Is Your A/C Unit About To Die? This Tool Doesn't Lie

Supco M500 Megometer: amzn.to/4dTwuWT
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[@props-model-shop]

Just happened to my neighbor. Bad Cap caused unit Fan to stop working. Compressor goes into Thermal lock. He calls the AC repair man. The AC man tells him the Compressor is shot and that he needed a whole new systen at $22k.... I told him to wait for the motor to cool down and we replaced the Cap. All is working well now.

[@whochecksthis]

JEEEEZ! $22K? What did they quote him? A 5 ton variable output inverter heat pump? Hat is a massive price.

[@ttch2911]

If there is a delay circuit within the compressor, that might be the culprit that cause the compressor to go into a thermal lock. Mine happened as the delay circuit cause the compressor to start and stop a few times in a row and cause the compressor to overhead. Also Goodman compressors are junk.

[@TheQman69]

$22k?! We just had two new AC units and a new gas heater HVAC assembly installed on our 2500 sq ft 3 story plus basement house where the 3rd story has a separate blower and compressor than the 1st/2nd story and it didn't cost us that much. We paid almost half that much .. $12K and that's in northern VA (Loudon County) where the prices tend to be higher than the rest of the country too. I can now turn only the upstairs AC on at bedtime and not worry about wasting energy to cool the basement and 1st floor. This first month alone is already a massive improvement over last summer as we dealt with 90+ degree bedrooms on the 3rd story. It has even helped with our basement humidity too. We haven't had to use the dehumidifier once yet.

[@whochecksthis]

@@ttch2911 not all Goodman compressors are junk, but, yeah… those cheap rotary ones are… window unit level quality… Every motor I have ever worked on has a thermal overload switch that opens the common winding keeping the motor off until it cools down. I usually try running water on them to cool em down quicker, but I always tell customer it may need 24 hours to reset,so we can try and run it. Then determine WHY it overheated.

[@props-model-shop]

@@whochecksthis $22k would have been the cost if he had chose to use their financing for how many years to pay off... for a 3ton straight cool unit.

[@bikerbobcat]

Residential and Light Commercial HVAC guy here. Diagnosing a bad compressor is the VERY last thing for me because checking capacitors and contactors is just so easy. For only $90, that tool isn't a bad thing to have anyway. It's so easy to be honest. I'd rather be wrong than crooked. Get 3 opinions ANYWAY. Good video.

[@bran-qt7ds]

I had THREE different ac companies tell me my 10-year-old compressor was shot and I needed a new system. Finally a friend of a friend came and looked at it and fixed it for less than $100 by simply replacing pressure switch. That was 10 years ago and it's still running fine today. Anyone else would have just believed them and paid for new system, especially after three different companies saying need new system. AC companies are worse than used car dealers!

[@ronaldd.1355]

Does it apply to splits? (Panasonic A/C inverter 9000btu)?

[@cheezeball6109]

@@ronaldd.1355 I think in general, many HVAC guys have no idea what they are doing, and have no diagnostic skills, thus just recommending a complete replacement.

[@sprockkets]

Um, you replaced the pressure switch? You recovered the refrigerant, didn't vent any, and then had your friend braze in a new switch, and of course vacuumed it out and put the refrigerent back in? For $100 bucks?

[@jonathanocegueda7848]

It was probably one of the pressure switches that you tie in to the gauge ports that was installed.

[@sprockkets]

@@jonathanocegueda7848 which would be interesting because those are usually put in for those who need to switch off a fan motor because they need the a/c to work in the winter for reasons. No residential unit would have this.

[@elBusDriverKC]

You want to pull ALL your wires off first, then test. There's a chance that the MEGGER could be checking windings all the way back in your system. Even if the wires are disconnected on the other end, you don't want to be checking the insulation against wires hanging out of the compressor. Also, it's best to sand back the copper pipe on the compressor and use that as your ground.

[@AbNomal621]

In fact, the reason for the changing value is capacitance most of which is NOT in the winding.

[@knife_knut]

Correct!

[@kirkjohnson6638]

I was about to comment the same. If the black lead of the megohmmeter is connected to a bad ground, you may get a good (high) resistance reading but actually have poor (low) insulation resistance between coils and the case of the compressor. So definitely, disconnect all three leads (noting which color goes where) and then test between each terminal and a clean spot (lightly sanded) on the refrigerant tubing coming out of the compressor.

[@OUFan2]

I put in several Fedders units back in the early 80's. It had a Rotary compressor back then. Didn't have scroll compressors then. The Rotary compressor lasted a long time in AC's with short line sets, but did not last very long in heat pumps with long line sets. The rotary compressor always had troubles oiling correctly. You were just lucky with the unit in this video. I quit selling Fedders very quickly because of their compressor failures. I went to selling Rheem in the early 70's and they were great systems, but they didn;t have heat pumps at that time, so that is the reason I tried Fedders. When Rheem came out with heat pumps, I never looked at a Fedders again, I was an Air Conditioning contractor from 1972 till 2016 and then retired.

[@johneldorado]

I had an AC guy about 12 years ago tell me my unit sounded tired and it was probably time for a new one. Still running great after 12 years.

[@youtbe999]

Perhaps he was referring to his own wallet?

[@rickgarcia239]

Sounds like the tech was tired of making decent money legitimately & wanted to make the much bigger bucks being a criminal...

[@bikerbobcat]

I sound tired and need replacement too.

[@JackLucas-jh1eo]

You are the "Man." You are demystifying the ownership of a home a/c system. Thank you for your efforts!

[@Larry-yk5nh]

The manual for the insulation tester recommends that all leads be removed from the compressor at time of test. I would think that in some cases this could be important as other components still in the circuit could cause the lower 100 mega ohm reading you saw on the Goodman. The little tester does seem like a good idea. The manual says it applies 500 volts to the circuit at very low current and this is what is needed to properly do a test like this. Thanks for your video.

[@N-M424]

I agree regarding removing all leads. Also, the ground location being on a clean /paint free part of the case rather some other remove location is important to not receive a false high resistance reading. In the case of the compressor, directly to copper line seems like a good location.

[@Gus11445]

HVAC technicians stopped using these a year or two ago as we found out they can do damage to your unit. There's literally no reason anyone should be using this device over simply using a meter to ohm out the windings.

[@superspeeder]

Bad motor windings (checked with this meter) are only one of many things that can fail in a compressor. This only tells you if the insulation in the motor is good or not.

[@Charger1908]

I remember Fedders well one of my friends was a tech in the 60’s and told me that Fedders were very good. I do all my own work and actually I am a retired police officer and after retirement I went into plumbing and at times I helped the hvac techs so I learned a lot. I am an extremely adept mechanic and I have been for over 50 years. So now I guess I will do hvac when needed, I see I can already purchase a unit and have it sent right to my house. I’ve subscribed to your channel and we will see how it goes. Thanks!

[@hjc4604]

My Dad got a used 240 Volt Fedders window AC, probably 24,000 BTU from the company he worked for. He had an electrician friend run the electric and installed it in our living area/dining area window. It worked for probably 12 years until my brother bought them a central HVAC system. A 4 bedroom rancher with a full basement.

[@BartlettTFD]

I remember Fedders produced excellent window ac units back in the 50’s & 60’s They were made to last! What has happened to the quality we had back then?

[@inothome]

As long as compressor is functional, all three windings are connected internally. Testing terminal by terminal as shown is also testing whatever is connected on the other two terminals and then some. All three wires need to be removed and just testing one terminal to ground will test all windings. That tester is low current, but puts out 500VDC. So if there is something at the end of one of the still connected wires that can be damaged by high voltage, you just damaged it. Or if a fan motor is connected at the contactor with the compressor, you are also testing that fan motor and wiring. Which, if you get a bad reading and mis-diagnose the compressor bad, when in fact it was the condenser fan or wiring, yeah..... Not to mention, there are other things that can indicate a failing compressor. Doing an insulation resistance test is just one test.

[@jeremiahmiller7796]

Oh the best part about all of that is also scroll compressors due to the tolerances in which they are designed and where the refrigerant has migrated to in the system a good reading is still below the red bad marker on that tool. I can’t remember how low it is. I think it was like 5 mill ohms where that one bottoms out at 20 mil

[@inothome]

@@jeremiahmiller7796 The old rule of thumb was 1M Ohm per 1kV plus 1M Ohm, before insulation testers were measuring giga-ohms and now even tera-Ohms. So anything less than 1kV was always 2M Ohm. Now of course as insulation, materials and testers evolved you'll have specs in 100's of mega-ohms for low voltage and much higher for high voltage equipment. As always, best practice is to follow the manufacturer's spec. Like you mentioned.

[@tegra5971]

I agree… testing with any wires (=control circuit) connected could zap the control. You are doing an insulation test so everything has to be floating

[@bengordon7635]

how long are compressors rated to last ,, why do they not make the compressor easy to remove to install a new one like in a car ? why do you have to weld a new one in??????

[@inothome]

@@bengordon7635 They aren't hard to install, usually. Just need to solder the refrigerant lines, no welding, like most refrigerant lines are anyway. Cheaper, less materials and less chance for leaks when soldered.

[@mikeglasgow9618]

I helped a friends mother. He told me at work that it was the original unit to her home. When I got there it was a Chrysler Airtemp . Built in 1964. Had a bad contactor. Replaced, cleaned outdoor coil , lubricated outdoor condense fan, ,, STILL RUNNING TODAY.

[@frankl1955]

I did my first job in 82. Sent the wife for a 6 pack of beer and it was WARM. She said the little store down the street had the cooler go out. I had just graduated the Weat Side Institute of Technology for A/C but the owner told me not to bother 2 different companies condemned the compressor... It was a sticky current start relay

[@jacklabloom635]

I know of one Lennox combo outdoor unit ( Air conditioner/ natural gas heat ) that is 35 years old and still working. My late father-in-law purchased the unit 35 years ago. He died in 2022 and a grandson purchased the house. The grandson had the unit serviced, ( coils cleaned, Freon checked, etc. ) that old Lennox unit is still working to this day. The newer units just do not last that long. I have purchased several AC, Heat pumps, over the years. I have three Lennox AC units that are 23 years old. I have purchased York, Trane, American Standard, and Heil units in the past for different houses. My latest purchase was a Heil Heat pump, three years ago. So far so good on it. Only got 13 years out of a 5 ton Trane Heat pump. Replaced the outdoor unit with an American Standard unit in 2017. So far so good on it. I don’t know which units are better than others, but a good HVAC guy makes a big difference. My experience has been that Lone Ranger type HVAC guys, or an HVAC guy who has one helper provide better results than HVAC technicians who work for large companies, who employ dozens of technicians. Those companies have to meet huge payrolls, whereas the one or two person HVAC company is under a lot less financial stress to meet payroll. A good HVAC person does not have to advertise to get all the business they can handle. I found a great HVAC guy back in 2003. He was just starting out on his own back then. I have since used him for all my new installs and all repairs. I told all my friends about him. He got so busy he had to hire a full-time helper. He has so much business, he can pick and choose his customers. He is honest, reliable, and always does excellent work. He never had to use paid advertising. Word of mouth is more powerful in growing a business than any type paid advertising.

[@AverageJoesracingteam]

Your channel is great! You are saving people tons of $. Wish there was a channel like this that could save people from terrible doctors

[@N-M424]

Compressors that test bad according to this megger are not necessarily bad. According to Emerson, you can have a good compressor megger out to as low at 0.5 megaohms, where this meter will tell you 20 megaohms is bad. Additionally, contamination can cause low readings and if you remove the contamination, you remove the low reading and the compressor is fine. I suggest reading Emerson Bulletin AE4-1294 for more details.

[@ramonestrada38]

As an industrial electrician of many year's make sure you disconnect and isolate the motor from all possible wire insulation and capacitor leaks to ground. Also the ground connection should be very clean to avoid a high resistance and give you a false reading. Nice video 👍

[@Wade-LS1]

Using a meg meter to test windings with cold oil in the compressor can give you an inaccurate reading. Always take off all wiring from the terminals when doing any check and also test the compressor ohm value. The internal windings are treated with a lacquer coating and that acts as the insulator because the windings are in oil.

[@kieffersheatingcoolingv2.03]

Copeland states in bulletin AE4-1294 that megohm readings as low as 0.5 megohms to ground are acceptable. Besides the fact that this makes a scroll difficult to successfully meg (essentially impossible with a tool like the Supco M500 because it only reads down to 20 Mohms)

[@sbukosky]

Yes. This kid is giving bad information.

[@cincybeck]

I would completely isolate the compressor. And hook your ground to the component being tested. Testing like this it could be the compressor, the wires, the fan motor, the starting cap, or even the contactor.

[@damon20r]

It is checking the resistance between the windings and the ground. There technically should be no connection between the two when everything is perfect but when the coating on the wire in the winding starts to deteriorate it will begin to lose some of it's insulating capability and the resistance will begin to drop down from near infinite to lower values. That device is a ohm meter designed to measure extremely high resistances. At least that is how I believe it works.

[@MariosACandRefrigeration]

how many did he get wrong,testing like this.

[@inothome]

@@damon20r If you leave any leads on the compressor you are also testing whatever else is still connected to the compressor. Since the windings are all connected internally, you put 500V on the one terminal and it puts out 500V on the other two terminals and what ever is connected to them. So you are testing much more than the compressor and can even damage things with 500VDC.

[@damon20r]

@@inothome I agree, I would have completely isolated it as well to eliminate the possibility of one of those components feeding back to ground and giving a false condemnation. But there aren't any components in that circuit that are going to be harmed in any way.

[@cincybeck]

@@MariosACandRefrigeration @inothome Explained it better than I did. If you don't disconnect all the wires, the compressor windings are still connected to all the other components electrically, so if any of those have leakage it will show as a bad compressor when it might be something else in the circuit that is bad. Also if there is any electronics (control board/inverter) in the condenser unit they could be damaged by the megger.

[@jenkinsljenkinssquire9137]

Proof that the stuff they make today is $hit. 30 years old and still good while a 5 year old system is on the way out. We need a car guy like this HVAC guy.

[@ajs96350]

Goodman is pure crap.

[@SilverSergeant]

I'm not sure that 5 year old unit is suspect. I think not unplugging all the wires caused that odd jump at first....maybe capacitor discharge.

[@technodan3083]

For Toyota/Scion/Lexus, The Car Care Nut is really good.

[@dennisivakhov]

@@ajs96350not really. All the units are trash. Goodman is not bad as long as it has a Copland compressor. Lennox is trash indeed

[@jamminwrenches860]

Metal nameplate, made to last. Printed sticker nameplate, 10 year product.

[@icanreadthebible7561]

Good rule of thumb! Made in Mexico -- 5 years Made in China -- good luck getting it replaced under warranty.

[@billsimpson604]

Great point.

[@mediumrare9051]

Genius

[@markheaney]

They go on about recycling when all they should do is make things last. This is true for everything.

[@jugears1081]

In 1972 I saw a program on PBS titled "Planned Obsolescence". They are building them worse every year, intentionally. I am a mechanical engineer. I graduated in 1972.

[@spinb]

And they keep changing/outlawing the types of refrigerant. "For the environment," myass.

[@Shadow-7773]

@@jugears1081 So what are Homeowners to do? With all of the videos and other news about what is best! It seems there is no way out when buying a system, expecting it to last.

[@CC-hv5hk]

Wonder how many good reviews this guy actually have . We will never know how his customers really feel.

[@The1313jeff]

I have a 10 12 sheer Coleman heat pump and it is going on 27 years old and still running fine!

[@pctatc66]

yeah but your electric cost must be through the roof. Id hate to pay that bill

[@The1313jeff]

@@pctatc66 No it runs about $70 to $90 dollars a month in the winter to heat my house and the air condition is even much less then that!

[@chompnormski]

“They don’t build them the way they used to”

[@The1313jeff]

@@chompnormski And the fact that I only paid $590 dollars for everything the Heat pump and the air handler and all the duck pipe is another story by it's self! I had to give a guy $250 to hook the pipes up and thermostat And I installed the pipe and air handler myself! And it is still running today It is hard to believe what they cost now!

[@johngatsby1473]

​@@The1313jeffthey really aren't that expensive at all if you buy them yourself and then have it installed. These clown ass contractors are marking the equipment up 7 to 10k and acting like they got you a good deal.

[@SmooveBee1]

Trane SEER 10, two of them, THIRTY YEARS OLD here in Georgia; I can meg it out one day, if needed, but not needed right now; i have tested the temp in and out, pressure-checked it (I am just a homeowner), and calculated SUPERHEAT and SUB-COOLING both using temps from the Evaporator; these were each manufactured in 1994 and still running every year here in GA; I clean the condensers each year with Blue Dawn and lots of water; i don't cover the outdoor units (but i should and plan to "one of these days"). I have replaced caps and burned spade-lugs on the motor-run caps a few times, and I have replaced the fan-motors on each condenser unit, one time each, in 30 years.

[@UtwoBed]

Fedders made the best A/C units on the planet. I still have a little 5K BTU window unit that's literally falling apart but still works.

[@mtnest1226]

Love that silver KZbin plaque in the background,your videos are a great help for people who are overwhelmed by the hvac technology and of course some not too honest contractors

[@nohandsdan9353]

*Trick of the trade* run the blower fan while evacuating and pull shrader valves. Bigger hose does work. CRT are a must and purge slightly longer to be safe. As a home owner request a Manual J. If they look at you dumbfounded tell them to leave. A properly trained HVAC/R Company/Technician will provide you a report that verifies the system size they professionally recommend on your specific house features. Oversized cooling systems can lead to microbial growth in the home due to the system short cycling and not allowing the system run long enough to remove the moisture from the air. Bigger is never better in the HVAC/R world.

[@TooCloseSeries]

We all want you to install our new system. 🥰 I've used filterbuy your advertisement on this video. Got the exact filter I needed. Perfect. ( I was not paid to make this statement)

[@fernandodiaz5749]

I wish I could buy an ac system back when things were built to last, I paid to have installed 2 systems since a bought my house, and same scenario on the current ac unit on my house is relatively new and started acting weird already, now I know why, things are not built to last anymore.

[@wholeNwon]

OR you have had bad installations. Meticulously correct installations (the ONLY way to do it) are rare. The brand of AC system is relatively unimportant but the installation is extremely important.

[@fernandodiaz5749]

@@wholeNwon sadly reality that tells you how bad things are currently, quality degrading on both ends, products and skill labor.

[@dalesumney8806]

Thank you for your videos. I just replaced my condenser , A coil, line set and VTX. WE ARE COOL NOW.

[@jaguilar11009]

Thanks for all your help 🙏

[@TSGEnt]

Thank you for this demo. Very valuable tool. Learn something from you every time. Also, the bottom line, they don't make them like they used too. That and the higher pressures sure do shorten the life of these things.

[@wmcomprev]

While this tool can indicate a bad compressor, a good reading on it doesn't guarantee a good compressor. The motor may be hard to turn, causing excessive amperage draw even through the windings are good. Also, depending on the type of compressor, it may have bad valves in it; although, I suspect most are more of a rotary type that don't need valves. However, I'll agree that probably 99% of the time, if the windings are good, the compressor is good.

[@adrian-xy7zt]

Just stumbled on your channel and I love it. Keep those videos coming.

[@steveb6371]

That’s why I am not changing out my 1987 Trane unit.

[@user-dt3ol5jm4l]

Better off keeping it my friend

[@althouse2]

I live in an rv park in Az. Many of these Park Models have been here since before 1982. Many of the rv's still have the original carrier pancake 2.5 ton straight cool ac with 7.5 kw heat strips and Coleman Saguaro park model, and you'd be surprised as to how many are still rocking. Performing very well I might add. Some have new fan motors but many are still factory, when I do a performance check the run caps are still spot on, and many haven't even been serviced in yrs, I do many a coil clean and install a tri-dem 3ply filter to keep their ducts clean for many yrs to come I will be getting a mega ohm to further prove to my customers that their unit is still good and performing as it should, not one of my service buddies has ever told me about a mega ohm meter before. Glad I came across your video in upping my knowledge

[@onenikkione]

which rv park in Az?

[@handlesR4TrackingU]

I just updated my central heat & ac unit It was a Fedder installed in 1972. Replaced system not because the compressor failed but the ac system developed micro leaks. 3 in the last 4 years in different areas. With the insane cost of R-22 to recharge a 5 ton system. I couldn't justify the cost. So replaced the whole unit with the help of your videos. The $ saved on utilities and installing it myself. It will have paid for itself in 3.5 years. Thank You for the help. I could not have done it without your videos. Keep up the great work.

[@QuantumRift]

we have two bryant heat pumps, and I keep a couple starting caps handy in my tool kit.

[@terrylarson7596]

There are a few independent HVAC mechanics that will inspect your system and advise you honestly. My buddy just got a new furnace because his combustion fan was bearing was dry and seizing up. I replaced my sisters combustion fan for $350.00 in parts. Some businesses are directed to sell HVAC systems, they will say stuff like " I could fix this but something else could go next week"

[@ThangNguyen-gi6sk]

I wish u live near me! U are such honest hvac tech

[@johnlegarre3667]

Fedder was a huge manufacturer of window/wall units in the 50s-60s.

[@t.d.harris1311]

New stuff is made to fail, my grandmother had a GE refrigerator that was over 50 years old, it ran until the house got flooded and water got inside the compressor area and the people who help clean up threw it out.

[@jugears1081]

In 1972 I saw a program on PBS titled "Planned Obsolescence". They are building them worse every year, intentionally. I am a mechanical engineer. I graduated in 1972.

[@EnigmaticJack]

You want the terminal posts to be warmer than ambient temp when checking. Also pull all the wires off before testing. And lastly, scroll compressors react differently than regular reciprocating compressors…they’ll read low or bad when they are fine due to limited clear to can from windings. You gotta know these things if you’re gonna “teach” people

[@TrendyStone]

I had to replace 3 fan motors over 20 years. Eventually when the unit died we realized the wrong jumper was used on the circuit board when it was originally installed and my fan had been running too fast according to the service rating for it's entire life! That explains why I kept going through fan motors. Luckily they were only about $30 each.

[@GreyRockOne]

Good info here! I've always been my family and neighbor mechanical and electrical handyman, cars, electronics, home appliances, you name it. I've done all my own HVAC work too. You just need a good attitude, patience, common sense and a mechanical aptitude. I always love to watch your videos for up to date info! Thanks!

[@wholeNwon]

In my case, I bought an AC textbook, read it, worked on my own systems, took the licensing exam, aced it and was no longer an HVAC "service" victim.

[@xaviercruz4763]

How much would an air conditioner at good price new or used cost for 1 acre of land or ~3000 square meters for a greenhouse? A unit that can lower temperatures to 2-3 Celsius or 41f

[@SilverSergeant]

Unplug all the wires before testing. This was not proper technique.

[@Watchyn_Yarwood]

Neighbor called me to come to her house. HVAC contractor was trying to charge her $320.00 to replace a wire on the condenser. I disputed the charge and fortunately the contractor tore up the work order. Two days later, she called me and said it had stopped blowing cold air. I walked over, looked at the condenser and the wire he replaced was burned up. Again! I told her wires don't just burn up. Something caused it. I looked at the contactor and saw it was completely burned. I went to a HVAC supply house not far away and bought a new contactor for $16 and new capacitor for $15, replaced them and the burned wire and it's still working three years later.

[@Buc_Stops_Here]

Actually, had different problem. it was a combination of the compressor and capacitor. It was showing 2 volts below spec. He suggested I buy an Install Hard Start Kit. This helps the compressor start up and come up to operating speed quicker. The start assist reduces winding stress and the production of winding heat, saving the compressor from additional strain and increases the life of the compressor. The heat pump is now 12 years old, so if I get another 2 years out of it of year-round usage in CT that is a pretty good life.

[@chrisr6206]

Oh yeah, the unit is working fine and is about 21 years old, but due to this VID, I purchased the M500.....Tucson, Az. area (Sonoita actually).

[@ttch2911]

You are checking the insulation level between the winding of the compressor and the ground using the ohmmeter. Higher resistance means better insulation to ground so less likely to short out. Insulation generally don't deteriorate unless the insulation material are not up to standard or compressor overheated numerous times causing the insulation to break down.

[@davep2115]

Dirty freon is definitely not going to break down winding insulation. Lol

[@rogercook2292]

ohmmeter that uses higher voltage to check motor windings is a very good tool, but limited in scope of what it can tell you. many other issues with electromechanical devices that won't show up on resistance tests but kudos for giving average joe homeowners some direction in troubleshooting. I think a lot of consumers don't know the huge scientific and physics principles at work to remove the heat from the air inside of a structure and expel it outdoors (or vice versa in the case of heat pumps) and anything that can be done to demystify the process is always good.

[@jamess1787]

The capacitor thing almost got me, i hired another company (family friend); he is wasnt even sure. He threw a jump start cap on, and jt held for a month. I bought a new cap, swapped it out. Boom, 5 years and still going. 🤜🤛

[@diyhvacguy]

Niiiice bro 🤘🏼

[@DavidAnderson-se1or]

Could the Supco also be used with a smaller mini split system to check the compressor? Your channel is one of the best on YT. Very informative!

[@bryanst.martin7134]

I had an issue once, called the installing company and they replaced a fuse on the control board. It blew again so he installed a new control board. Fuse blew again. I popped the side cover off of the condenser and noticed black scoring on the edge of the Cap. The low volt control wire had chaffed and grounded against the cap. A piece of tape and zip tie to keep it off, new fuse and voila! Called the company for a refund. They weren't happy. No AC in Fl summer made us unhappy. Fair enough.

[@silasketgaskets8709]

some good videos on how they rebuild a/c compressors and can see theres more that can fail besides the windings. most common is burnt capaciter and easy to replace. on an old mini split the remote receiver board and indoor pcb failed. i replaced them with a single universal pcb with onboard receiver. works great ali express about 25usd. worth using an under / over current protector as the expensive pcb's can die. also be very careful with caps as they can store electricity even if power turned off. i use insulated gloves and tools

[@barryinkpen6026]

If you're going to meger the compressor you should remove all wires and then do your test on each terminal. Your test method could pickup carbon dust on contractors etc.

[@TheDarrlelennis]

Just ordered it on Amazon

[@Clif_Brown]

Great informational video!

[@rogerdirks947]

If I were doing the testing, I would have all 3 wires disconnected at the compressor during the whole process. With only one wire disconnected at a time, you would be reading through the very low resistance of the windings and back into the capacitor and contactor,which can give a false low reading on the megohmeter.

[@horaciosalazar9963]

Hi, nice video. Thanks!!! Saludos desde Tampa Florida

[@jons2447]

Many "THANK YOU!"s to you , sir! Dave, you *ROCK!* I'm so glad I follow your channel because so many people are rotten crud, liars, cheats, & thieves. Your honesty and character are a testament to you and your parents. May you be blessed for following our Creator's guidance. I've noticed that you try to help people protect themselves from evil ones. I commend you for your efforts & wish you the best. Have a GREAT day, Neighbor!

[@edwinbarahona4486]

Thank you for the advice 🎉

[@noelelnolo9642]

As always, great videos and excellent information. Unfortunately, there r so many con techs everywhere!!

[@JT-lq4yd]

This tester looks for electrical "leaks" in the electrical conductors insulation inside the compressor. Nice! The compressor on my unit sounded like a rocks in metal can being shaken😅.

[@Ratlins9]

@JT-Iq4yd Thank you for explaining what this tester does.

[@everestinspections9088]

Great advice thank you

[@redneckminer9164]

Super cool! Does this work for variable inverter compressors as well?

[@mkmac9539]

Thanks so much for this info. I will get one of these and test.

[@bobboscarato1313]

I sold Fedders A/Cs. Long ago in the NY metro area!

[@MrJoep71]

love those old systems, they were built like a tank. I have a property with over 100 Gaffers and Sattler units that are 1971 models, I've never replaced an unit there. New systems are lucky to last ten years these days

[@Gerald-do9yg]

Gaffers and Sattler! Long time since I'd heard them mentioned! Glad to hear of their reliability.

[@bernardaflores1720]

Great video, does the Megometer also check the compressors for refrigerates and freezers etc??

[@carguy4243]

My next door neighbor has a 1979 Fedders that still works fine.

[@BillBabyEscapades-bp4sf]

Love these videos, they fatten my wallet every time one comes out!

[@ronroth8788]

My blower fan on the air handler was not always coming on. The AC man says I needed a new system. I replaced my thermostat (15 years old) and all is well.

[@MrPoppyDuck]

Tha start capacitor went out on mine. To be fair, that central AC unit was built in 1967 so I cannot complain. Ended up replacing the entire system a few years ago as everything else was original and would no longer keep up on really hot days.

[@wholeNwon]

Interesting. Why was it no longer "keeping up"?

[@MrPoppyDuck]

@@wholeNwon Unsure. Coils were reasonably clean for being 50 years old. System was charged. Evap coil drain tray was rusted away with some of the air handler so it leaked and damaged the garage ceiling. Was bittersweet to see it go as that system was built like a tank.

[@charlescoffey9523]

While I agree that often it is something like a capacitor for the reason a unit does not start. Electrical shorts, which can be tested with a standard multimeter, granted there will be a few cases where the short is not seeable at 9 vdc but those are very rare. But there are other factors beside this, a bad valve in the compressor would show a good compressor in this type of test. A better way of checking for electrical issues is both resistance of windings and current draw compared with exchange temps.

[@jmead6121]

back in the 70 , 80 90 we never ever pulled an Vacuum on R 22 .....bk then it was purge & go

[@Lettuce-and-Tomatoes]

I have a home warranty through State Farm that covers my home HVAC system. The deductible is 500 bucks. It would be extremely interesting to me (and other home warranty holders) to see a video on how to troubleshoot and repair 500 to 700 buck problems. I’m not too concerned about work going over that amount because that’s when the warranty I’ve been paying for kicks in and I’ll let a pro sort it out at that point.

[@EnigmaticJack]

You do understand that what constitutes a $500 problem in one geographic area doesn’t necessarily amount to the same in another, right?

[@sweaner]

Fedders! the very first house that I lived in as a child had that brand. We are talking 1960!

[@hjc4604]

While I might use this to indicate if further testing is needed, I probably wouldn't condemn a compressor without checking further. Many "condemned" compressors tested at the factory show nothing wrong with them. "Studies performed by Copeland have found that compressors with megohmeter readings as low as 0.5 megohms still pass the hi-pot. There are many factors that affect megohm readings including contaminated refrigerant, oil level, refrigerant in oil and current leakage through electrical fusites or terminal plates. As mentioned earlier a single megohm reading cannot be used to condemn a compressor since many other factors are involved. However, limits can be placed on megohm values that dictate action be taken. Copeland has found that these limits are related to the rated voltage of the compressor. Megohm values equal to or greater than 1000 ohms per volt are probably acceptable. For example, a 460 volt compressor might show a megohm reading of 460,000 ohms or 0.46 megohm. Compressors with rated voltages of 208 to 230 volts would then be operable at megohm values of 0.208 to 0.230 megohms; for simplicity, Copeland has set the limit at 0.5 megohms before a compressor is condemned. Figure 1 shows the required procedure for checking compressors with a megohmeter. New compressors that have never been installed will not need any system clean-up procedures so long as the megohm reading is above 0.5. A baseline reading must be established for comparison purposes and since this is its first reading this will be its baseline"value. www.graycoolingman.com/uploads/1/0/6/6/10667336/copeland_4-1294.pdf

[@DavidWarshawsky-kr1po]

Don't forget to clean them which is a must

[@hinspect]

I haven't thought of Fedders for years! 🤔

[@rogerhammel429]

Try ur test by putting the ground clip on low side copper near compressor!

[@woodwardbrandon]

My system is an 85, started looking at replacement options. It still runs reliably. I clean it twice a year. I wish things were still made as good as they used to be it a shame.

[@azcamperjohn1079]

I used to use this when I first started in the industry, found it to be 50/50 when saying a compressor was bad. I would just tell the customer that one of the test showed the compressor was going bad so not to be surprised if it died suddenly. never sold a customer a new system or compressor based on that reading alone.

[@johndavis2938]

I saw units like these in the 90s in Germany. This is the first time I've seen the design here in the US.

[@mistytharpe3991]

No school like old school. The antique rocks 😂

[@james10739]

I assume the reasons the insulation breaks down is possible thinner or of a lesser quality but aside from that is heat definitely anytime it goes into over temp

[@patriot0971]

In our neighborhood bunch of us started to get written estimates and the diagnostic reports etc and posting those to our community facebook page. Naming and shaming these crooks was the best thing that could have happened to the residents and honest services companies. I had a company threaten a legal action about sharing the estimate and I happily asked them to go ahead, as I will request a civil jury trial and request discovery. That guy shut up so fast.

[@jetdigital]

Fedders was the best Got a 5000 with old refrigerant and it cool a complete ranch house. No kidding Like an icebox and I still use it Thats why it still tested good Maybe oil filled cap I would like to dee the the difference of the electric draw though.

[@dougdorrer4622]

R22 is no longer manufactured. R410a is being phased out, and the newer R32 and R454b are not readily available.

[@ckelly5141]

Great info. Dave. Hopefully we all last longer than our expiry date.....right Dave?

[@billbradleymusic]

No such word... Expiration date is what you meant. But you knew that.

[@nohandsdan9353]

Bro you better be careful... this is whistle blower kinda stuff. You better hire some security guards 😎 great video and very informative!

[@natevanlandingham1945]

Yep i have heard of Fedders. Im not an HVAC guy either.

[@robertmunguia250]

How about the heater core that is wrapped around compressor? Testing it?

[@frankroper3274]

I worked for the state and most anything can be repaired. You can replace a condenser but most service co's will sell you a whole condenser since that is the only way they will guarantee it.

[@gotchaplumber]

Good info.

[@IM35461]

To perform a DC Insulation test on any motor you need to disconnect all the external wires and then perform the test. Otherwise you are testing the motor and the external wiring through the windings of the motor. Also if the unit has any electronics you run a good chance of damaging them with the high voltage.

[@bobrustigian4637]

Hi there, great content. Can I use a good quality DVM and get a resistance reading that way? I already have two DVMs and hate to buy more gear if I don’t have to, thanks.

[@wilsoneashoian5789]

U R awesome. I was an electrical engineer, and we did power factor insulation test of hundreds windings using Megger and Doble. It is a best test

[@charleshenderson1174]

Thanks