Noise Complaint Leads to More Serious Problems!

Hey guys in the video I'm going to show you today, the original call was because of a loud noise when the air conditioner shut off and they happened to mention that it wasn't really keeping up very well. Well the noise problem I quickly diagnosed and I'll show you exactly what it is but the reason it was not keeping up was a difficult thing to diagnose. I'll admit I kind of knew what it was as soon as I saw it but I walked through the steps of eliminating every other problem before I decide what's wrong and what needs to be replaced. Stay tuned I think you'll like it. What the customer is describing is a noise a bang it sounds like somebody's hitting the hammer with hitting the air conditioner with a hammer when it shuts off. I have some real good ideas about what that may be I've come across it several times and I'm going to hope to catch it on camera so y'all can hear it and then hopefully show you what it is. No sir um you can you can leave it on right now um yeah I'll take care of it. Okay what I'm listening for when I push in the contactor is not necessarily a noise when it starts but a noise when it shut shuts off listening specifically to this motor. Okay that's the bang well it's not as loud as I thought it would be so now we're going to kill the power and we're going to check on the motor and check for a couple of things specifically. This is an older system like 15 years old this noise may not explain why their system has not been keeping up but it is something that can normally be fixed. Got all that shaking there's something first I want you to see something y'all see that rust it's coming from between the blade and the hub that's my first sign that the my idea of what might be wrong is correct. To test it is to see if the blade is actually separating from the hub I'm going to grab the shaft that is hard to see actually I think but this is moving the hub this hub right here with the screw in it is firmly attached to the shaft so the blade and the hub should be one piece they're actually kind of stuck together kind of like a rivet but right now if y'all see this it's moving just a little bit so the sound is not coming from the motor but from the blade itself and it will eventually get so bad that this will separate completely and it'll just bend. Okay what I want to explain the noise that we heard when this system is turning when the fan is turning it has a lot of force in one direction and then when it shuts off the weight of the blade and the sudden lack of electromotive force turning the shaft causes the blade to put a force in the other direction and that makes a boom when you hear it it hits with an impact and if you allow it to continue to happen that impact will slowly make it worse and worse and worse so we need to replace the whole blade. I'm going to go ahead and fire this thing back up that blade is not bad enough to keep it from cooling and these customers complain that it's not keeping up which tells me we probably got another problem and like I said this thing's 15 years old and happens to be one of the first ones I ever installed so this is a longtime customer here I will mention that sometimes a motor can make that noise and and it's not the hub or the blade a faulty motor can sometimes make a noise like that the motor not the hub so you always got to check the hub first to eliminate it let's get this thing to come on while I'm waiting on the time delay for the air conditioner to come on I'm going to go ahead and push in the contactor again so y'all can hear this and understand what I'll maybe help understand what I'm talking about that's what I was talking about that's the hub coming loose from the blade at least in this case that's what it was it is not too uncommon to find something like that let's wait on this to come on and we'll check pressures blown blown blown blown all right I think we just I just heard it click so I think the thermostat has just decided it's time to bring on the cooling and this is somebody else down here I think the drain has gotten backed up and flooded the bottom of the system that's why I can see some of this water it's not necessarily from rain I don't know if y'all saw that but that was bubbling when I took the cap off the Schrader valve was bubbling that's not good but if it is low on refrigerant that right there is an easy fix thank you I would not say it's low on refrigerant um but that suction pressure looks really high it's not but uh that makes me want to check temperature drop that suction pressure's kind of high I'm expecting something more like 125 to 130. yeah let me go in and check temp drop I'll be right back yeah that suction pressure is still kind of high in my book that vapor saturation temperature is kind of high I'll say let me get to my temp drop okay y'all see that is the difference between those two outlets where y'all saw me put the um the probes it's going up slowly but I need a temperature drop of something more like 14 or higher in order for this system to keep up ideally you know textbook you're going to want something like 18 but when I'm measuring from the filter to the register something like 18 is kind of really hard to achieve and in my opinion if I'm getting something that high I'm going to start looking for airflow restriction but if you're measuring just across the coil or at the back of the unit from the return to the supply you might be able to get an 18 but that right there is really low there are some things I'm wanting to check in here like superheat and subcooling right now that uh suction line feels very cold I mean really cold and my liquid line is right beneath that spinning fan blade so I have to be real careful if I'm going to let it run and check it okay so I need to connect this on the other side of that txv it doesn't have to be after that liquid line dryer but this ain't gonna be easy tell you what let me take that off there we go that is my liquid line and I gotta tell you this right here is hot you don't ever want to get your fingers caught in that fan blade I have done it I have done it and I had to immediately go get stitched okay my temp drop has increased to 10 that's better but this is something I wanted to look at my sub cooling looks pretty good we have a txv head pressure don't look bad that suction just looks really high and um that superheat is low the low superheat makes me want to look at the evaporator coil so that's my next step it is dirty although this is dirty man look at that look at that wheel it looks worse than it is it's not built up terribly let me get a water hose we are going to wash this out one thing I will notice is that the dog hair that y'all see has a line at the top and that's because this insulation was folded down over the top of the coil so we need to clean the coil and somehow make sure that doesn't happen before I wash off that coil this right here and that little bit this is what was over the top of the coil and honestly glue is not going to work and that's what it looks on the other side looks like on the other side I got some more of these to do I'll show you when I'm done we got some extra screws in it and this is the end result now see if I can get that where to adjust the light let's work on that the drain pan is oh I got I got sludge coming out the drain pan look at that I don't think it has drained in a while I don't know for sure if we have resolved the problem enough to get our temp drop any higher I think it will definitely be I would hope it would definitely be better but we're about to find out y'all don't let me forget that my probes are in there now remember we already had a high suction my super heat should do better but it is not I've got to let this run a while to see where my temp drop goes to it's got to get a lot better than that this is my temp drop I'm still hovering around nine and a half that might improve a little bit these are my pressures and temperatures that pressure is a little bit high and this pressure is really high I would expect a pressure like this if it were over 80 degrees in there okay so maybe we can get back to this I think if I were overcharged this number right here my sub cooling would be high that to me is a normal sub cooling none of this is normal though honestly if I had a good reason for those pressures to be that high this saturation temperature should be higher so now we need to look at TXV reversing valve and even the compressor figure out why we're not getting the pressures and temperatures that we need I have moved my temperature probes this is suction coming out of the evaporator and I have put the other probe on true suction before it goes into the compressor there's only probably about maybe a foot of pipe between the reversing valve and the compressor so what I'm actually measuring is the difference in temperature between suction coming out of the evaporator pull and suction going into the compressor and that is a check on the reversing valve so let's look at it these are my two temperatures this is what's coming out of the evaporator that's what's going into the compressor two degrees that is very acceptable to me I think when you start getting around five or six you might have a problem but just a little bit over two degrees like three degrees maybe that's pretty good so that's good news it does not look like it is the reversing valve so we are zeroing in on why I have such a suction and why my temp drop is only about 10 degrees not the reversing valve and with this sub cooling I don't think it's low on refrigerant next thing I'm going to check is make sure the compressor is pumping and by that the way I'm going to do that is very basic I'm just going to check amp draw on the compressor and I'll share it with you that is 6.26 amps that is kind of low my total amp draw is 8.97 which tells me I do not have a heat strip running but that's 6.26 amps compressor my RLA is 13.5 that's about half of my RLA truth is that's not too abnormal it is a little bit low but not sure at this point if my txv which is one of the last things uh to check if it were restricted what in holy smokes hold on just a second let's do it all right I have killed the breaker that feeds the contactor over here if y'all will look at this this is a device installed by the electric company to cause a time delay when when the power comes on and it is breaking yellow for the time being I have bypassed this electric box its whole purpose is to cause a time delay we have a time delay on the thermostat and on the board so um between you and me I have a lot to do today my phone's ringing off the hook because it's hot so I'm trying not to stress okay so I'm going to try to think this through with you a little while ago I said if the txv were restricted I'd have a high superheat that high suction pressure makes it obvious that the txv is not restricted but the txv can be flooding the evaporator and that would give me a low superheat it would create a higher suction pressure which might also reduce the amp draw on the compressor a little bit if the compressor was not pumping that head pressure would not be that high I know I'm gonna have some critics are gonna say I'm wrong but I'm gonna call this one the txv I think it is stuck open and flooding the evaporator that's just my educated guess I'm not perfect in my diagnosis but this one's kind of complicated and I think that's what the correct answer is so I need to give her an estimate on a txv and a fan blade dryer and four hours of labor it ain't gonna be cheap if y'all differ with my opinion and you can back it up with some of these numbers please feel free to comment because I don't just read them some of the new guys read them too and um it may be helpful to somebody thanks for watching check out the store in that corner if you want to be an ACIQ dealer there's a link in the description and we'll catch you on the next one