, your frequency, doesn't change, and since the frequency is stays at 60 Hertz, then the amount of current that can go in and out of this capacitor are completely dictated by the capacitor itself. Capacitors have voltage ratings on them. We've talked about that, and so if the voltage goes higher than what the capacitor is rated for, then the capacitor can fail, because the electrons can actually bridge either across the two plates or it could bridge to ground and that's a problem. Another thing we know is that the changes in ambient temperature can also affect the life of the capacitor.

Alright, so we've got a 90 degree ambient condition. So it's good and good and warm outside I'm gon na use this K type B probe and attach it to the capacitor and see what we're reading with it running. Normally, I've got the bead probe attached to the K, type K, type thermocouple attached and it's running. Ninety one point six degrees right now, so just barely over ambient temperature she's good and running for quite a while.

Now I set the temperature downs that will keep running I'm feeling I have it connected with alligator clips measuring the wattage and the power factor, and it's showing that I'm at unity, power factor, which means that capacitance is doing its job to overcome the inductance. That's a whole other kind of conversation, but just want to make sure that the capacitor is indeed functioning properly and definitely is sure, everything's everything sighs properly. So now, let's see if we can get the temperature to go up on this capacitor by short, cycling, the equipment all right here we go. Don't try this at home, not good for the unit, I'm gon na short cycle it like crazy all right.

So an interesting kind of unintended consequence happened here that compressors running backwards, that the sounds of it and we get a backwards running compressor now pre-set enough. Yes, oh, this is a pretty new unit and it was only installed three months ago and it's got a Copeland scroll in it. So it's a good good compressor, but yeah. We definitely saw that short cycling caused it to run backwards, which you know when that happens.

In real life, that's not a good thing: it's not gon na run properly. We were only drawing 3.6 amps on common wire, whereas before we were drawing over 7 - and you could hear that sound - it was just not definitely not right. Now, we're back running normally again. Can see so far? No so first off you can see on this graph.

It shows you that the higher the voltage is anything above the rated voltage. It very quickly decreases the life of the capacitor. So if you have a high voltage surge from the Power Company or you have a lightning strike or anything like that in the area, then that's gon na greatly decrease the life of the capacitor you're gon na get bridging across those plates, and it could very easily Cause it to fail, and then, if you look at this next image here, the higher the temperature is the shorter. The life of the capacitor is going to be the lower.

The temperature is the longer the life of the capacitor is going to be. The ambient temperature around what you're, not gon na see is an amperage rating. Well, why is that? Well, because amperage current is dictated by the number of electrons moving through a conductor and that number, through the start, winding is completely dictated by the capacitance. Now some of you may say hey, I know for a fact that I see high ink.

I see high current on a compressor when it starts up, so I think a locked compressor can cause a capacitor to fail. I think high current can cause the capacitor to fail so you're reading on the common lead, the lead coming from the common terminal, a common isn't a winding. It's just a point in between run and start. So when you read current uncommon, what are you reading you're reading run and you're reading start you're reading their current on both of those lines right, if you were to just measure on the start winding, though, do it sometime? If your meter has an inrush feature on it, put it in in rush mode and measure, your start, amps and you'll notice that your start amps with a normal system that only has a running capacitor and not starting capacitor or starting capacitors.

It will not draw high current. You will notice that when you have a start, capacitor in place and a potential relay that initially when it starts up, you will have high current on the start. Winding. That's expected because the start capacitor only stays in the circuit and the start winding for the first couple, milliseconds until that compressor gets up to 80 percent of its total speed.

So that's going to happen very very quickly, I'm in the first fractions of a second. If you have a meter that can do this, that can read that in rush amps, then you will see a higher start reading when it starts up, and that's only because you have the additional electron capacity of these capacitors in the circuit. If you don't have this whole, you know set up in here, you don't have a start capacitor with a potential relay and you only have a run capacitor then your amperage on start and run are going to be the same because your amperes are dictated. I, the number of electrons that that run capacitor can hold experiment, sometimes put in a smaller run, capacitor smaller than it's rated for and measure your start winding.

Amps then put in a larger run, capacitor and then measure your start winding. Amps you'll notice that when you put in a larger capacitor, you have more amperage when you put in a smaller capacitor, you have lower amperage, so the amperage of your start winding are completely dictated by the voltage and by the capacitance. Now some people will point out. Well, your motor does add inductive reactance when you measure in between these two points between start and common, you see a much higher voltage than the applied line voltage and that's because of the back EMF that occurs within the start.

Winding its back electromotive force, your motor actually acts like a generator as well and actually generates a higher voltage, but again the highest voltage that your motor is going to generate is when it's up to full speed. That's not going to be during starting and much of the things that are attributed to failures in a capacitor or when people say well when the motor has a hard time, starting or when the systems short cycling. Then that causes your running capacitor to fail now high ambient temperatures can cause you're running capacitor fails. So if the unit's getting hot, you have a failed condensing fan motor or something like that, then that can cause it to fail prematurely and then also high voltage conditions.

Can cause it to fail prematurely or if you had some, you know higher frequency or something that could cause it. That would be extremely abnormal, but, with all things being usual, the only things that can cause a run capacitor to fail are high voltage, high current or a run capacitor that is poorly designed, poorly executed, poorly manufactured, or it's just at the end of its life. I mean so everything has a life expectancy over time, but that's the reason why I'm a big fan of the mrad capacitors, because we've seen that they form more to spec than some of the other ones that we've seen. We see that they're they're very well made faster, so that's it.

What can cause a a run capacitor to fail? Well, the only thing in causes to fail is higher voltage, which also could lead to higher. If you have higher voltage than you will have higher amperage on your start, winding higher than designed voltage or higher than design temperature or just higher ambient temperatures over a longer period of time will also cause failure. Alright, so let's try it again, I'm going to try to give it a little more between my cords, I came now we're going to test in rush amps on the start winding and show the difference between in rush and full load amps on the start winding verses. The runway alright, so this is our regular running amps.

Our start winding coming from our capacitors. So that's connected to her connected to her am rad turbo 200. So it's connected to 45 micro farad's. I'm going to go ahead and shut it off and then I'm gon na put it on in Russia.

There we go in rushing amps, so now, let's see what we get on startup. Let's try it again just to see if there was something weird going on there. Amps it's currently off in rush there you go in rush amps, let's see what we get nothing alright, now we're gon na, try it again on the common of the compressor. Actually, let's do it.

Let's do it on run just so that we're, because what I'm wanting to show you is that it's run that sees that in rash, not start. No, that's it in rush, so this is on the run winding of the compressor. Here we go alright, so there we had an inrush of 60, so no inrush on started all didn't even log it and that's because on the start winding the capacitor inhibits the amount of current that can flow through the amount of current they can go through. The start winding it's completely dictated by that capacitor, because electrons aren't allowed to move actually through the capacitor.

They can only go in and out of the capacitor. So the capacitance dictates that and see here still at 92 degrees, even after all, this monkeying around and short cycling that I'm doing what you see uncommon is start bus run right. So you get that so, let's now measure the inrush amps on common to help. Additionally, prove that the all of the inrush is on run and not on the start winding in rush all right now.

Well, would you look at that common and run show the same in Rush and start doesn't show an inrush at all. So if we have a locked compressor that capacitors not gon na see that increase in amperage, that increase in amperage is going to be seen on the run not on the start. In some cases, you're gon na notice that your run wire is connected not back to the contactor but actually back to the capacitor. So in some cases your run winding isn't going to go to the contactor it's going to go to the capacitor and then the capacitor acts as the junction point.

In that case, you will get additional heat because it's using the capacitor as a connection point to make connection for run in this application. Here your run winding goes right back to the compressor, there's right from the contactor to thing compressors, so any heat that's built up is gon na be built up through here. It's not gon na go to the capacitor at all. If you look here, we've been messing around with this thing for a while now and our temperature of our capacitor is not increasing.

When we talk about amperage, we're always talking about amperage on common, that's where we measure it, and so the assumption that a lot of technicians have is that when you see an increase in amperage on common that that's going to equal an increase of am and amperage On start, but the thing that they miss is that the amperage on start is dictated by the capacitance of the capacitor and the incoming voltage higher voltage is going to result in higher amperage on the capacitor and the capacitance of the capacitor is going to result in Higher amperage on the start, winding of the capacitor, some Tech's get confused. They combine together the concept of a start capacitor, which has very high capacitance and thus will have a lot of amperage on it. But it's supposed to be taken out for a short time, with a run capacitor that is always in the circuit or on capacitor, never comes out of the circuit all right, so this may be another way. That's kind of helpful to you to understand what I'm talking about, because the thing that techs have a hard time getting their head around is the fact that the capacitor is what dictates the amperage on the start winding.

This doesn't seem right because we just imagined that somehow electrons are coming through one side getting boosted up and then go into the compressor. Like that's how a lot of texts imagine this, and you got to get your head around the fact that that's not how it works at all in order to help this make sense. What's actually happening, is you have a current, that's gon na travel through here and then go to start? Is this common and then it's going to go through to start store and then release back the same direction that it came from and that's what creates that phase shift? And then we also have a higher voltage applied on it because of the back EMF from the motor and so in this example. This is how to test to run capacitor under load.

It's on the resources, tab of HVAC, our school comm, and so here you can see we have an applied voltage across the capacitor of 292 point nine from here to here and then we have a compressor start wire, seven point: eight! This is actually a real unit. I got these readings off of, and so if we want to find the capacitance, we can use these live readings right well. How would that work if this amperage wasn't completely dictated by the capacitor and the capacitor size and the voltage you understand that it wouldn't work? The amperage, the voltage equal, the capacitance and that's how we do it. So we take the amperage 7.8 amps.

We multiply it times, a constant 26:52. Some people use 26:53 or 2650 makes the very little difference. 7.8 times 26 52 divided by the applied voltage equals the capacitance you'll notice. It doesn't know we're on here.

Are you taking the amperage of the compressor other than the start wire you're, not taking the run wire? Amperage you're not taking the common wire amperage you're, not measuring the applied voltage earning that stuff. You're literally just saying what is the voltage applied to the capacitor and once you know the voltage applied to the capacitor and the amperage, then you can determine the micro farad's of that capacitor under load, which indicates to you that it's the capacitance and the voltage that Dictates the amperage that the compressor is going to draw on the start winding. The only way that you could have higher amperage on this start winding is, if you had higher voltage or higher capacitance, and the voltage increases above the applied line voltage based on the back EMF that comes from the motor, which only happens when the motor starts to Speed up so that tells you that if anything, you're only have a run capacitor in the circuit that, if anything, your amperage will be lower on your start winding when it starts, then once it starts running, because that back EMF only comes up, this voltage only increases Once this motor gets up to speed all right, so let's do another quick demonstration, so a lot of technicians. You know that this is a run, capacitor right or something real, quick, there's no relay in this.

This is constantly in the circuit when it's, when it has voltage applied to it when it has potential applied to it, a lot of confusion between a start capacitor, which has a potential relay that takes it out of the circuit and a run capacitor, which constantly stays In series, with the start winding of a motor okay, so this stays in the circuit all the time. Let me ask you a question if I take this plug and I plug this into 120 volt source - and I connect it to this capacitor, what's gon na happen. Well, some guys think I've asked a few and some think it'll do nothing. Some think that it will be a direct short and so, let's show exactly what happens when get in that way.

So this is a turbot tuber, 200 mini I am, and so it has a five two point: five and a 7.5, so we're gon na go for the 7.5. We're gon na go for the gussto here 7.5. Is the brown then we're gon na connect this to the center I'm gon na put on my gloves my glasses, so that way here it remember what you think is going to happen first and then I'll show you what does actually happen and rather than showing you The voltage I'm just going to prove it to you by showing you the amperage on this wire. Look at there things drawn half an amp drawn.

Half an amp, how's it drawn half an amp. Is it actually creating any heat? Is it doing any work? The answer is no, it's not. That is all reactive power, which means that it's creating and out of phase. So it's storing and discharging it's taking from where it came from and then putting it right back again.

That's what a capacitor does. If you imagine almost like a balloon, fills up and then discharges fills up in the discharges, that's sort of what it's like, but there's no actual connection in between these terminals. These two terminals aren't shorted. Together, you have a plate and then you have a magnetic field or an electrical field that builds up on either side of the plates that attracts and then repels the electrons in and out.

So this thing is like a little electron balloon. That's just constantly filling up in discharging filling up and discharging there's a differential charge across those two terminals. What will happen if I apply a higher voltage to this well? First, before we do anything else, I want to show the temperature of this capacitor with it unplugged and then let it plugged in you can see we're unplugged. Here, I'm going to go ahead and discharge the end of this, because right now, there's actually a charge here again.

This is the correct way to discharge your capacitor with the discharge, which is 20,000 K, 10 watt resistor that I have connected all right so thick. I measure the temperature first, let's take a look at the ambient right now when the ambient temperature actually went up quite a bit, we're 95 degrees right now outside, so we're gon na use this Cape type heat probe, the actual temperature of that metal is below the Outdoor ambient, I just brought it in from outside, so we'll, let that stabilize for a second see what we see what we end up at now. One thing to know about these is: these are rated at over 150 degrees, Fahrenheit, so regular ambient conditions shouldn't cause these to fail, but what we do know is is that increases on ambient conditions can cause them to fail earlier than they would otherwise. So it's not like being in a hot temperature environment is going to make it fail.

But what will happen is if you're in a higher temperature ambient environment, it's not going to last as long all right. So we've stabilized here at 86, 0.9. Now, let's go ahead and plug it in so we're gon na have some current passing in and out of it you actually now have electrons going in and out of this capacitor, I can prove it there. You go get electrons going in and out of this capacitor now the reason why these capacitors have metal shells they have oil inside of them and that oil helps keep them cool as as electrons are passing in and out, because there is some heat generated as those As those electrons are moving in and out of a capacitor and because it's always in the circuit never comes out, it doesn't have a relay that takes it out.

It needs to have something to keep it cool now over time. It will slowly increase in temperature, but with the oil fill and the amount of load that I'm applying on it right now, it's not going to increase any significant amount of I've actually tested some of these before. Obviously it's going to increase in temperature because the outside is warmer than 87. So now let's go ahead and apply a higher voltage to it.

I have it connected to a disconnect section 208. So it's gon na be about 2, 13 volts, 1. 13 volts right now. Our temperatures been rising because it's hot outside so right now, it's 88 point, seven degrees, it's kind of hard to see what the glare but 80 89 degrees see.

If the temperature keeps increasing right so now we're gon na check the amperage. You can see the amperage went up with the voltage so as the voltage goes up, so does the amperage now make sure you the voltage that we're seeing on it you'll notice that the temperature - it's not really going up just the capacitor doing its job 213 volt Supply to Cross Fit capacitors, not heating up just got power going in and out of it, because that's how a capacitor works. It wouldn't really matter. If I connected a motor to it or not, that's not going to change what it does other than the voltage.

The back EMF being applied from the motor. So if you measure that applied voltage across those terminals - and you know the capacitance of the capacitor, then you're gon na essentially know the amperage. You know what it's going to be, if you think about the capacitor equation that we use for calculating capacitance. It's you take the amperage right of the of the start winding you multiply by 26:52 and then you divide it by the voltage and it gives you the capacitance of that capacitor it's in the 60 Hertz application, and so if you work that math any other way, You can see that if the capacitance is known, if you already know what the capacitance capacitance that the capacitor is - and you know the voltage and you already know what the amperage will be, what that tells you is: is that starting up a motor or basically anything That motor does that's not going to affect the number of electrons that that capacitor can hold.

Oh, the only thing that will affect it is the voltage and so as a motor ramps up that's when the back EMF comes into play. That's when you get that back. Electromotive force, you don't see that back electromotive force until the motor starts to speed up and so a motor, that's short cycling or that's having a hard time. Starting is not going to cause a capacitor to have more current, and without that, how could the capacitor heat up the only thing that can cause the capacitor to heat up our external conditions like if you have a run terminal, that's also connected on the c terminal Of your capacitor and then that's a point of heat or if it's in a hot environment to begin with, for example, if you have a condenser fan motor, that's failing, and because of that, your entire condenser is running hot.

Well then, your capacitor is going to run hot too because of the increased ambient conditions increased temperature around the capacitor. So what we know is increases in voltage caused capacitors to fail prematurely and increases in ambient temperature caused capacitors to fail prematurely. So the cooler you can keep the capacitor and the more you can keep the voltage near its rating or you obviously below its rating, then the better it's gon na last. If you get that voltage above its rating, then you're gon na start getting bridging it's gon na actually say some of the electrons are going to start to bridge and they're gon na start to damage the internals of the capacitor alright.

So hopefully you found that helpful. A couple things that I want you to know about these run capacitors and how they're tested they're tested to last for 60,000 running hours. It's not cycles because in a run, capacitor they're in all the time there are no real cycles. That unit goes on and off, but but you know, you're cycling sixty times per second anyway, you know your voltage.

Your sine wave is going up and down 60 times per second anyway. So turning it on and off, isn't the issue? It's how many running hours does it run and sixty thousand hours is a long time it's somewhere between. You know ten and twenty years, depending on what part of the country you're in it's a long time of running typical air conditioner and there's tested, so that they should work fine up to 70 degrees Celsius for sixty thousand hours, not seventy degrees Fahrenheit. So that's 158 degrees Fahrenheit case in point under normal operating conditions.

Capacitor should last a really long time if they're keeping their manufacturer rating if they're actually tested properly and made properly based on the several different standards. But that's the or the old u.s. Tecumseh's standard is the sixty thousand hours at seventy degrees Celsius. So there's four things that I've identified that can cause run capacitors to fail.

The number one most common is over voltage and we call these transients. That would be power surges. A lot of them are caused by lightning down the line from the power company. The best way to help reduce transients the best one that exists right now is using a good quality surge suppressor using a you know like not not a cheap, you want a good quality surge.

Suppressor is the best way to help prevent those problems with your capacitors, because those are gon na help kind of take those voltage, transients and shunt them to ground before it gets to your capacitor and again in theory, and it depends on the there's a lot of Different factors when it comes to these surge suppressors of whether or not they're going to be effective in actually doing that, but even small spikes and voltage can cause a run capacitor to fail, especially as they accumulate over time because run capacitors. They fail small little sections. Get burned out and then eventually you'll have massive failures. So when you see a run paster where it's getting really weak, that's what's happened is that segments of that foil on the inside segments of that metal coating have melted off, and so you reduce the capacitance over time and you'll see that quite often but the term For the type of search oppressor that I recommend is a thermally, protected metal oxide varistor.

Are there better ones out there than that there are some industrial grade surge suppressors that are going to do a little better, but a thermally protected metal oxide, varistor surge suppressor installed properly with a very short ground on it is the best bet that you're gon na Have to protect against these over voltage conditions that are coming down the line now some people have asked, can the back EMF from the motor be too high, and can that cause it now? The answer to that is not really I mean you could have a motor that produces slightly more back EMF because it's running at a really high speed, an example would be. You have a motor like a compressor, that's under a really low load, and so it's spinning faster and so it's generating a little bit more back EMF, but that still shouldn't be enough to take it over the voltage rating of that capacitor, most capacitors. We work with and the air conditioning side are 370 or 440 volt ratings. It's gon na be pretty rare that you have a voltage failure because of back EMF coming from the motor, because, again, a motor being under greater load because it to run slower will result in less back EMF, not more kind of nerdy stuff.

But some people have asked that question really what it comes down to is the applied voltage down the line, getting transients getting voltage, spikes down the line and reducing that will help increase the life of a capacitor. The next thing is the temperature of the capacitor. Now, like we mentioned here, the lower the voltage is applied to the capacitor, the longer it will last, even when that voltage is decreased below its rating, the further below the rating. You are the longer the capacitor will last, which is why 440 volt capacitors last longer than 370 volt capacitors, even if the applied voltage never gets close to 370.

The same thing is true: with the temperature, the cooler you keep a capacitor the longer it's going to. Last now some people have mentioned that some capacitors are mounted in the air stream, and so when that air stream is higher temperature, it's going to increase the odds that that capacitor fails. The temperature of a capacitor can increase because of all the different types of heat you could have conduction you could have radiation, you could have convection. All of those things can transfer heat to that capacitor, and so, when you have a capacitor, it's in the condenser Airstream or it's exposed to the condenser.

If you have a really high condenser temperature because of a dirty condenser that could increase the temperature of that capacitor and again anything that increases the temperature of the capacitor will reduce its life. That doesn't mean that it will necessarily make it instantaneously fail because again, they're designed for 158 degrees Fahrenheit. It's unlikely that you're going to get into that range. But it's something for you to at least think about that.

That is possible and if you think about some things like a like a heat pump, for example, with a blower capacitor inside the heat pump, it's mounted next to the blower. You will have cases where that that air can start to approach that temperature anytime. You have higher temperature ambient conditions that that capacitor is exposed to whether it's through radiation or conduction or convection, then that capacitor life is going to be decreased, so we've got over voltage, we've got over temperature high ambient temperature can cause it. We have installation considerations, and so you want to install most capacitors upright, and the reason is is because there's a little bit of a void inside that capacitor, where there's no oil and if you flip it upside down, part of the capacitor windings can be exposed to That void versus when you have it right-side up only the terminals are exposed to that void.

Now it depends on the capacitor manufacturer whether or not that's the case. A lot of people have mentioned that a lot of manufacturers place them sideways or upside down. I'm not gon na pass judgment on that. I'm just telling you that it's a known best practice to mount capacitors right side up.

Another thing is how tight the terminals are on the capacitor, so the terminals need to be snug on the capacitor. The other thing is, if your run winding is using the capacitor as a junction point to get back to the contactor. That's also a point that can cause that capacitor to get hot, especially if you're having issues with the compressor. So if the compressor is short cycling or something like that and you're using the capacitor as a junction point as like that is connecting to that C terminal and then back to the contactor, then that can also result in high temperature of the capacitor.

Because that terminal is going to get hot, so you want to make sure it's mounted right side up. In most cases, you want to make sure your connections are really tight and when we'll bring your unwinding connection, your unwinding wire right back to the contactor versus taking it to the capacitor and using the capacitor as a junction point. And then, as it relates to all the other system, conditions that could potentially cause it, I can't see any reason why under voltage can cause it. I can't see any reason why all these other system conditions can cause it other than if the system conditions make the condenser a higher temperature, which then causes the capacitor to be a higher temperature.

I said we've done a lot of testing on this. Hopefully, that's helpful to you gives you some things to look for, and maybe some things to do about helping to prevent capacitor failure. But the biggest thing you can do is use a high quality capacitor. That's why we use imrad and the turbo 200 it's american-made and they do a really nice job testing it.

Alright, thanks for watching we'll see you next time.