HVAC: LG MULTI V Inverter Compressor Failure Investigation (LG CH21 - LG CH26 - LG CH29 Error Code)

HVAC Service Call: HVAC: LG MULTI V Inverter Compressor Failure Investigation (LG CH21 - LG CH26 - LG CH29 Error Code) LG MULTI V Not Heating Or Cooling (LG Error Code CH21) LG HVAC Troubleshooting / LG MULTI V 4 Error Code CH26 Repair (Inverter Compressor Overcurrent) LG MULTI V IV Compressor & Inverter Board Replacement (LG MULTI V 5 Repair) HVAC (Heating, Ventilation, Air Conditioning) Service Call: LG Multi V IV Error Code CH29 (Inverter Compressor Over Current) Error Code 291 / LG MULTI V 5 ERROR CODE CH29 - Outdoor Unit Inverter Compressor Over Current ( Outdoor Unit Inverter Compressor Fault Or Drive Fault) LG Troubleshooting / HVAC VRF VRV Training / LG MULT V Not Cooling (LG Multi V 5 Error Code CH26) VRF Troubleshooting/Repair / HVAC (Heating, Ventilation, Air Conditioning) Service Call: LG MULTI V IV Not Cooling/Heating (LG Multi V 5 Error Code CH26/Error Code 261) LG Error Code CH21 / LG Error Code 211 / LG Error Code CH26 / LG Error Code 261 / LG Error Code CH29 / LG Error Code 291 / LG Error Code 21 / LG Error Code 211 / LG Error Code CH21 / LG HVAC Training / LG HVAC Troubleshooting / LG VRV / LG VRF / LG Heat Recovery Heat Pump / LG Heat Pump / #HVAC #LG #HEATPUMP #JUMPERMANTECH #HVAC #LG #JUMPERMANTECH
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[@richardbartlett6932]

You're doing what i used to do when i didn't have a clue. Just start testing stuff that doesn't matter to stall for time waiting for god to send a message 😂

[@daniellonergan5669]

We've all waited for the ac gods to give us a sign 😂😂

[@eunachooo]

hes checking everything step by step i wouldnt say no a clue

[@MT-9222]

😂

[@jaigobinbhi9804]

Never enough training when it comes to vrf systems.. pain in the ass.. goodjob man...

[@ares3914]

Yes it's the piping in that install. You need to have a oil trap every 15 feet on the riser as it goes down in floors and an inverted trap when it gets to the condenser on the roof. The piping is going straight below the unit not allowing the oil to return sufficiently. Also these units are strict on how far and how many 90's you may have on the system before the unit is undersized. The problem I see here may be both the piping is wrong and not piped to refrigeration standards for oil return and the length of the line sets are just great for the units to handle. The units would do well if piped in correctly and sized accordingly. You may need to add an oil trap at least by the condensers to help the compressors last longer and take pics of all the piping of the units making a map how it's piped and talk with LG and see if they have to long in length linesets. Also see if LG has bigger compressors to so you don't have to repipe the whole building. I have seen this same type of issues on on a new building in San Francisco were the compressors were burning out and all were tied together to serve the building master slave. I found linesets were to long and oil return not sufficient and had burnt oil from the high temp and high Amp compressors. The install was 3 years old and the building had to 3 compressors burnt out. The worst install I've seen. Of course the company was happy for the business but the work was not fun because you have to look at every aspect of the install and look at it with both installer and service eyes. Invite you bosses to the call and ask for help. This is not a easy fix nor a small problem. This can turn to be a big lawsuit on install company or contractor and they may have to return and fix the issues free which they won't. You can bandage the symptoms but you won't fix the problem unless you address the whole system from piping length, oil traps, sizing, insulation, distribution boxes. All has to be looked and measured. Good luck. I surely don't have the patience to deal with that headache.

[@qomco]

Ive seen this in person too. In the install pipe diagrams there often isnt oil traps specified. If its not in the prints, it wont be installed. How does this get passed over?

[@coledevine8188]

You do realize that you don't trap vrf equipment at any riser right? Go ahead and read the lg multi v iv install manual before claiming to have answers.

[@dimaslespier2688]

Typically when we run into that many compressor problems we would measure out the entire liquid line by pipe size from end to end Re calculate the charge We always find its a charge issue

[@ratchetweasal2gaming944]

That’s what it is either that or an obstruction in the line set itself

[@andyreyes6464]

This has been the most detailed video with the manuals and the sample of the serial number of the equipment and the test of each system board, great work, great information, I recommend this video to any technician

[@stevencossaboon3237]

Nice work Jumper Man. It's getting to the point with these systems you need to be a computer and electronics tech.

[@AriefSrimoyo]

Not to

[@Paul-IE-Repairs]

try not to overthink, load current rises due to load or voltage drop, if your voltage to the compressor is in range, then you must have a charge, excessive load issue

[@TooMuchControversy]

Overcharged most likely. Leave the amp meter connected on the compressor supply voltage wire. Remove some charge. When you see it hit your target amperage(17-21)you should b good and safe until a nicer day.

[@christiangv24]

Yesss bro ...

[@JimmyDBlock]

This worked for me temporarily. As I was buttoning the unit up it tripped code 29 again

[@charlespipitone2324]

All this technology is impressive. Give me a block of ice, and a fan, I am happy. Keep up the good work

[@DC-do8vd]

With over 20 years in this trade, I can tell you two things that I have learned when it comes to troubleshooting. One, always start with making sure that the unit was installed properly with the proper piping, refrigerant charge, etc. If it was not installed properly to spec, you’ll be chasing your tail all day long. And two, never put 100% trust in the manual.

[@Joemccrary1]

Did you ever check amps at the input side of inverter board? I wonder if the RLA rating on the cover is @208/60hz and the inverter board is possibly running a lower voltage and higher amps and frequency on the output to compressor where you had your clamp. I don't know too much about the LG VRFs but just wanted to throw that out as a possibility.

[@axelfelix1536]

Great video man! Very instructive for us who are learning about Inverter compressor’s.

[@robertdavenport9095]

I am certain that this system is overcharged. Superheat and Subcool we can’t use on these units. When I have troubleshooted this unit I was told to use Temperature Pressure and Amps to use as a reference the higher the amps is an indication of an overcharge and lower amps are an indication of an undercharge. Great video.

[@JimmyDBlock]

I’m going to go back and let sum charge out until I see a change

[@keithcress1335]

As mxslick50 mentioned earlier, you cannot use a "normal" clamp-on meter to read the current into a motor from a VFD. This was even demonstrated when the two meters were both clamped on at the same time. They didn't agree because they both had no real clue. However, the VFD, in these OEM system cases, have to know precisely what the current is to execute their function. You can usually ask the VFD what the current is. If you can, that is the only current reading you should consider in troubleshooting and it will be VERY accurate. This is why your readings were mind-boggling high. So high, the compressor would have smoked or tripped off long ago. It was all a wild goose chase invented by your multi-meter(s). BTW: Often you can also ask the VFD for the power, which can be very helpful.

[@Rodj12341]

You were reading the testing procedure for the diode bridge wrong, it does say that when you have the red multimeter lead on R/S/T, you need the black lead on the +/P terminal, not the -/N terminal. When you have the black lead on R/S/T, you need the red lead on the -/N terminal.

[@intertwined1813]

Yeah I also noticed that he was misinterpreting the directions

[@mxslick50]

He does a lot wrong with his electrical troubleshooting. Most HVAC guys have no clue how to fix ekectrical faults (just as I would have no clue how to deal with hermetic systems.) In a case such as this, it would greatly benefit him to find an electrician familiar with motors and controls, and work together to diagnose the problem.

[@christopherleubner6633]

Ime when the 3 phase bridge in a VFD blows, it BLOWS, as in either burns up or physically explodes😮

[@georgetabatadze2192]

I experience with LG and what I see on the video the unit OK runs fine and I think so the charge is not the issue there the issue you have there is Installation the piping. You need to check the piping. This is the problem .100% sure because I have the similar problem on the building, so took me some time to figure out. Good luck my friend. If you have any questions you can send me email I working in New York as well

[@zekenzy6486]

Great Video. Thank you for sharing.

[@danlestrange001]

Hey man, assuming all the data on the LGMV is been read at the same time, check out indoor unit no. 5, for 130 pulses on the EEV, there should be flow through that unit, even though it is switched off, so this is most likely causing the high pressure trace to overshoot the target pressure, this will cause in turn the compressor hz to drop, due to a possible restriction. Also "INV Input CT" is only 8.4 amps this is what the info plate running current equates to, so not nearly as high as the rated 14 amps. Good luck.

[@user-mk3np8wi8z]

The piping system is the research that I would do in the location. Good video. I would also use a computer to diagnose the refrigeration system and all the temperatures at the terminal units.

[@user-mk3np8wi8z]

Sorry, I wrote the comment before you showed the app. Good choice.

[@k.y22]

thank alot Jumper man . good job.👍👍👍

[@garenharutyunyan4275]

Great troubleshooting bro Good luck !!!

[@YuriMisi]

Thanks for video, need continue

[@BasketballAve]

Over amps may be due to over charge VRF systems are very sensitive to weight of charge. Usually it’s calculated by the distance of pipe. Also in cold weather it’s very important for the crankcase heater to stay on as to not let the oil migrate out of the compressor. If you shut off main for over night you should turn on main unit but leave off for a few hours to allow the oil to migrate back to the compressor

[@_NCR]

These things always grenade themselves in heating season. They run balls out at super high hertz to get the heating capacity they are rated for. From what I could see in your video the total charge should be 27.85lbs, 16.9 for the ODU + 10.95 trim charge for the IDU's(I got that from the white paint marker on the unit). You can change the measurements from metric Kpa to PSI and F in the app settings. Good luck brother, I see many more days at this place in your future.

[@Rodj12341]

From the Multi V units at the building I am at, the only thing that runs at high hertz nearly all the time when in heating mode is the fan motors(~1000 Hz). The compressor hertz still run at "normal" frequencies similar to cooling(typically 20-50 Hz).

[@_NCR]

@@Rodj12341 Heat recovery systems run all the way up to 150hz in heating by design. Low ambient temps (think under 15 degrees F) and high heating demand make them rip.

[@christopherleubner6633]

Excessive icing on the evaporator in heating mode generally indicates an insufficient charge or extremely dirty air handlers.

[@Pippy626]

Yeah it’s a combination of problems. But it’s NYC no one does preventative maintenance.

[@johnwalker890]

Good job Jumper, But there could be restriction in the piping, or TXV, and the electrical service could be overloaded and causing the compressors to single phase, and the heat pump side of the condenser can pull more amperage under load during the winter, not sure, but the city electric company could be having issues, they could be having problems because of how big New York City is, Just like California, and they probably don't want to tell anyone, it could be more than one thing.

[@tschuuuls486]

Single phasing is not an issue here, the control board handles phase monitoring and controls the frequency of the power going into the compressor.

[@gordonpotts753]

I would recommend u get a remote display amp meter, so u can check amps with the panels on. I realize ur in heat mode but it will b diff with the panels open.

[@JumpermanTech]

Im with you but the truth is, you get the same amperage with the covers off. In most applications, the panel will affect amperage and pressures but somehow not with this. I have the LGMV tool so with the covers off I can read two types of amperage with these units using my laptop or tablet. Strange stuff. Thanks for the advice & for watching!

[@tschuuuls486]

My guess is that it's trying to do the oil recovery cycle first thing when starting up. Therefore running the compressor on absolute maximum rpm to get the most pressure and get the most oil back. Running on high amps for a limited time isn't inherently a problem, because the PCB does know the exact inverter and approximate compressor temp (ambient temp) and will ramp down if it detects overheating (which is unlikely as it's freezing out and the unit fan provides tons of airflow).

[@R290s_biggest_fan]

If you buy a boat you should name it LG multi V

[@psychomokus123]

It could be airflow issue/plugged up air filter down in the indoor units, also i’d love to see system pressures

[@Neto-1984]

I'm with you. Dirty filters/dirty indoor coils would definitely affect a heatpunp in the heating mode. Seeing he has a common problem throughout most units, it probably lack of maintenance by the hotel.

[@Neto-1984]

Dirty filters/dirty indoor coils increase headpressure, which increases compressor amp draw, no matter what the outdoor temperature is. The indoor coils are the condensers in the heating mode. Just thought my comment needed this explanation 😊

[@logankollatt2857]

I was always taught check flow before charge

[@thesilentonevictor]

Man you make this one look easy Great job tech

[@JumpermanTech]

& thank you for watching! These units are very complicated. Much appreciated 🙏

[@-iIIiiiiiIiiiiIIIiiIi-]

I knew when these new inverter systems came to market that there would be some MAJOR growing pains.

[@davida1hiwaaynet]

Not an expert on these machines. However, with other units there is a big difference in compressor loading based on outdoor coil airflow. While running the machine with the covers removed, air bypasses the outdoor coil by entering through the open cover, and going directly through the fan. The air doesn't go through the outdoor coil. This causes the pressure to fall, and reduces the flow through the compressor. To maintain high-side pressure and heating temperature in the building, the compressor has to run faster and faster. This will drive up the current and voltage with an inverter compressor. The continued rising amps with the covers off may be explained by this. As for the Korean engineers visiting and not solving the problem... I work in the offshore / power generation industry. Spent well more than a year in Korea at shipyards. They struggle because engineers are expected by their superiors to work well outside their area of expertise. I don't envy you working on these. Would be likened to a version of hell.

[@user-md8dw3nw2g]

Going through the same stuff. Changed 5 compressors and multiple components in a year. Changed piping arrangement where possible. It’s LG they are trash, way too complicated.

[@richardbartlett6932]

Just to say my mate was LG uk service manager a few tears ago. He would meet with LG technical in Korea. Said they were dreadful. After hours and hours of arguing about the spec said they lied about the kit on a regular basis and it was all about cost cutting he left as he felt they were not trust worthy after few years it'll be all swapped out with some decent kit. Their small stuff is decent their older bigger kit is a challenge lets say.

[@garysmith9772]

I don’t think anything’s wrong with these units. These units are so sophisticated that they measure virtually every possible input and output and control everything. It would not let that compressor over amp if not programmed into the computer. Let it go and best of luck.

[@HVAC544]

You are assuming a lot of things. These units are only as good as the logic programmed into them. I've personally seen these units run in way that will cause damage to the compressors. Installation and commissioning are insanely critical on these units.

[@prowesstv]

For compressor health i would try limiting the output to around 80 to 90% and see how my amps look. Not sure if these LG's have that feature other brands i work on do🤷🏾‍♂️

[@Rodj12341]

I would highly recommend running some of the diagnostic check procedures(Fdd) on these units that are in the service manual, they can reveal issues that you can't find normally. To have the system verify that the refrigerant levels are correct, use function Fd3/Fn3 for Cooling or Fd4/Fn4 for Heating. With the LGMV module connected, run the Integrated Test Run(Fd5/Fn5 for Cooling, Fd6/Fn6 for Heating). It should save the results such as if the EEV's are operating correctly into the LGMV, though it might display it on the display as well. I would also recommend enabling SE5 on all of the units to have them operate the Oil Return operation more frequently. If you want, I can email you more details about them.

[@electroshed]

Does that dongle allow you to graph data over a period of time, or could you leave a small computer attached to the unit to log and/or allow remote access to the log data? I've managed to diagnose issues before using temperature graphs and being able to spot anomality's - LOL definite job security, for the hotel: just buy a load of heaters for the rooms!

[@mikepow48]

Check the amps on a few of the end units that are getting better air flow. could just be an air flow problem due to the close spacing

[@marcoferreira226]

I found when testing vrf units always best to have all the panels on, I use a the Redfish meter so i monitor with the app with the panels on. try to get the software for the lg and a laptop, possibly of a problem with piping and indoor. You need the as-builds

[@JumpermanTech]

I tried testing refrigerant pressures and amperage with the front panel on and it didn't make a difference. Other units, it does affect the head pressure but surprisingly not with these units. That sounds like an awesome meter. I ended up getting the software and connected it to a laptop. That will be my next video release. I did connect a different tool in this video to my phone which essentially does the same thing. Monitors and controls the unit. Definitely need to look into the outdoor EEV and monitor that. Thank you for your input and for watching! 🔧⚡️

[@ericmilburn9841]

Have you checked the amps with the panels on? Is your condenser fan motor amps high also?

[@myshadowkungfu]

Early on he says that because you can see through the coil there's no obstruction. Welllll...in an area with construction or say a concrete plant where fine particles are airborne, a coil can be dirtyly coated but still have visibility through it.

[@buntykainth3699]

When i do motherboard repairs, one thing i always say out loud is, ‘Red probe on ground’ then i test with the black probe. Thats the way to always test.

[@thesilentonevictor]

To determine the root cause of this problem you need to have the in door units clean an start from scratch

[@dewetbritz5715]

... the supply cable looks thin will have an affect on amps .... running at 17 amps ill say depending on supply lenth a 4mm or 6mm supply cable will be good because there is an inverter there is other electrical things to take into account.... be sure your supply is correct...

[@dewetbritz5715]

Cable sizing... cable sizing..... Im So excited that youll fix it by fixing the cable sizing

[@stangaloski4208]

My vote is way overcharged or wrong compressor. Leaning on overcharged. Would be nice to see pressures

[@scottdavis6717]

You aren’t letting air pull through the “condenser” evaporator in this case with the heat pump.. need the cover on for a proper test

[@frankingrassia1272]

I have ran into this issue before in midtown. If they recommended you to Klima they are a waste of time. You need to pull the entire charge out, clean all Evaps, and try to get measurement on the liquid lines. Charge according to their specs. Also confirm that the branch boxes are operating correctly. I give you a lot of respect…. LG VRF are garbage units. Good luck though!

[@XolaresTiberius]

LG has been having issues with their fridges compressors also. Think there is a lawsuit or something in US right now.

[@rogdrickcurry1259]

I heard about that law suit.

[@matthewcarello9280]

The reversing valve has a very tight mesh strainer in it. That may possibly be plugged

[@mxslick50]

You CANNOT read the output current of ANY VFD with a standard ammeter!!! The modulation frequency on the output WILL produce false readings, ALWAYS. You can read the current on the INPUT side of the VFD and add the current drawn by the VFD electronics to get a close approximation of motor current. In this case, if the motor were actually running overcurrent, the VFD would either fault with an overcurrent alarm, or burn up. Again, NEVER use a standard ammeter on a VFD OUTPUT. (Same goes for trying to read output voltage.)

[@_NCR]

You can see in the screen shots of the app he showed that the amps are right at what he was reading with the clamp(INV1 phase ct at 30.8).

[@shifter8207]

What are you referring to by standard amp meter ?

[@mxslick50]

@@shifter8207 The meters commonly used, such as the Fluke in the video. Because of the very complex waveforms in a VFD drive output, it takes specially calibrated and filtered meters to get an accurate reading. Common meters measure assuming a clean 60 or 50hz waveform. (Or DC also in some models.)

[@mxslick50]

@@_NCR Timestamp? In any event, my comment is still correct. refer to any VFD manufacturer's instructions and they will all specifically state that you cannot get accurate (key word, accurate) current readings using standard clamp meters. I have been involved with VFDs since the very beginning on both cinema and commercial motors, and had training from ABB and Danfoss, both of whom pointed this out as the biggest mistake commonly made while troubleshooting VFDs. They also suggested the input side readings as I said above as a solution to that problem.

[@keithcress1335]

Absolutely correct. You cannot use a "normal" clamp-on meter to read the current into a motor from a VFD. This was even demonstrated when the two meters were both clamped on at the same time. They didn't agree because of this. However, the VFD, in these OEM system cases, have to know precisely what the current is to execute their function. You can usually ask the VFD what the current is. If you can, that is the only current reading you should consider in troubleshooting and it will be very accurate. Often you can also ask the VFD for the power, which can be very helpful.

[@andyreyes6464]

probably over charged & dirty evap coils or check the sensor at the indoor unit and out door unit they might be miscalibrated and giving wrong reading to the main pcb. last thing i might think is to provide insolation to all the pipes coz probably the return gas might be getting condensate before arrives to the compressor (wet gas) due the weather and causing the compressor to work harder. please let me kwno what you guys think coz i dont work in vrf but considering the weather conditions that might causin problems with the system also the compressor needs the insulation cover as well

[@bohanger6315]

Why is IDU 5 pipe in (out in heat) temp 6.24C. Just came out of cooling? Would be nice to show a picture of the HRU info tab, specifically the SC in and out temperatures. Not sure the amount of runtime before those screenshots, but it looks overcharged. You have 3121 kPa (450ish PSI) running at 20 hz with no oil in the compressor, receiver in light is on, low main EEV position at 300ish, floodby on the condenser subcooler at only 8 pulses open and elevated amp draw on the compressor. All of that with only one indoor unit calling. Looks to be a standard case of refrigerant overcharge. No oil is going to take this compressor in short order over the winter.

[@Rodj12341]

Is there a good way I could contact you? Our building has a Multi V IV system on one end of the building and a Multi V 5 system on the other end of the building, and there are some odd behavioral issues on both ends that I would like to ask you about and show the cycle monitoring points to see if you might have a solution.

[@bohanger6315]

​@@Rodj12341 To respect your time and money, I do not think I can adequately or confidently offer solutions without being on site or dedicating more time remotely than I am willing to. Far too many variables. I can make snap judgements based on data, but I can't stand behind them fully without the full picture.

[@Rodj12341]

@@bohanger6315 That’s fine. I’ll just describe the two issues to see if they might be a simple fix or something I should look closer at. All are heat recovery models. On the Multi V IV system, when the majority of the IDU’s are heating but there is a unit that is cooling, it puts the ODU into cooling mode. When it is operating like this, all of the units that are heating have a reduction in heating capacity, and the pipe temperatures are only getting to the lower 80’s(Fahrenheit). As soon as there are no units cooling and the ODU switches to heating mode, the IDU’s heat properly again. This isn’t an issue on the Multi V 5 system. The next issue is on the Multi V 5 system. On one of the ODU’s at random days when cooling, it will only run 1 out of the 4 compressors(2 frame) at around 30 Hz even when there is a heavy cooling load. The pipe temperatures of the IDU’s will only get down to the lower 60’s, and the EEVs of them eventually open up fully(1350 steps?), there was even a time where nearly all IDU’s on this system were open fully. After a manual restart of the IDUs operation mode or after a few hours, it will correct itself and either run the one compressor at a higher frequency or run the other compressors where the IDU’s will start cooling properly again.

[@bohanger6315]

The Multi V IV sounds remotely correct. The condenser logic in cooling targets evaporator saturation temperature, and runs the compressor to meet that, while adjusting indoor unit EEVs to maintain compressor superheat. This may result in lower discharge temperature, not adequate for the heating demand (depending on ambient conditions and condensing temperature). They sell low ambient cooling kits with actuated dampers that help here. Multiple chassis systems would normally throw a single condenser 4-way valve into cooling to negate this behavior. I wouldn't expect to see the condenser go into cooling unless the IDUs in heat were thermally satisfied at the thermostat or return air sensors. At that point they would go to minimum EEV position and pipe temperatures would be close to ambient, slightly warmer. I would probably look at reducing the heat dead-band setting to a single degree using installer code 15 option 4 on the IDU thermostats to try to keep heating units thermal on, and the condenser in heat. The MV5 with IDU's at 1350 pulses is no good. Starving for liquid. I would recommend using the ITR function on LGMV, entering the calculated charge from LATS. It should return a charge judgement. There are other possibilities there but I would start with the simple stuff.@@Rodj12341

[@Rodj12341]

@@bohanger6315 Thank you for the tips; MV IV: Here’s an example of why I think something odd is going on, if 3/4 of the IDUs connected to it are currently heating and one of the other units starts thermally cooling, it will put the ODU(3 frame) into cooling, even if that unit has a low capacity compared to the rest. On the MV 5 system, I’ve seen the ODU’s in heat mode with the IDU’s cooling/heating simultaneously, or if it is in cooling mode, the pipe temperatures of the IDU’s in heating is still able to reach into the 100’s. MV 5: The EEV’s only get to 1350 during this behavioral issue, as soon as the compressor runs at a higher frequency or runs multiple compressors, the IDU EEV’s drop down to “normal” values(~200-500). I’ll still run the test run once we can get an LGMV module. Is there any benefit to the USB/Serial LGMV module compared to the WiFi/Mobile LGMV module or can you view all of the diagnostics from either?

[@christopherleubner6633]

Slowly creeping up indicates a flow restriction issue as does the frosty line. Im guessing the lines got damaged or plugged. Also do they have a downstream valve that is stuck? Once it hit 30A i would be shutting it down tbh. 😮

[@yeudinvargas7527]

Hi guys, the system is overcharged. You need to recover 15% to 20% of the charge, and then adjust the charge as needed. You must do this for all the systems that are drawing high amps.

[@eloyarevilcagomez7217]

excelente man

[@BasketballAve]

It’s is normal to freeze in heat mode for heat pumps as the condenser is turned into the evaporator to absorb heat out of the outside air.

[@carloscetz8314]

An LGMV tool can help you see through the system

[@bobchamp3159]

Seems to me like it's a charge issue, also the installation doesn't seem right, how you supposed to be able to clean those coils when the next unit is right up against the other. The principal of ac is to exchange heat how can it effectively do that with the other unit right beside it. My 2 cents. The rest you went through all seems right, nice job.

[@jonathancawood8801]

The door being off while testing amps is going to cause a high reading, possible liquid coming back to the compressor.

[@davidperry4013]

You should demo out those problem child oil traps.

[@rightconditions2010]

would having the cover off cause high amps?

[@apollorobb]

You need to take an electronics course so you understand what forward bias on silicone junctions is if your going to test at component level on Inverter units that use VFD's

[@andreyexplorariurbane]

The capacitor was charge on rectification diods...

[@jaytruthson8302]

Compressor amping high because door is off unit…I believe problem is inside building at air handlers

[@jtops3000]

The rest of world already uses R32 rather than 410a. I’ve had some of these LG compressors running high amps. I ve wondered if they are designed for R32, but they just ship them to America anyway.

[@AndreasAndersson344]

👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍

[@petervasilev7924]

What's the discharge pressure and suction when comp is drawing 30amp? What hz? Either discharge/suction is too high, or comp is running too high rpm

[@plushdragon]

there a clog in the dryer in the system or txv. there been other ac vides that show system glogs look at he temp before and after the dryer it should be the same.

[@Miketime969]

Check valve is allowing floodback on wrong side , locking the pump homeboy

[@christopherwalker8327]

pipe sizing at service valve?

[@HVAC544]

What type of indoor units is this site using primarily? If they are ducted air handlers the airflow has to be set through the remote stat by static pressure. Its not like a cassette/highwall where nothing needs to be done. Proper airflow for the ducted indoors is critical more specifically when running heat mode. These compressors run hard in heat mode in colder climates; if the charge and airflow is not right compressors will die. There's a lot to go over on these units from proper installation practices to commissioning. Technically the rep who sold the job should have verified everything was done right during the job.

[@antoniobaez6282]

I can tell, this is why you guys get paid the BIG BUCKS!

[@tonydoyle9054]

2000 years later😂😂😂

[@JumpermanTech]

It's never too late! 😂

[@phillyfitter4079]

Take some refrigerant out. Might be a restriction.

[@charlespipitone2324]

Wouldn't super heat/ sub cooling apply in any of this equation?

[@3dprintershopstudio]

Do you have any error codes?…..refrigerant charge might be wrong, did you check the superheat and subcool? Compressor discharge superheat?

[@szpindelfly]

You need to clean the all indoor units

[@user-mo1in8ry9u]

אתה צודק

[@limodave247]

Put the door back on no airflow thru outdoor coil

[@nickrodriguez8076]

Couldn’t it be because u have the service panels off which will cause the head pressure to rise which will cause the amp draw for the compressor to be high.

[@NewDestinationEng]

To run the charge calculation on LATS you'll need to draw all the piping and you need the length of each segment between ODU and first Y-branch ten to the next an to the next ... ando to each IDU. After all that the LATS software will tell you the pipe sizing of each segment and the amount of R410A charge needed for the system

[@johnmcfetridge3974]

Absolutely a insulation issue. The building needs to stock change out compressors. China said... China doesn't what a war with us. They can easily destroy us financially. You're awesome!

[@AriefSrimoyo]

Damn This fandal?

[@AriefSrimoyo]

This is fandal? Hahaha

[@craigforster9861]

Are they allowed to be that close together?

[@joshuasmith973]

Yes I have the same system at my hotel property I manage and they are all in groups of two and threes side by side like this.

[@alross18058]

What about compressor rotation?

[@carlosvasquez9462]

some times if you have units panels off amps go up

[@MarkP-ci2vg]

In beginning of video u said u removed x amount of refrigerant and put back what u took out,how do u know that’s the correct charge

[@johnlangley6449]

Yeah non compressible very possible and overcharging I seen it so many times 😢

[@MarkP-ci2vg]

Dose unit have hot gas, Whats your pressures

[@richardbartlett6932]

It's a 3 pipe.do you work on vrf?

[@jefffreeman376]

Seems cold outside, why would they call for cooling? When that cold should the fan be running? Oil in those compressor are not meant to run below 55 degrees, data center's call for cooling mid winter, Different oil in the compressor.Change the pressure switch from the compressor to the compressor fan, keep it from freezing. Find the highest electrical bill in the building, its someones crypto mine! Or a grow op lol!!

[@MacLimitRange]

I would just check what reading the other unit gives.

[@edwinvillaceran]

Maybe the mechanically for the compressor the problem

[@dewetbritz5715]

Ask an electrical engineer about power harmonics and how you can solve it give me a shout out if im on track 🎉🎉🎉🎉

[@user-fp3ni9sv6l]

Indoor coils plugged

[@eunachooo]

its install or overcharged

[@liquidmmentm2899]

These units dont have over amp protection? If you passing tag data you definetly will experience premature failures...

[@ErickHernandez93]

Honestly bro judging from that frost and amperage you’re either overcharged or have a restriction

[@johnlangley6449]

Yeah poor installation hurry up and get it done don’t worry about the mule just load the wagon 😢

[@mmorrison6775]

most likely undersized liquid line

[@richardbartlett6932]

Try to get the report from korea tech. He should have gone right through the system inc pipe runs and trim charge, drops etc. We had a very similar issue with a hotel in uk.the pipe runs were completely wrong causing oil logging in the pipes below and compressors were running dry. We were changing compressors every other week till the budget to swap out the kit was allocated Go right back to basics and trace the pipes, headers, height differences and pipe sizes from outdoor to last indoor draw it all out recalculate charge level dirversity factor and confirm it against spec limits. My guess is the gas charge is correct the trim change doesn't seem excessive but check and double check