It wasn't blowing fuses, it blew the fuses, big difference. It would be helpful if you stated how many fuses were blown & how many times, b/c you didn't, I'll presume once. I really like your videos, but there are so many problems with this video, I'm dumbfounded, you were not isolated, in the middle of nowhere, this isn't a critical cooling application? And why use a fused disconnect? it's more expensive, & yes, I understand why it was in the first place(I'm not sure if you do?). The gush from the newbies & mediocre mechanics in the replies is to be expected. This reply isn't for you, you should know better, it's for others to think. Again, I appreciate your content & as always your honesty.👍 *Knockout bushing & chase nipples to keep on hand, & ALWAYS in the service truck/van would be Thomas & Betts, aka T&B, two different series, 3210, 3211 & 1942, 1943, both 1/2 & 3/4" respectively, add a number to go to one inch. One is nylon(knockout), the other is metallic(chase).

@HVACRVIDEOS

Жыл бұрын

I'm kinda slow so please explain you're comments better so I can understand them, your all over the place and your assuming I understand your brains way of trying to criticize someone???

@ronh8047

Жыл бұрын

@@HVACRVIDEOS First, thanks for the pinned reply, it's cute. And considering you did, I now feel slightly obliged to respond. Don't play coy or be disingenuous with misinterpreting what I've mentioned, b/c if you don't comprehend what I noted, I've given you too much credit. I took it easy on you in regards to this video, I could have said, if you worked for me, you would have been reprimanded, because that would have been, at minimum, the case & listed why, but I didn't. I concluded this to be for 'content' purposes only. In most of your videos, you state you welcome criticism, you clearly do not.

@pavelkolp

Жыл бұрын

You might be very smart in your own head but make very little sense to everyone else. Stop trying to be a smart ass know it all and just get your point across straight.

@themonkeyspaw7359

Жыл бұрын

@@HVACRVIDEOS I think Ron is drunk, schitzo, or just an idiot. What do you think?

@Hawkers02

Жыл бұрын

@@ronh8047 I'm sorry but even my brain is fried at this comment

It's funny that a lot of technicians at the company I work for watch this page. Always something new to learn, a new way of doing something. Great videos!

@HVACRVIDEOS

Жыл бұрын

Awesome Greg thanks for the nice words!

The why behind what you do is the reason why we love this page 👏🏽👏🏽

I love my thermal imaging camera....lets you see all the hidden effects of electrical and overheating. I use mine for a plethora of things, electrical, in floor radiant, air leaks, condenser coils, valves, air locked hydronic systems, faulty 3 way valves....etc etc. Thanks to someone really cool and generous.....i can now say im a part of the Fluke 1587 club.....its a great tool with megger and conventional multimeter functions. It works with VFD'S, has low impedance...etc etc.....another great video and very detailed diagnostic. You are a great example to newer and older techs on proper practice in evaluating a system and being able to provide an accurate diagnosis That condenser fan motor is running into service factor amps....which isn't a design condition....its a it'll run....but not for long before taking a dump....SFA are a caution that an issue is at hand

Chase Nipple is the correct name. They make them with longer threads (1"). Usually just called a "Long Chase Nipple" or longer thread version. Loved the video, actually was good that you didn't edit the older footage yet so we could see it all at once. Thank you!

Our company primarily works on commercial HVAC/r equipment from 1980-s to 2015's, when ever we come upon a bad condenser fan motor, and the system has 2, and both looks same age or OEM, I always replace both to save myself and the customer a call back, and thats exactly how I explain it to the customer. Great video as always!

Could be with Y1 and Y2 jumped if both circuits come on at the same instance the inrush must have blown a fuse.

8:07 were both of those compressors banging on together since Y1 and Y2 were jumped together? That's a considerable amount of inrush to consider, no?

My guess for the blown fuses would be that the disconnect in conjunction with both compressors coming on at the same time may cause the fuses to blow. Lock rotor AMPs would be very high at startup because of the simultaneous compressor start. The issue with the thermostat should be corrected.

@truckerallikatuk

Жыл бұрын

Yeah, 2 compressors, 2 fans and the blower all coming on at once would be a huge inductive load coming on all at once. Separating the two compressors to separate call circuits would be a wise move. Quick edit: There may be corrosion or bad contacts on the fuse holders, they've been cooked probably for years, and that could reduce their gripping ability. And any reduction in contact would add resistance, which makes heat.

@gregmercil3968

Жыл бұрын

I’m not a commercial guy (yet), but from the few two stage systems I’ve come across, they typically don’t start at the same time. There’s usually a brief delay between stage startups to prevent this issue. It can only take the LRA of one compressor to pop a fuse when there’s a loose connection. EDIT: I forgot that Y1 and Y2 were jumped together on this unit. Yeah this would definitely cause a fuse to pop. 🤣

@tonymorrison9313

Жыл бұрын

@@truckerallikatuk Good point. I forgot about the fans. I work mostly on commercial systems. I see this a lot.

@tonymorrison9313

Жыл бұрын

@@gregmercil3968 I work mostly on commercial units. I see this a lot. It’s usually on older systems.

@jonnymac31

Жыл бұрын

I'd be interested to see the data sheet on the fuses he took out. Even with all loads starting simultaneously it should be nowhere near what the inrush of the fuses are rated at.

You can use your thermal to look at the motor in question and if it’s 180 degree or higher thermal tripping is imminent

@HVACRVIDEOS

Жыл бұрын

Great point!

Glad to see you using a torque screwdriver. Thanks for the video!

You inspired me to start my own hvac channel documenting my daily encounters. Love your content. I’ve binge watched most of your videos. I mostly work on split systems , chillers, boilers and package units , comfort cooling and heating in general, and I’ve learned alot about walk in freezer and cooler and ice machine order of operations thanks to your videos. They have made me much more comfortable when I get refrigeration calls. Thanks for the great content.

Great video Chris!! What a pain with these older units keep the videos coming

As a business owner I've been trying to learn what work I can do on my units myself by watching your videos. Would you please make a video showing what PM business owners should do themselves?

@htroberts

Жыл бұрын

mostly just keep it clean (with water) and change the filters when they get dirty. but if your business doesn’t suck, you’re probably better off finding someone reliable and buying a maintenance contract where they check & clean a coup,e times a year.

@TuckerPatterson

Жыл бұрын

I have almost 20 units. If I can save some money by doing some of the work myself I'm going to do that every day. Covid and inflation has been hard on small businesses so we are trying to save money any way we can so we don't have to raise prices.

@zacharyattack452

Жыл бұрын

A pm would be everthing hes doing now. Checking amps and voltage

@chris76-01

Жыл бұрын

@Tucker Patterson I would say just raise prices but then that will have a detrimental effect on your sales. Inflation is a no win situation when your business depends on customers willingness/ability to spend more money.

@legionofanon

Жыл бұрын

@@TuckerPatterson you could probably google your units to see if theres any specific scheduled maintenance required, but from what ive seen on this channel making sure the air filters are good and not plugged up, and keeping large debris out of the coils will go a long way in preventing issues. And visual inspections will never hurt, and done regularly you can spot something changing and may catch a problem before it becomes a huge issue, like wires at terminals turning burnt in color. Just be careful where you put your hands, dont wanna accidently hurt yourself

I swear I learned something new every video that I watched from you and I've been in the industry for 18 years

Might want to put a time delay between y1 and you, so you don't have both compressors hitting the line simultaneously. Another thing some times techs forget to match the RPM of the condenser fan motor with the OEM, that will cause the CLO to trip.

@AuroraProductions95

Жыл бұрын

If RPM is off on a thermally protected CFM, it will just open on thermal protection. I have first hand experience with this lol 😅

@hvacmisadventures

Жыл бұрын

@@AuroraProductions95 I think he was saying that it would throw off head pressure and it could lock the compressors out on high pressure lock out

Hello brother I just want you to know that I’ve been in the trade for a few years now and feel very blessed and thankful for the good people like yourself that come my way. I have learned so much from your videos and have even purchased tools I’ve seen you use that I didn’t have in the past haha. I appreciate everything you do and the transparency that you make your videos with. I appreciate the mistakes that you make to allow us to learn from them, you have my respect and admiration, keep rolling those videos and ignore the haters or critics, they got nothing better to do then to judge and criticize, your doing the opposite by educating techs like myself out here. Stay strong brother, cheers from Denver Colorado.

I don't know how I found this channel but, I'm fassinated and have seen like 3 videos in a row. 😂

I'm in complete awe of this. I recently stumbled upon something with a similar message, and it was captivating. "The Art of Meaningful Relationships in the 21st Century" by Leo Flint

Great Sunday morning video to enjoy my coffee to. Nice job with the disconnect evaluation. I've seen that happen before where a bad connection within the disconnect causes the fuses to overheat, eventually blowing them open under load. As far as the chase nipple, there are slightly longer ones available depending on manufacturer and what the supply house stocks. Worst case scenario, you could use a ridgid close nipple with locknuts and bushings granted you have enough space between disconnect and unit. Its a bit more pain in the a-- but will allow you to use plastic bushings.

Awesome video and observations as always. Thanks Chris.

Cómo siempre... Exelente trabajo💪👍

Loving the videos mate keep it up. Love from the hvac tech’s from Australia

Very nice vid! Always good content.

Just an idea for the disconnect, at one time I couldn’t come up for a name of a chase nipple and when I was at the electrical supply house they gave me a closed nipple witch is a little longer and of course the plastic bushing for each end I don’t know if that’s an acceptable solution I heard at the end you didn’t want to just use pipe technically this would but it’s not a piece of EMT.

Those Klein multi drivers are very handy. My 1/4 and 5/16 fell off one day but I primarily use it on condenser fans and blower motors. Very handy on roofs. Really enjoyed the video.

Great video! I’ve never seen anyone do an insulation test on anything. I’ve always ohm tested motors and made sure the amp draws were good while starting up and running. Definitely going to look into insulation testing motors.

Always leave fuse for the next guy.I am glad we think alike 💪🏽.

I worked on this same exact model a couple days ago, even had the same square hole where it looked like something was missing. The complaint was that it was leaking water down the vents. Turned out to be a plugged condensate line, easy fix. 😀

Could you have a voltage drop from both compressors trying to fire off at once and causing a short cycle condition and tripping the internal overload?

Higher resistance in the disconnect and fuse holder will not result in higher amps directly, but it will reduce voltage going to the compressors, which makes them overamp, which can cause the fuse to blow. But the extra resistance in the fuse and disconnect will also cause the fuse to heat higher than ambient, making them less resistant to tripping. If the extra resistance was in the contactor, it might not have been enough to blow the fuses. I won't say that closing the air damper helped or hindered, as the makeup air is just going to blow more hot air into the building that the AC still has to cool. A swamp cooler on the makeup air fan might help with that. Just some random thoughts from someone who took a few Electrical Engineering classes

Great Video! Observation: when you manually activated the compressor contactors they appeared on the video to a little 'lazy' pulling in. At the beginning of the video you were getting only 23.5 vac from the transformer and it was connected properly. I did see the 25.7 on your return but the if the transformer was only at 23.5 when multiple contactors are activated it may have kept them from fully engaging. Just a thought. BTW correcting the staging of the compressors would also help as you mention in the recap. Thanks again.

Good catch on that bad disconnect. A question I had: after replacing the disconnect, do you find it good practice to take "after" temperature scans on the new box/wiring to see whether there may be additional causes for high temperature on that one leg (compromised wiring or bad connection/breaker at the panel)?

Good video 👍 work.

For some reason this unit looked familiar with the jumped Y1 and Y2 thermostat wires.

I had the magnet chip inside when using it in an impact drill on the 5/16 x 1/4 nut driver. There good for taking unit doors off not so good for ding install type work

I like to carry a small amount of 3/4 inch liquid tight,this larger diameter allows for those reducing leads to go inside.

The #1 thing I've learned from you is... 11/32 is the socket size I need for those condenser fan nuts. I'm tired of using my wrench

Had a similar problem on a similar carrier. Turned out it had too much refrigerant. Was a single stage .

Nice Dr hvac

You ever thought about 3D printed parts when you can’t find what you want? You could have a new avenue for revenue by building your “chase nipples” to the specs that you need. The printers are reasonably priced and easy to learn these days. I’ve built many plastic parts I needed for the field I’m in and I had no experience doing it.

@tbelding

Жыл бұрын

A lot depends on the environment. PLA, for example, is horrible in humid environments. Many of these systems are in the desert, so who knows what temperature the metal may reach.

I thought on those carrier clo boards that there was a connect on the board between terminals 2 and 3 off memory I thought that locked out each compressor in the event of high or low pressure fault. To me when you pushed in the cofactors and they stuck it would have been worth investigating if there was voltage to the compressor contractor coils if they stuck in like that seems like a low voltage or bad contractor coil issue

@FrenchBeefCDN

Жыл бұрын

Im not super familiar with how carrier clo's work... but if It contains a higher impedance relay that lowers the low voltage to the contactor coils during a fault, by pushing in the contactor manually, it may have enough voltage to HOLD the coil IN, but not enough to PULL the coil in. Just a thought, I will definitely check it out next time I open a Carrier on Lockout. Definitely should have measured the voltages at the coil before pushing it. Ive seen older units have JUST ENOUGH corrosion on the wire connectors to take 1-3 volts out and eventually you lose pull-in voltage at the contactor. Clean the connections and it works beautifull.y

Also, we all know you keep the clear packaging film on the insulation tester display just to mess with us.

Having Y1 & Y2 jumpered can totally explain why the original fuses were blowing - both compressors starting at the same time is a huge inrush current and the circuit was never sized for concurrent startup on those motors

16:14 - Only change / add I might do, poly-bag the fuses, reduce contact tarnish, etc.,

i thought i had plugged orifice recently from plugged condenser, but the factory undersized drier just needed change

I have checked temperatures with a IR gun on top of condenser fans. You can see a clear difference of certain motors rising in temperature. And giving you those intermittent issues. It doesn’t set diagnosis in stone but helps with your troubleshooting.

When contactors pull in after being slightly touched like that... does that not indicate weak or low control voltage/coils?

Chris, where I work, we use stainless steel fused disconnects. The standard disconnects are $200, so the fused ones are even more. The location is a good manufacturing facility, so they have high standards there.

Could I recommend a delay on make relay for one of the compressors.

18:21 that belt is shredding away slowly. Bad T&B should have called for a smaller motor sheave rather than opening it so far it's probably rubbing with the threads. i know its not relevant to the issues but just an observation

as a retired hvac tech 20 + years I like watching your videos on your diagnostics of your rooftop units and refrigeration systems I wish I would have had all of these info back when I was an apprentice we learned from older techs and trial and error. I worked in the upper Midwest area of the country thank you for your videos.p.s we call package units rooftop units here in Minnesota

For the Chace nipple Bridgeport makes long chase nipples. I think T&B has them as well. Just a few thoughts, what was the transformer voltage ? With both y1 and 2 comming on at the same time could the voltage drop causing the contractors to chatter or drop. Another possibility with both compressors comming on at the same time and say dropping out and restarting the starting current of both blowing a fuse?

Have you ever used a hammer to flatten the offsets? I did a job where they install a round unit and had me us a hammer to round the back of the box so it looked clean. It was just a junction box so no poles or coil to damage.

Both compressors turning on at the exact same time might be too much inrush for the fuses. Usually you want them staged. So probably good to change that back to how it should be.

equipment is wore out... cannot get replacement... so..you have to keep patching the turds on the chase nipple... here is a thought.. what about some split loom tubing? any protection is better than none...

I have used stainless nipples with locking rings and plastic bushing to get the length I need for going from the unit to the disconnect.

Always leave extra fuses? Only if the customer approves of the extra $100+ on the bill. Fuses are ridiculously costly nowadays.

Do you have any videos with the carrier package units that have the slanted condenser fan motors?

Our inspectors always make us clamp the sealtite no more than 12in below the disconnects. Plus its in the NEC.

When do you see better availability so you can obtain units easier?

A good replacement for the bush fitting is a cable gland. You need a cable gland for cable protection against chafing of the frame. Strain relief for the cable also comes in handy here.

@BariumCobaltNitrog3n

Жыл бұрын

Oof, you might be right, but the word gland makes my skin crawl.

5:40 the service disconnect has a bad blade from looks of thermal

I'm guessing that Y1 and Y2 hitting together .... so super inrush current ... in combination with the bad disconnect blew the fuses. Also ... I wouldn't be surprised if you get a call back cuz those contactors obviously had SOME voltage and you helped by pushing them in... or maybe it WAS the lockout. Who knows, lol.

what about the 24volt transformer could it be getting weak from the years of use and heat and that could make the fan over amp if there running far to long like all night heat soaking the windings or overheating the bearings because it's not used to running that long

Curious why you needed a new propeller for the aftermarket condenser motor. Didn't hear you say the hub or blades were cracked.

In Measurequick with multiple compressors running different refrigerants are the circuits assigned the refrigerant in setup or do you have to change refrigerant type each time cycling between circuits? Do you use Qbits on your regular customers units to be able to keep records of past readings? $5/yr/unit?

@HVACRVIDEOS

Жыл бұрын

Yes the refrigerants are assigned to the circuits and no I don't use q bits to run reports for my customers they don't want them

Is that evaporative pad like a humidifier pad?

Where did you put your probes?

A comment from your loyal viewer from Denmark I am in IT but I really like your videos. I was wondering if you have thought about going through some AC theory on a blackboard I would like to know the basics of how an AC works and I couldn't think of anybody better than you. :) Just a thought from a network tech. :)

@tuttocrafting

Жыл бұрын

I'm in IT too, and i would love a quick video about all the terms he uses and what they mean!

since the first call you never checked the fan motors bearings manually,the access panel is missing the center piece by passing the condenser,1.40 amps is saying the angle on the fan blade is too high causing premature wear.you need a time delay on make on one of the compressors.very nice video thanks for sharing your work it helps greatly.

what sort of dimensions would you need? looks like a part that could be 3d printed fairly easily @13:33

Hi..have you ever worked on trane chillers

I love my Fluke. lol That delay would drive me nuts..

Are you still using the economizer? Could there be an issue with the wiring/sequencing in there? If you are doing PMs, who else would have made that Y1/Y2 change? If it is just a chase nipple, and not being used to secure the items together, can you just use the plastic washer instead of the metal and plastic together?

I can't find that multi bit socket driver on tru tech tools

Possible that you have a plugged condenser coil? Those carriers are known to have plugged coils that you have to split the coils and clean. On cooler days they seem to run ok and might have a little low charge. But on the super hot days they like to crash on high head pressure even with a slightly low charge.

What thermal device are you using?

Great vid ....On the subject of unit quality . What residential unit would you pick to install in your home ? I'm looking at replacement and i don't want complicated which equals expensive . I don't want any unit that uses micro channel coils or Vfd drives . Any input is appreciated

@Chris_In_Texas

Жыл бұрын

Most residential units don't have VFD's. VFD's are used in three phase motors, not single phase motors. To use variable speed on single phase they use ECM motors. The higher the efficiency the unit typically the more complex the unit. A single stage AC and 80% furnace that would be the simplest. Remember that there are only a handful of actual manufactures of the equipment. Each one has many band names out in the field. Really it all comes down to a dealer you can trust! 👍 Each dealer will have associations to specific vendors that they like to install, could be because they have had good luck and fewer return calls or they make more profit in those brands. Trust in the dealer and pricing can be much more than brand X vs brand Y. Look at equipment warranties and how long labor is covered vs just the parts. Most equipment made today is designed to fail, and if they built it correctly, it will make it through the warranty period before it fails! 🤦‍♂ I see all the time, people say Brand X is the best thing ever, and then you turn around and others say Brand X is the worst ever and they would never use it.

@themonkeyspaw7359

Жыл бұрын

Micro channels aren't as bad as people say. They are easy to clean and i've found they leak about the same as a tube and fin coils.

Also i would amp the condenser fans with all the panels on. The first time i think you had the panels off.

What happens if hydraulic oil finds its way into a r407c refrigeration system? Had a case where a heat exchanger in a oil bath had a leak and sucked hydraulic oil which filled the whole compressor and evaporator. Does the oil have some negative reactions with the system if I dont manage to clean it properly and is it even worth trying?

A rare question for you: how many units have you replaced piecemeal?

@BlueNEXUSGaming

Жыл бұрын

To clarify: I am referencing full unit replacements performed over time, optional if you want to differentiate oil changes, though I was referencing specifically mechanical replacement; Grandfather's Handaxe conundrum, at what point is the original AC Unit no longer the original AC Unit when replacing each part from the unit.

You're going to see a higher current on the fan motors with the service panel off.

if you haven't already found any long conduit nipples(useable as chase bushings), just search for "extra long or long conduit nipples", they generally have 1" of thread length past the hex end. 😁

Does that unit have a float in the drain pain ? If you decide to leave the control voltage wired the way it is I’d put a time delay on the second stage.

First time we've heard contactors look great

The reason insulation tests have to be done over time is because an insulating barrier that large in area forms a capacitor to ground. A capacitor charging seems like a short at first but as it gets charged, less current flows. Resistance is voltage divided by current. Voltage on the cap rises, current drops => Instantaneous resistance goes up. Give it infinite time and it will approach its final value. 'Good enough' is obviously the goal here.

At my one work we used to do a leakage test at if I remember correctly was over 1kv

How typical is it to have a different refrigerant in each circuit?

I remember when I was young lad. I got shocked my hand cranked megger.

im very surprised how mangled those coolong fins are

Have you ever worked with r744? (It's literally compressed CO2) because I'm just curious and where I live (Europe) it's the standard for these kinds of installations.

When you get on old stuff baking in the sun year after year running 24/7 you can only do what you can do

I've actually had the compressor lockout board lock out on me from compressor start up, high load and potentially bad cfm would cause that board to lockout

Can someone explain how the compressors started when the contactors were manually pushed in. How did that reset the lockout? Thanks in advance

@Tsnor150

Жыл бұрын

I was wondering the same thing. Thought that was key, but we did not follow that lead. Someone else said "...When contactors pull in after being slightly touched like that... does that not indicate weak or low control voltage/coils?.."

Anti-short bushings?

50 inch pounds is nearly 6NM, that's INSANELY tight :O

10:42 is trying to ignore that you're looking at a reflection between Chris's legs for a minute.

I got a question (not abut this video though) I got at my facility a System with R404A the head and discharge line of the compressor are at 217,4 °F (103°C) should I call a technician?

@jasonjohnsonHVAC

Жыл бұрын

Is that reading at least 6" from the compressor?

@H4zuZazu

Жыл бұрын

@@jasonjohnsonHVAC I looked at it with a thermal camera (CAT S60)

Those oem motors for carrier are so expensive I put after market all day.

@HVACRVIDEOS

Жыл бұрын

I will discuss this on my livestream on KZread this evening 4/24/23 @ 5:PM (pacific) come on over and check it out kzread.infog7_emG3FE1E