We're talking about when you go to a service call and you diagnose a failed compressor and the process of diagnosis surrounding that, right? So it's uh, we're quoting a lot of compressors. We're seeing a lot of compressors quoted and not a lot of other like notes about the system or quotes related to the rest of the system. Compressors generally are made pretty Hardy It takes a lot to break them is what I'm saying. It takes a lot to actually break down a compressor a lot of time Heat Acid or electrical issues to cause a compressor to fail.

So when we have a failed compressor, what should we be asking ourselves what killed this compressor and then three question marks? You've got to make sure you ask those three question marks. Yeah, you got to be like, what in the world, How's this possible? Acid: Okay, acid is one of the number one compressed Killers out there compressor killers. It: uh is also the number one cause for the second compressor death. So you replace a compressor and the second one dies.

The number one cause is acid. Anybody know what? What causes acid in a system Moisture? Yeah, anybody else anything else. Yeah. Moisture: Okay, I'm hearing a lot of moisture.

So moisture cause it causes it because like Fortune a refrigerant. you have the Poe oil. the polyester oil. So moisture in the system interacts with the oil and it becomes a form of acid.

And then that breaks down your compressor's ability to like. Over time, it breaks down the compressor's ability to Loop the oil's ability to lubricate the compressor and keep it running smooth and clean. So yeah, moisture is a big one, but that same moisture and acid also cause or help contribute to those aluminum foil leaks. Yeah, so it can break down aluminum coils as well.

Yeah, close your vacuum. Yeah, so let's get all the moisture out. But where what I want to focus on today is when you show up and you're diagnosing your compressor. We need to be taking steps there to address the whole problem right? We're not just quoting a compressor when you diagnose a compressor.

it's kind of a it's a fun sort of like diagnostic hit. Often it's a it's a big failure. You've just proved something you've shown that you're a technician. You gotta win.

Maybe this is going to turn into a system sales That's exciting, but we need to slow down right there and answer this question and run through whatever we can to figure out what what killed this compressor. So another thing that causes acid is high heat inside the compressor. So your your oil your compressor oil will deteriorate with high heat. So if you have some scenario creating really high temperatures like impacted clog condenser coils I mean it's running at a really high temperature.

It can break down the oil over time. Or when you have a burnout like a compressor burnout or electrically there's a burnout in the compressor, that really high heat moment in there. Um, can actually cause your oil to deteriorate. You got the oil in the system that actually needs to be removed because it's gonna be an asset at this point.

it's going to cause damage to your next compressor. Okay, so what do we do if a system has acid? Or how do we know? Let's start with there. How do we know if a system has acid? Yeah, we have asked. different kinds of acid test kits either on our van or here available at the shop.

You said different kinds We do. There are a couple different kinds out there, but they all do the same thing. They test for acid. Well, there's different kinds of acid we're testing.

No, no, no, no different formats. Yeah, I'm sure there are different kinds of acid. you should test more, but with what we're working with for 1080 refrigerant pretty much exclusively. Yeah, so uh, what are some other like clues that you have acid in the system? You guys have experienced this.

It's taste. It's smell. Won't go with smell. we're going to focus on smell.

Yeah, you often use can Like you're taking off your hoses and that smell of acid and it's like that burning like you know. Ouch. How do we fix an acid problem? s accumulator, compressor, suction line dryer. Yep, it requires a second trip.

acid flush acid away, some sort of acid treatment. and so when you are diagnosing your compressor, that's kind of important to know before you're sending a quote right? What we will often do is replace the accumulator because that's where oil will gather in the bottom of a accumulator right? and so you can't always get all of that out. If you're worried about acid in the system, it's best to quote just replacing the whole accumulator to whereas on a normal Compressor replacement you can typically take that and dump the oil out but you're never going to get it all out if there's acid in there. just quote to replace the accumulator, get damaged or anything like that or no like Ronnie said, you can contribute to a coil breakdown.

So if you have a aluminum coil like you need to be thinking about leaks so which will be our next would be is if you had like acid compressor failure and maybe it's like the original coil on uh mid-aged when I was like eight-year-old Linux to be pretty much guaranteed that if you do a out of warranty thirty seven hundred dollar compressor there and you know the system has acid, well that coil is probably not too. yeah so you you kind of want to keep that in mind if you're going to be quoting larger pairs like that like yeah, the system does have acid you could see it could come you know, coil failure in three months and then hit our guts right? Would you do it the other way too like if you found a leak in a coil because you were low. Would you do an acid test just like out of hand to see if it? If you have one, it never hurts to do an acid test, right? Yeah, I Mean typically you're gonna if it's through the whole refrigerant system like that, you're going to smell it typically and that's another point on burnouts. Sometimes like it's the oil has been turned to acid, but the compressor didn't run after that burnout event and you go to cut open a compressor and then all of a sudden it's really strong.

Like you can smell it. There's definitely acid in the system and you have to stop and take some of these steps. Whatever. our quote would allow for whatever we've quoted to actually make sure we're not going to be out there replacing a warranty compressor in nine months? Yes.

and also installing a suction line dryer. Um, you notice on the suction line dryer there's only a one-way Arrow So I Always want to mention to people when you're installing a suction line dryer, it needs to either be inside where the refrigerant is only going to flow in One Direction So between the reversing valve and the compressor It's Only One Direction there or it's in summer and you know we're going to be back in 10 days. You put it outside on the suction so we can pump down instead of recover the whole refrigerant when we come back. So that process is, We install a suction line dryer and it picks up contaminants in the refrigerant and over the next week.

10 days, two weeks. Something like that, and then we come back and we cut it out. And best practice would be actually to just install another one and leave it permanently in the system. And then, but that one that is full of contaminants, possibly other bits of acid that were throughout your system, Maybe sitting in a coil in a low spot in the suction line.

Things like that, picks it up. So then we take that line dryer out, replace it, leave another one in there. Be best practice that all needs to be thought about when you're quoting that. Repair that test, And in that way, Buddy actually has all the information he needs for sending that quote.

Yeah Usually 10 days to two weeks and then you replace it with another suction line dryer would be best and just leave it. But if it's a heat pump, you can't just have an external suction line dryer. We were just talking about that. It's only one one directional flow, so you could put it inside the condenser permanently and leave it in there once you had replaced that one after 10 days.

That's a way you could do it. but we're not leaving any suction line dryer in our suction line because in the winter that suction line turns into a discharge line flowing in the opposite direction that this filter is designed to go. And if it doesn't completely destroy that filter, break it apart and and knock it through the system, it will blow out whatever it's caught throughout the years and into the rest of the unit. Airflow Considerations: How many times have we quoted a compressor and found things like this on the job right? More than once.

More than once. How many times have we gone back to replace a compressor? and we did that and we turned it on and things look awful when we walk through the house. We find stuff like this. Hopefully never.

But no, we have. That's why we're having this class because we can't. Uh, we can't be replacing a compressor with a coil that looks like this, right? without addressing that problem. When your compressor goes out, how is it? The airflow might have affected the death of that compressor.

Okay, so you have the condenser coil here. Slam Dirty. High temperatures, high pressure. A lot of strain on that compressor.

so you should be looking at those coils and making a part of that process. Cleaning it when you're replacing that compressor. If you see dirty coils and it hasn't been quoted, you're still going to replace it. You're still going to wash those coils, right? I Said replacement wash I Remember replacing a compressor and finding a second filter so they had one in the nice ceiling spot and then right under the unit.

Another hidden filter that was slammed dirty. So the compressor had failed and for years they had replaced just the primary filter. Check for issues with the rest of the system that might have caused that compressor failure. Dirty coils, dirty filters also.

what? What are some other things for airflow? Yeah, for airflow that could cause issues. Giving you some hints here: Duct work issues, crappy ductwork issues, right? Everything is blocking a return. Anything that's going to cause low airflow could create a slugging situation. So like if you don't have enough heat on your coil, you don't boil off all the refrigerant.

The heat comes from the air. So if you have an airflow issue then you're not. You potentially are not boiling off all the refrigerant through these run times. You combine that with a home where the customer likes to keep things cool in their house.

Now we have even less heat to work with. The compressor has these long run times where liquid is making it back into the compressor and it that can cause two problems. It can turn off and the liquid more liquid will kind of migrate and accumulate there and you have that start where the compressor tries to start and it's just hitting liquid which can destroy a compressor. Or you could actually have long enough run times where liquid fills up the base of that compressor and gets to the point where the compressor is attempting to compress liquid and liquid doesn't compress well.

Liquid will destroy a compressor instantly. So you do have some wiggle work room if you have an accumulator or the base of your compressor to fill up with liquid before it actually starts compressing it. But if you have a situation where really poor duct work is contributing, you have a systems freezing things like that. That could be exactly why the last compressor failed and we need to address the whole problem before we come back.

plug in our compressor, turn it on and we have this crazy low suction pressure and temperature. and now the customer finds out they need to replace the ductwork under the trailer. you know, and maybe that would have influenced the whole decision in the first place. With a system something like that, those things are really important to know ahead of time.

On the airflow side of things, we'll have to look out for damper systems. So if you're on a unit that has a damper system, go through and check your zones, check your airflow, make sure there's opening and closing properly. Same same thing, it's good. I Erased damper systems and put clog condenser on here I Would say a thing to remember too like it's a very good.

Let's say you have a failed compressor and you're like man, their coil looks really bad. I Can't quote a coil and a compressor that would destroy their budget? Who cares? Like they need to know the whole truth? Yeah, it's very good. You have to go in and like tell everything in your mind. even if even if you're going to give them a quote, that's like eight grand and they're never going to go for it.

It's like I'm not getting a call back. Couldn't sell the system. Leave them better off anyway. So yeah yeah, our job is to be a technician and and not to actually be to worry about their budget and their decision making for their home.

We just need to give them all the information that's relevant to that unit. And be honest. yeah, don't shy away from doing your full job. Some Refrigerant Things to consider when you find a failed compressor could be low on charge.

How would low on charge contribute to a failed compressor? Yep, Surprise Refrigerant To cool it down. It's running hot. It requires refrigerant cooldown compressors. Our refrigerant cooled you run not only hot, but you also have a lot longer run times.

How could you maybe find low refrigerant if your compressor has failed and you can't run it? That's right, let's see what it is, but if you don't know what it should be, it doesn't matter what it is. Refrigerant Slider Yeah, so you need a PT chart, refrigerant slider and what temperature should be here? Yep, saturations ambient that's inside outside. sort of a combined, but the majority of the temperature that's going to be affecting your refrigerant is outside because that's where most of your refrigerant sits right? Um, but you know it's affected a little bit also by inside temperature. If the blower is running and it's 90 degrees inside, you'll be slightly higher.

But yeah, you usually can just compare it to outdoor ambient temperature and that's the saturation temperature that you should also have on your refrigerant. Now, if you're just slightly low, you're still going to have a pretty normal saturation temperature. It takes a significantly low system, but it's also a pretty embarrassing Miss for a technician who comes back with their compressor and they what's the next thing on the list. They weigh out the refrigerant and there's only three pounds on a seven pound system.

So that's another thing. when you are actually coming back to do the the compressor, weigh the refrigerant out. Because you do need to know before we start this project before we braise in this brand new compressor. if we're low on refrigerant, so weighing it out you might be a pound off if you've done a full recovery and The Purge cycle and you watch your system and it doesn't really come up after that point, you know you've got all the refrigerant out.

But yeah, always weigh out your refrigerant to know what's going on. doing leak testing. So this is what Matt has brought up several times in this class and he's very passionate about Because he's been burnt on before, he's had to do compressors where there was leaking evaporators on the inside. I Think we all care about this, but when you are quoting a compressor typically the age of your system, you should also be going inside and doing a quick electronically test on that coil just to see if there's any leaks.

At least looking at the history to see. you know maybe we've replaced the coil. How old is this system? What's been done here? Maybe a TXV has been replaced in the past? Is there a reason for us to think that there's issues with this system? But yeah, a leak test is a 10 minute thing you can do on an evaporator coil. Electron Elite Test before sending a quote for a compressor to save us a complete Nightmare on the back end, showing up with a compressor not being able to pull a vacuum.

so we have a leaking coil right? we're in. We need to be ready to do a full test after we start up our compressor because it could have been a refrigerant flow issue TXV Something like that that actually caused the last compressor to fail and there's not a way to test that beforehand and those can be difficult conversations. but you know, just stick to the facts. your compressor was not running, but now that it is running, we see that the txt probably contributed to its failure.

So we got to take care of this now. and that's something we want to take care of same day if possible, as fast as we can, that sort of thing so it can be. mentally. It can be very difficult to think about finishing this project and to have that like I'm finally done.

Let's test it out and Boom! There's a problem that can be one of the hardest things as a technician, but again, that's what we are. We're technicians find a way to assimilate the best that you can a normal day and you'll see major problems at a minimum. Okay, electronic issues that take out a compressor, capacitors, and hard starts. Don't quote a compressor if you haven't and then walk away if it has a hard start kit and a capacitor that you didn't check right? how would you start? Uh, check a hard start if the compressors failed or take their Mfdr all night.

Yeah, MFD is about all you can do on that. So good practice. Hard starts failed or compressors failed. We're replacing the hard start kit with it.

The factory hard start kit right? If it's a factory hard start kit, If it just has some hard start kit on there. we're not putting a new one on with a new compressor, but if from the factory, they recommend the hard start kit then we're replacing it with a factory hard start kit. When we're coating the compressor, what else? Electronically, you need to be really looking at that and thinking about it. Another good practice is to just replace the contactor when you replace the compressor.

But at a minimum get used to looking at what could have caused that compressor failure. Things like pitted contactors. it can get stuck, melted in place, the compressor runs continuously, or just that short cycling voltage drop across it that all those things take out a compressor. Wire damage.

how could wire damage contribute to a field compressor? Yep. so you have exposed wires that can create a short where it runs all the time. Or I Also have here short cycling. You can have wires that are causing short cycling with either their poor connections or the short is happening enough to chatter your contactor bumping the float switch after maintenance while the system's running.

Yeah, things that cause short cycling. So if they have a float switch design that pops straight out without a trap and your compressors failed often, I'll just be dumping water just to be looking in that pan and stuff. If maybe the water level has been at the level that flow that would cause that float to be like to to have been shattering, causing short cycling for the system like an inline or just straight out of the pan. Yeah yeah yeah.

Both of those things could cause short cycling and your compressor repeatedly running backwards. All right. School Compressor will do that. Not good things like this low voltage picture I have here.

Um, could be this type of stuff that you want to throw in with your quote. Any like Improvement things you can do on the system that are going to be long-term really good for this customer. When you're doing something like a compressor, you can add several minor things that completely improve the system and also prevent stuff that maybe you didn't realize that could have caused it like this. low voltage picture here could have caused chattering, contactor short cycling, that sort of thing, right? So when you're going to a compressor, when you find a compressor failure, look over your entire system and look for anything else.

One other thing in general, just good practical advice with conversation with the customer. Let them know when you found the reason for failure and when you haven't found the reason for failure, let them know like this is: it takes a lot to take out a compressor. Don't really know the story here I've checked everything I can, but it's possible we have a refrigerant issue. We couldn't know that until we get it running.

so letting them be aware of the full situation that's important. If it's acid, you know what's going on and they need to have that conversation. Their Compressor replacement is going to be a lot more expensive than maybe they've expected or what they Google online because now we have acid protocol. So having that conversation it also sets us above competition if they get a second estimate and no one mentions acid right? we've already mentioned that we've quoted for we have it part of our process, so just be thoughtful with your customer interaction as well.

And last but not least, Don't force a system cell with compressor failure. We are happy to make money doing a repair if that's the decision that they want to make and we're good at that and we're set up to do that well as a company, so make sure you give them their full options. Thanks for watching our video if you enjoyed it and got something out of it. If you wouldn't mind hitting the thumbs up button to like the video, subscribe to the channel and click the notifications Bell to be notified when new videos come out.

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