THEY SAID THE AC IS NOT WORKING AGAIN

[@nolanferry691]

Bro is out here polishing every turd

[@75sRax]

realest comment out here

[@gregmercil3968]

The majority of our work consists of polishing turds. 🤣

[@keith_5584]

*being paid to polish every turd. Less of a hobby, and more like a commandment.

[@HVACRVIDEOS]

​@@gregmercil3968exactly, lol

[@Pyro4100]

@@nolanferry691 there are people out there that polish turds and actually sell them LOL

[@HfJax]

I like how you go through everything and share tips with us techs out there, and also not just going like some other KZbinrs who just change so many parts that didn’t need to be changed. Thanks so much keep them coming.

[@jasonjohnsonHVAC]

You can see the compressor on the left....the paint is gone on the head of the compressor....she's been cooking that oil a time or two. Looks like those junk accuators are getting slightly restricted. I agree this rtu should be put to bed....permanently

[@dumptrks]

Damn @jasonjohnsonhvac your so harsh

[@markbeiser]

It is the natural state of Carlyle scrolls!🤣

[@throttlebottle5906]

I'd say the right one was replaced/failure/burnout. left likely original. possibly a brownout or phase loss/brownout, banged the fuse. even the wires were all rubbed out, none looked to have shorted. the overheated(blown) fuse could have been poor disconnect contact, either tension loss on the blade or the fuse holders. many had hardened spring steel clips that fail with rust, and age from thermal cycling, once tension is lost game over. that happens often on circuit breakers also, at the end which plugs onto the bus bar, when it breaks and loses tension it start overheating and cooks itself, usually wrecking the breaker case and the panel bus terminal. (aka new panel time)

[@LandonShipp]

You're really good. I am an 18 yr old who has been doing hvacr since his freshmen summer in hs. The cutouts made of the compressors say it all! I'm also trying to get my ham radio operator license. Thank you for sharing this and teaching me so much and being such a great inspiration. THANK YOU!

[@grashoprsmith]

@09:25 "they're all rubbing out on each other...that's a mess"...😅😳

[@jamesnorris1272]

Mister, you are one Hell of a troubleshooter and technician; I hope your customers realize this when you talk to them about repair vs replacement (even in CA). You are going to get another call on this same unit (I'm an old 'motor man' and, yes, change the blower motor if they'll let you and 'stiffen' the base if you can). Very nice work on repairing, rerouting & securing the control & power wiring (somebody else has been there before you). Ah, and SPARE 60Amp Fusetrons; Abondanza, Brother!

[@Thesecret101-te1lm]

Great video as always! It would cost like $1 to $2 for the manufacturer of the lockout boards to add LEDs that indicate incoming call, outgoing call and a lockout situation. Add $1 more and you could have two color LEDs that gradually switch color to indicate if a call came within the last few seconds, or a lockout happened within the last few second. Not sure if it would had helped in your particular case, I didn't get which order the lockouts and the economizer control thingie are hooked up, but still. P.S. an argument for repairing instead of replacing is that some parts are fairly new and those that have survived for 20 years are probably good enough to survive almost until eternity.

[@_iLLuSiv3_]

It's like they get off making people guess!

[@markbeiser]

From a manufacturing and assembly cost perspective, I think having an LED to the board, instead of the wire running out to the terminal block, could actually work out to be cheaper at scale...

[@davidrogers8401]

Nice to see how thorough you are. Way to go

[@HVACRVIDEOS]

Thanks

[@richardbartlett6932]

There were times I really enjoyed this kind of mess and others where I thought "Why me?" Great work, you can only do so much but you did way far more than most.

[@HVACRVIDEOS]

Thanks

[@kg4muc]

Thanks for sticking with doing it the right way!

[@YuShudNoe]

I saw the right fuse discolored right away and knew the disconnect wasn’t making good contact. I win ! Haha . Gotta love HVAC!

[@HVACRVIDEOS]

Lol

[@billhill839]

What did you win?

[@olegatormarssmarss1661]

@@billhill839русский мир

[@ChrisV-]

Love the channel bro. You have one of the best channels and I always learn something from you.

[@raysolovic3629]

Another thing to check is the motor pulley, especially for blown fuses and excess vibration. And yeah that compressor looks like its been overheated for a long time.

[@markbeiser]

I tried R-407C in a mineral oil system once about 5 years ago to see what would happen, with the full consent of the owner. It is still working great! Still the only one I'll do that with though.

[@tirbomax]

always great content on your process to NOT screw the customers...very few true honest people these days!

[@HVACRVIDEOS]

Thanks

[@gdrriley420]

I saw that GE distribution panel and electrical space and I was reminded of work in all the wrong ways.

[@Sperkowitz]

I love how you inspect as to why a fuse blew. Many just replace it. Sure something like a rolling blackout or brownout can cause a surge but if not known it's good to try to find out why. It's not always possible and the should call back if something happens again then you know for sure there's a deeper issue that wasn't found the first time.

[@darthdzl]

You do realize that, as much as we don't want anything bad to happen, lots of people are subconsciously giddy at the prospect of the magic smoke escaping every time you say "1, 2, 3, please don't blow up". 😁 May that phrase never doom you. (knocks on wood)

[@gringoloco543]

I actually did have one blow up in my face. I was replacing a Trane contactor with an aftermarket contactor with all the aux switches. I accidentally attached the 24v signal wire to a 480v terminal. The circuit board made a big bang 💥.... I'm new to this industry, BTW... and wondering if I'm cut out for it.

[@Jason-wc3fh]

Well you identified your problem with why it blew up in your face. Obviously 480v going into 24v is going to make the 24v side very unhappy. You said you're new, so mistakes are going to happen.

[@ThatTransistorGuy]

My favorite parts of your videos are when you take apart the compressors! If you could make a playlist of all the videos where you take apart the compressors, that would be amazinggggggggg

[@HVACRVIDEOS]

I'll see what I can do about that when business slows down a bit

[@ThatTransistorGuy]

@HVACRVIDEOS thanks! I really like this channel! Keep up the amazing work. I learn from every video.

[@robertarnold6672]

That was a tough service call but I learned some really good pointers from this video, definitely things that will make me a far better technician than my coworkers, who do not watch this channel or invest in themselves by taking online classes or going to school. Only problem is that I get hit with all the more difficult calls but you can’t grow from only dealing with the easy stuff. Thanks again Chris for making these videos. My abilities & knowledge have greatly increased since Ive been a subscriber!

[@JantjeVloet]

These are the video's i love, I love working on old shit fixing it and making the customer happy :)

[@HVACRVIDEOS]

Me to, thanks for watching

[@Kevin19700]

Another great and informative vid. Thanks for taking the time to thoroughly explain the situation and all of the possible fix’s. A cost estimate for all the repairs VS. what an entire new ten ton unit would cost would be very interesting to know.

[@ErickHernandez93]

Possibly just a weak compressor chris, megometer would come in handy Also possible bad crankcase heater, those could also easily blow a fuse, seen it a happen before

[@ShukenFlash]

It could well have been a combination of all those things. None of them may have been enough to take it down on their own, but if a couple had it right on the edge already any little thing could have tipped it over. I agree, that thing has given them 20 years, it's time to retire and replace it. 20 years is a good run for an AC.

[@terryh8421]

I like the way you find weird problems as interesting!

[@marcusmcduffie2106]

Hello sir a quick shout out to you for being detailed and straight forward with your process. Thanks to your videos and the BIG PICTURE mindset I installed my 1st belt driven commercial blower motor . Keep doing what you do sir your youtube brother/tradesman from ga appreciate you. God bless you see you on the next one. .

[@brianmcdermott2430]

Great info. And troubleshooting. Thank you Chris.

[@HVACR559]

Got an evaporateor change out on one of these next week. Multiple techs have been in this unit over years. It was way over charged, no one seemed to diagnose the plugged accurator's. Low suction add gas. Customer doesn't want to pay for R22. Looking at R422b. If i remember correctly that's like a 10% loss in efficacy. You mentioned not using replacements on a fixed metering device. Compressor has been changed I'm going to dump the compressor it seems like there's too much oil in it. Dripps out of both ports.

[@richardbrooks3569]

I'm always impressed with your troubleshooting skills.

[@HVACRVIDEOS]

Thanks Bud

[@gordonrockafellow1211]

Those Carrier units have a collector tube that ties all the evaporator coil distributor connections to the coil together.. I have connected the condenser liquid outlet line to the evaporator line with a txv if the unit is cool only or a check valve and a txv if the unit is a heat pump. It is a fairly easy work around to put a txv in parallel with the defective fixed orifice s and bring the subcooling down to normal

[@tonitighe4008]

It’s so kind of you to leave extra fuses for the power switch

[@helmsajr]

Great job Chris has always.

[@HVACRVIDEOS]

Thanks

[@stevenhorne5089]

I've never really been conscience of rub outs. But going forward, I always will. I want to go outside and check all the wires in my machine right now.

[@HVACRVIDEOS]

May not be a bad idea

[@alantorrance6153]

My background is not heat engineering (it is office work, and sundry vehicle repairs), but your programme is quite interesting. Thank you.

[@HVACRVIDEOS]

Your welcome

[@thomasmann3560]

I agree with the jade causing the problem. I see the relays on them doing stupid stuff all the time. I'm in AZ so we only bring in minimal fresh air, so bypassing failing jades is common for us

[@markbeiser]

I've had to bypass 3 of them this year, hardly anyone wants to fix them. 2 of them never worked anyway, because they were side return units with the economizer installed for return through the curb, and I'm not even going to try to fight the battle of finding the bits and pieces needed to convert them that the installer trashed. I just wish people would leave the damn bypass plug with the unit when they install it!

[@thomasmann3560]

@@markbeiser crazy, yeah. I had 1 customer want their jade replaced. We had to get it special ordered thru siglers(carrier) and it took forever. It was so dumb.

[@kens.3729]

This Equipment looks Nothing Short of a Nightmare. Your Strong 💪 Efforts are Appreciated by your Customers and your Viewers. Thanks! 👍🙏

[@HVACRVIDEOS]

Thanks

[@DelticEngine]

Interesting and informative video, Chris. That RTU looks like it's been patched up and modified numerous times making it a pain in the proverbial to determine if something is what it appears to be or the result of a 'creative repair' in the past. Regarding the low voltage side, why not get some 24V AC/DC LED indicator lamps and put clips or backprobes on them? Some of these indicator lamps are prewrired and need only suitable termination of the wires. Careful positioning in the circuit would show exactly what is happening and when as well as where any issues occurring. If a camera was set up you would then be able to easily prove what the problem is and what needs replacing to remedy the situation.

[@pigalex]

This. Cheap automotive/hobby lamps that are rated for 24v DC will also run on 24v AC. Could be a cheap tool to add to the arsenal!

[@DelticEngine]

@@pigalex A very simple and cheap diagnostic tool that doesn't need batteries. It would need to be LED and AC rated up to around maybe 30 volts to account for anomalies. The key objective is minimal loading on the test circuit while being a useful indicator.

[@rdalemd76]

Here in Maryland, It’s not unusual to see Restaurants Milking a RTU that is 35 to 40 years old. The Request will usually be they want the Unit repaired and how much. What usually forces their hand to replace the RTU is Water intrusion, Compressor failures coupled with known Refrigerant leaks. That seals the deal every time. Good Video.

[@peterhodgkins6985]

407C absolutely does NOT work well with mineral oil. Good call, Chris.

[@PhantomDragonX]

Yea that's what MO89 is for. if you know it has og mineral oil, don't use a poe spec refrigerant

[@davidhoward2282]

407C + SuperChange. I used on a 2 ton rtu 6 years ago still working good.

[@leroygreen1877]

When I see those thermal fuses blow its normally resistance issue in the disconnect.

[@JantjeVloet]

Yea but the breaker tripping also sounds more like a random short. I wonder when he talked about the second time he went there for a blown fuse if the breaker was tripped again.

[@russellhltn1396]

@@JantjeVloet Maybe the breaker tripped due to single-phasing?

[@leroygreen1877]

@@JantjeVloet Thermal trips are a pain to diag.

[@2packs4sure]

It's these types of units and situations that made me walk away from commercial air conditioning about 10 years into my career back in 1997.. I was tired of working on garbage that was just one patch after the other on top of the other before I got there.. For the next 20 years it was 98% residential..

[@Rico-oy3dc]

Must be lucky. In my area, all the residential are poor clients and patchwork. Commercial is gravy here in WV upper panhandle

[@2packs4sure]

@@Rico-oy3dc I had a good mix of 90% middle and upper middle class clients with a few shit show customers thrown in,, but very few..

[@markbeiser]

It gets real "fun" when the property manager has a "maintenance" guy that takes care of most things, and only calls you after the guy has really mucked it up. VRF systems "maintained" by in house maintenance staff can be pretty extra spicy to deal with.

[@2packs4sure]

@@markbeiser I can only imagine.. lol I saw some incredible shit but 99% of it was analog old school equipment in my day so there were less unknowns and mysteries but still a rat's nest of incompetence to unravel on a smoking hot Houston roof... I DON'T miss it !!!

[@BEASTWRANGLER]

It's not just restaurants it's every places mechanical /electrical rooms. They can't stand the thought of all that space And not one phase monitor to be seen

[@Thesecret101-te1lm]

The solution is to have the electrical panels in a place where it's impractical to store stuff, like say in a hallway. That might be against code though.

[@BEASTWRANGLER]

@@Thesecret101-te1lm it generally is. Locked restricted access to unauthorized personnel etc space

[@jeffmelcher2908]

@@BEASTWRANGLER I’m with you on the phase monitors missing. My Engineered Air unit has one and it did its job a week ago when we lost a leg during a storm.. Are they uncommon?

[@orcus79orca5]

@@jeffmelcher2908 they are, I look after 14 buildings and none have any phase monitoring that I know of, some newer buildings have surge protectors but no phase monitoring, unless there is a stand by generator.

[@THEBRAINANAYTOR]

I remodel Publix as an electrician, and I can confirm. THEY ALL put racks and bins infront of panels and storage in electrical room even though there’s a big sign that says “NO STORAGE PERMITTED”

[@joselanda8316]

Tech - "Sir im going to have to recommend that you replace the whole system" Customer - Why is that? Tech - "Its got gremlins"

[@jrsmyth9761]

I think you may have said similar, but with Y1 & Y2 both on one terminal and not separate inputs to each CLO there was nothing to activate the CLO to lock out when no amperage was sensed on the CLO. (thinking as I am typing) Freeze alarm may have cleared with the door off by the time you got to the clear alarm section.

[@karellfernandez73]

When I think :" I'm learning". Then I watch this video and I know that I don't know what I know because I didn't know ttyty24V, +480 ; restrictions @ bad bearing +100, degres😂😂. Now seriously. Thank you for all your videos, as a new technician trying to have the opportunity to work in the field, I'm learning from every single one. Thank again.

[@HVACRVIDEOS]

I'm glad these videos help in some small way

[@ninnghhizziddha]

Love your videos Chris.

[@HVACRVIDEOS]

Thanks bud

[@Android_Warrior]

Chris, leave California and come to Texas!!!!!!!!! 💪💪💪💪

[@Android_Warrior]

And if you do I will work for you!!!. Just finished my HVAC School.

[@nightshadelenar]

new viewer to the channel, however not the first time i've seen some ratty AC units (military legit has some of the more foul ones!) Older units like that one generally are a menace to keep running past 18-20 years due to parts and other things not being made anymore. Just be glad it isn't pouring water into the building! had a residential AC unit in a home i use to live in had it's coil drains fail, where something came loose and plugged up a pinhole drain. Flooded the entire lower level one week and the military housing people didn't want to fix it. Long story short, we got a new floor and a new unit with proper installers after some angry phone calls to managers of managers.

[@HVACRVIDEOS]

That sounds horrendous

[@Jason-wc3fh]

There are several videos from other HVAC guys who show in detail how to they free up the accurators on these evaporator headers. I've done it myself with total success. The labor is still going to be high for the work involved, but it can be done without having to completely change out the evaporator. Some even have TXV's kits available and you can ditch the accurators alltogether.

[@joeydinner]

If your blue line voltage wire would have rubbed through with your low voltage, you would have seen an issue with your low voltage. More than likely would have lost a component on the low voltage because with that short, you’re sending 120v or high voltage to your low voltage circuit. Ask me how I know… Thanks for sharing your day to day service calls. I’ve learned a lot here.

[@markbeiser]

Q: How many of the low voltage components would fail if that occurred. A: Yes! Most of us have had that particular brain shart. The rest are lying, or newbies that just have not gotten around to it.

[@HVACRVIDEOS]

Thanks for watching

[@raysolovic3629]

I just seen where your blue wire shorted at. On your video at 24:54 look at the door.

[@russellhltn1396]

Sure looks like something happened!

[@markbeiser]

Certainly looks like something ⚡, but looks too high on the panel, I think the cover over the controls section would be directly behind there.

[@LordMondegrene]

I don't understand a damn thing, but these are oddly fascinating... thanks. Subscribed.

[@paulravitsky2898]

Before I was retired I was on the safety committee and we inspected for 3' clearance around all electrical. Someone would have been written up for failing to keep the area clear. Heaven forbid someone needs to kill power quickly.

[@jamestoy426]

Worked for a home warranty customer was low on Freon we only use 407c I told the customer he said go ahead 2 weeks later he has a bad compressor I

[@ehsnils]

At 4:31 I see that the blown fuse is also discolored, which to me seems like it has been running hot for a long time and not just a quick overload. It could be the fuse itself that was the faulty item. That actually happens!

[@ShukenFlash]

I suppose they could always Ship of Theseus it if replacing it is too much hassle. Just replace every component for new so it's still a "repair."

[@DamagedF0X]

I don't work on hvac, but some of the electrical lessons/examples help me in the electrical forklift world.

[@sirraident]

Quick question regarding oil's and what you stated at the end. Would M099 not be compatible with R22 regarding the oils? If not, then would it be a good idea to flush the lines or blow out the lines with nitrogen or just change the compressor? I just want to know what's best practice, thanks you. I have learned a lot from your channel and I greatly appreciate all that you do!

[@HVACRVIDEOS]

Good question, I'm going to try and discuss this further on Monday nights live stream

[@lildrastly5512]

Love the videos 👍

[@HVACRVIDEOS]

Thanks

[@makinbac0n]

Those disconnect switches are serviceable. Those knives just pull out and you can clean them.

[@krisrosvold5007]

Kapton Tape is really handy for insulating cable sets, especially in the carrier units. Any electrical supply should have it.

[@mikefrom3089]

First thing you said it short cycled the the compressor I knew it was an economizer. I bypassed one two days ago that was randomly cycling the compressor 2-10 times in a a mater of seconds. I had never seen that and the boards don’t lock out because it’s not a safety it’s the control that’s doing it

[@fredlendzian7082]

you got me saying 123 please don't blow up I like it

[@Nba19980]

Great stuff

[@Duracellmumus]

Whend i faced so many trouble in unit like this case, i going to do some mechanical integrity checking. If its low the whole unit is going to down often, because the components has disturbed and no chance to do their jobs well and it always causes non-critical isues that way. But when these isues are comeing and going the components gets stressed by eachother and its going to fall most non predictable ways. This is can not be slow down effectivly without get an aceptable mechanical isolation inbetween the problem-sources, to get find them in the usual easy-to-understand work OR not work states. When is achived they going to act as an old component, and start to do their jobs realy well. In this case is lot of effort but take mutch less time compared to fight the seemly “not critical issues”.

[@vandalhero]

i had a stroke reading this.

[@colormaker5070]

i see you have one of my favorite Simpson multimeter in your office. This was my goto meter before we went digital.

[@andrewgilbreath1331]

Bro I don't like 407c personally for 22 replacement, I've had really good luck with 422b and MO99 both work with mineral oil, no oil change is much easier to deal with.

[@rickygammon3522]

Hey bud I absolutely appreciate your videos I’m also a hvac/r technician for over 25 years. Just wanted to ask what kind of issues are you having when you use the 407c in the old carrier units. Just curious I have a few customers that still have those turd units lol. Anyway I know you’re busy but if you get a chance I am just curious. Thanks for all your videos and I’m gonna get one of your hats

[@HVACRVIDEOS]

Hey Bud, good question- I'll discuss this a bit further in my next live stream Monday afternoon

[@Bigman0_0]

God I love the way you troubleshoot. Out of context question, what is that app you use called?

[@markae0]

Nine minute in if you can't wait. Great Video!!!!

[@ritchieortiz5610]

I’ve had an issue with the same kind of unit it was a 2003 or 2004. They had the unit jumped out on running both stages. I ended up cycling the 2nd stage. It was just running for too much for too long. To the amperage would like slowly but surely. I’m here in the Coachella valley so you know the weather I deal with.

[@HVACRVIDEOS]

Yeah it’s hot out there I only have one customer out that way so I’m hardly ever there anymore

[@AllTheOne219]

im early to the non member release

[@blackfirehd884]

9:22 im sorry im too immature 😂

[@HfJax]

Can you do a video about the economizers and how to troubleshoot them

[@ernestrollins383]

10:00 I think something is bent causing excessive vibration and that is rubbing the wires

[@BeastCY2]

Very good Teacher. Dont know anything as Im from the IT field but after years of watching you im trying to follow and understand. Thanks for the great videos

[@HVACRVIDEOS]

Thanks for watching

[@elcrazy8017]

That restaurant needs a PM contract on those units. They are not taken care of

[@HVACRVIDEOS]

So very true

[@sphinxios]

heat up the caps and se if those change value, on the bad ones values will change quite a bit

[@trevorphillips7233]

Gas stations look like that too

[@jrsmyth9761]

I am having thoughts of the Jade located in the blower section is an issue. I have seen a similar issue on a handful of them that are in the blower area and none that I can think of in the controls section.

[@markbeiser]

I think it is less of a problem of it being in the blower section, and more a problem of it existing at all! All 3 I've found doing strange things this year were in the controls compartment.

[@LewisSmith-he6gu]

hello from Poole in Dorset

[@dumptrks]

Another great video bro..keep slamming them out

[@HVACRVIDEOS]

Thanks

[@Roctrin]

22:30 mechanical electrical joints like wire nuts arent designed for the kind of vibration seen here. Lots of poor design in wire routing and termination shown in this unit. Really cool stuff, thanks for your content.

[@HVACRVIDEOS]

I agree

[@crazyedo9979]

An investigation with a thermal camera would be nice to see if there are any resistance related electrical problems.😁

[@davidcraven277]

Is their a reason for not putting the spare fuses in a zip lock bag it would keep them from the dirt and no reason for clean up?

[@Thesecret101-te1lm]

How about dust proofing the disconnect (and the other electrical compartments)? You could for example slightly pressurize those compartments with air from the indoor blower.

[@markbeiser]

While I've never worked out in a sandy desert area, I do have a cement bagging plant I do service for. Nothing, and I mean NOTHING that isn't solid state and/or hermetically sealed is dust proof! Also, if it is an electrical enclosure located outside, and is sealed up almost but not quite perfectly air tight, there will be condensation inside the enclosure.

[@mikemorassi210]

Where would you find SEER ratings if you didn't know what the seer rating was?

[@gregmercil3968]

I had a similar issue today, blank Tstat caused by a tripped breaker. No popped fuses though. I went through the entire system and all I found were a couple of low voltage shorts via wire rub-outs; one was from the defrost termination switch and another was a pressure switch. Not sure how that caused the breaker to trip and not pop the fuse on the board, until I saw that the transformer was tapped wrong. Was tapped for 230 instead of 208. I corrected that issue too, then wondered if maybe that caused the contactor to chatter which could trip the breaker. But the contactor wasn’t burnt up or pitted. One of those weird things that kinda stumped me, but whatever the unit is working fine now. 😆

[@HVACRVIDEOS]

That is Interesting

[@RickRick-sw7mb]

Why did you turn off the disconnect because of the compesser lock out board could of trip.

[@ivoryjohnson4662]

Do you ever put wire looms to protect wires

[@_iLLuSiv3_]

I needed some 409A, now I am converting seals and oil over instead... wow.

[@jasonbecker7143]

If you would give a rating of quality of manufacturers (High to low) what would it be?

[@sparkytech8787]

the blue wire ruby duby looked clean thou

[@Schafferr]

Have you ever gone in with a TXV instead of orfice on those carrier units when they’re plugged up?

[@HVACRVIDEOS]

Good question, I'm going to discuss this on Monday nights live stream

[@HappilyHomicidalHooligan]

If the 2nd fuse to blow was the same one that blew before and was the disconnect knife that's making a poor connection, then the fuse likely blew because the bad knife connection is causing it to heat up and if it gets too hot, the fuse will blow thinking it's passing too much current... Fuses are micro-heaters at heart, the more current they pass, the hotter the fusable link inside them gets and when they get too hot (because they're passing too much current), they melt and a spring pulls the two halves apart breaking the circuit, too much heat in a nearby component (such as the knife blade half an inch above the fuse) will also cause the link to melt, blowing the fuse... When the fuse blew, cutting only 1 of the 3 Phases, it likely caused enough of an Imbalance in the Main Breaker to cause it to trip... In addition to that, I suspect you also have a failing (or outright failed) Jade Module and/or Compressor Lock-Out Board... That's my Theory, though I admit, 3-Phase Equipment, Breakers and Fuses are not my Specialty as an Electrician, my Training and Experience has always been in Residential Wiring...

[@makeitcold6649]

Very nice running that problem down. I had a couple newer Daikin RTUs in June with similar set of issues, I thought it was the Jade controller too. Ended up being a bad factory 9-pin connector to the Jade controller, even having the bypass plug in would occasionally chatter the contactor and trip the breaker. Intermittent electrical issues are the most difficult and fun brain teasers of this trade, imo. I probably condemned myself to another one next week having said that. What are you using to measure the airflow in MeasureQuick?

[@HVACRVIDEOS]

Good catch

[@Pyro4100]

If the compressors are three-phase and one fuse blows they would start to single phase and at some point will trip the breaker because of the single phasing had the same issue with air compressors that are three-phase one fuse blows and then eventually it trips the breaker

[@bashaaksema94]

I will never understand why they use blank wires in america. Here we would definitly use cables and also have to secure them way better.

[@HappilyHomicidalHooligan]

Thank you for going back to this Video Intro. Please don't use the music again, it was excessively loud and even more annoying than it was loud.

[@michelbrown1060]

Do you have a Megger to check the fan motor's windings ? ?