@DrZarkloff Hey I have a 200Ω on my meter and i know its used for testing the windings on compressors. My question is what it the 200kΩ used for or if you can make a video using kilo ohms testing because we didn't use it in school. Thanks
let me tell you something DR. yesterday I check a single face compressor and I did the same procedure and my meter tell me c-s= 2, c-r = 10 and r - s = 11 and tell my bose the compressor windings is together. what do you thing ? dr and thank you you help me a lot.
hi dr I have ice machine problem; I fix electric problem but the sistem is running the compressor is very hot and I put my gauges in low side the pressur is high 117 pisg, I have friend told me is low charge, but another told me not is over charge recovery all the freon charge again , What do you thing ?
@gleelover1fan It's necessary to recover all of the refrigerant from an ice machine and to weigh in the charge to get it right. Ice machines and other small appliances are critically charged.
thank you for the info, I'm currently in the Air Force and training for HVAC/R as a beginning job, I really enjoy the HVAC/R career field, and genuinely appreciate more experienced technicians posting videos on YouTube.... as it makes it easier to understand, thank you for taking the time to make this video!
i have a question dr. z..i recently checked out a comp (r22, single phase)doing this method and comp seems good. i hooked my gauges and read about 100 psig in my suction and about 225 on my liquid line. it doesnt seem to want to go down after i tried to recover some refrigerant thinking its overcharged but cant seem to get to the correct psig (suction) which is about 70 psig n every time my t stat cuts off on set point it doesnt turn back on, wut do u think i should do?? is my comp bad?? thnks
@alexfromthevalley You need more info to know what is wrong... What is the oat? what is the dlta t indoor coil? did you try to calculate the subcooling and superheat? what is the compressors amp draw? 100 deg coming in may not be too high if the space temp is high and the charge is low.... like I said you need more info to make a correct diag... it could be the vavles are leaking and or you have an unloader open or a hot gas bypass or a desuperheater problem. or other problem.
Hey im suppose to meet with a counsler tomorrow about going to school for HVAC...i notice in craigslist the requirements that you need a clean driving record..Although i haven't gotten a ticket in over 10 years i still have this reckless driving in my record because it was misdermeanor...Is this gonna be a problem for me?
@DrZarkloff k thanks....im starting the hvac program in 2 weeks...although i think the wreckless driving might be out of my driving record because it's been over 10 years...i looked it up and it said it stays in your record for 7 years so hopefully it's gone...thanks for the reply..
@savator408 I just finish school for HVAC/R this year of March 17 E.P.A 608 Certified Universal. It feels good to have those papers. Now I'm working,but they didn't ask me about my driving record. I guess every company is different. I have a speeding ticket on my record and they still hired me.
@eastsideatlanta so your doing hvac work now? if so that's good for you...im starting next week and im already on craigslist looking around the states to see if they are hiring for HVAC jobs..and all the states in the US are hiring for HVAC work...i even checked out Atlanta and they have a few also...i live california but its a bit expensive to live out here...so i was looking outside of California i think Atlanta might be a perfect place or even Denver...
Hello Dr Z I have been watching your videos with great interest. I am currently in school learning Hvac. I need your help I was having a discussion about charging an AC system. I have instructors who say you have to use superheat all the time to determine the proper charge. I have other instructors who say if the ac is equipped with a TXV valve you charge by sub cool Who is right
My name is Tom Higgins
Email is tommy33004@yahoo.com
Could you please respond and maybe do a video explain things
Hello Dr Z I have been watching your videos with great interest. I am currently in school learning Hvac. I need your help I was having a discussion about charging an AC system. I have instructors who say you have to use superheat all the time to determine the proper charge. I have other instructors who say if the ac is equipped with a TXV valve you charge by sub cool Who is right
My name is Tom Higgins
Email is tommy33004@yahoo.com
Could you please respond and maybe do a video explain things
@rick601a You should have no continuity to ground on any of the compressor terminals with your meter set to the highest ohm scale. I have seen compressors run with slight shorts to ground but they don't run long.
In school, I remember that a compressor can (unintentionally) run backwards. On a three-phrase all you do is switch any 2 terminals. How can you tell in the compressor is running backwards? I know it takes almost no time to ruin the compressor if running backwards. What do you do if a single phase compressor runs bakwards?
@BGreenHVAC Scroll compressors will make a bad sound and the high and low pressures won't change if it's running backwards. It doesn't matter which direction a reciprocating compressor is turning.
@medahenderson1008 No, if the resistance jumps high that is a winding about to fail as in about to open up or it could be a bad connection with your meter leads, or a bad internal protector. If the resistance is low that is a winding to winding short.
For single phrase compressor. There is no mark on compressor. How can you tell which one is run,common and start ?. How can you tell a new compressor which one is high side and low side ?.
@khonglap The terminals on a compressor is marked at the terminal block and the larger tubing is the suction side and the smaller tubing is the liquid side.
Can someone please help me my house has no heat having fan problems. Please watch my video that i uploaded and give me some pointers please. I would really appreciate it.
Dont get me wrong as I think your great and most of your vids are correct but you should always teach to turn off the power supply first and then test the terminals before you touch them, you should also have insulated screw drivers and plyers and you should use the ohms scale on your field piece meter and you should test each winding to earth.
My bad I couldn't believe it was actually a thousanth of an ohm!! Bro in electrical sense this is neglible or useless. Why because even the soundness of the battery in your meter can affect its reading by a few fraction of an ohm. Not pressing the test leads as hard as the other can make you change the compressor for nothing!!
Bro I don't mean to be rude but if you put the two test leads together, you will get a very low reading like that. That means the winding have almost no resistance to DC current. Tightness of the test lead on the meter, how hard you press the lead on the terminal, how clean the terminals can actually make a difference of a even a few tenths of an ohm. You base the reading on a hundreth of an ohm!
Bro I don't mean to be rude but if you put the two test leads together, you will get a very low reading like that. That means the winding have almost no resistance to DC current. Tightness of the test lead on the meter, how hard you press the lead on the terminal, how clean the terminals can actually make a difference of a even a few tenths of an ohm. You are base the reading on a hundreth of an ohm!
Hello Dr. Zarkoff...I have a problem with a compressor that electrically is good when i ohms it...but is falling mechanicallly because is tripping the braker and I know is the compressor becuase I unhooked the voltage to the compressor and the fan was working...my question is if the compressor fails electrically would it trip the braker or not?
@catrachomg Mechanical failure doesn't always mean that the breaker is going to trip. For example: if the motor shaft breaks, the compressor won't do any work and the motor will just turn without a load.
@catrachomg It depends, does it trip as soon as the unit calls then yes, if you can start the unit check the amps with a amp clamp then compaire to the name plate data. thare is two amp readings RLA running load amps. LRA locked rotor amps. if you read locked rotor amps the compressor is gone. When you did your ohms check did you check form each one to ground to see if the comprssor is shorted internelly?
I'm not writing this to hate on you in any way, but I just think it would be wise to announce in your video that this is intended for professionals. I went to two years of school and took a state license exam, so that I would know the proper technique and have the proper safety precautions in mine. The home or business owner does not need this information, or at least to take it lightly. Watching you do something and then thinking they know what your even talking about, should not be done.
@DrZarkloff You do know that on the fieldpiece and most other meters that continuity is not the same as resistance. You want to measure in the OHM setting, this is to ensure an accurate reading. Plus you didn't check these compressors to ground. I'm not trying to pick this to death but who is this video intended for? Amatuers or professionals?
Never measure the resistance of compressor motor windings at the compressor terminals, especially if the compressor motor is suspected of being damage. Certain types of compressor motor electrical failures can damage the compressor terminals. Touching the damaged compressor terminals, especially if the compressor is under pressure, can release that pressure, causing injury or death. Always recover all the refigerant before testing at the terminals if you have no other choice.
hi,you know you're my teacher?you are really good thanks for all,i will ask you a million questions but one at a time,its real that if i run my ac all day long its more cheap than stopping in 8 in the morning and then start up at 6 pm?i live in florida heat
@carlitosgy6 Thanks for watching my videos. I've always found that setting back the setpoint on the thermostat when you aren't at home saves electricity, hence saves money.
@Nspect I was a HVAC tech for over 10yrs and still work on the side for myself as a tech. I always ohm out the compressor at the terminals. As he says this eliminates any false readings through the wiring. As for the terminal blowing knocking your hand into a live circuit you should NEVER have the power on when ohming a compressor at the terminals in the first place. You can also do a continuity check to see if the compressor is shorted to ground.
DrZarkloff I have a question. In the video you pull the compressor leads off of the terminals directly to ohm them out. I have been always told that you should never do this unless the charge is pulled out of the system because, the terminals can shoot out and blow your hand off while the system is under pressure. I'm only a 4 year tech from So.Cal. Just wondering if that is a myth or true what they say?
@IndieBraah You are correct. It's not a good practice to directly push on the terminals with the leads of your meter while the compressor has pressure in it. If you think about it, the terminals are held in place by a bake-o-lite (plastic) insulating material. Basically it's a plastic plug. If the seal around that plug is weakend, and the pressure of you pushing on it while testing for continuity, the terminal plug could blow out.
@IndieBraah Part 2 to my response... There used to be a training video years ago put out by a compressor manufacturer that showed the terminals blowing out of a compressor. As you can read from below comments, there are people who claim to have experience and offer both points of view of how to check for terminals. I can tell you that I teach HVAC for the USAF and USN and we teach never to check directly on the terminal plug. Why tempt fate and end up a statistic? That's my motto...
yes i thought i turned off the power two days ago on a three phase 460v packeg unit.and the next thang i no i was stuck to the unit and yelling at the top of my lungs..not fun thank god i have some waight on my bones cus i was on able to pull my hands off.. scared the shi_ out of me. so pleas all tecs and installers dont trust outher pepoles work or word check for voltege..thnx
@baydestrian84 A shock from a 440v unit is no freekin joke. Could cause death or at the least serious burns. I use one of those non contact probes just to be sure the power is off. I almost shocked myself on a attic air handler the other day on a multi unit building. I shut off the wrong breaker, good thing I checked with the probe before putting my hands in there.
Assuming voltage is not present is not a good idea. Testing and double checking could be a life saver for you or anyone that gets involved with electrical projects. Getting hit with 277 VAC usually ends with you running in circles calling out the voltage like a voice activated multi-meter. And 460 VAC will shut you down quickly. Take care baydestrian84 and DrZarkloff is a Professional that would never lead you to believe assuming is a good idea.....Sea Breeze
Look at 1:47 in the video. You have your HS33 Fieldpiece meter set on continuity. You have a tone, a light, and the knob is pointing to this setting. I have the same meter. What should you be reading on ohms on a scroll compressor let's say 4 tons?
@robertcyders I'm not sure. You could test the scroll compressor in the same manner as long as it's single phase. Three phase compressor should ohm the same between each winding.
I have installed Petra chiller its expansion valve got stuck 05 to 06 times in two years there is installed Danfoss SS body valve, Please reply what cause of getting stuck the expansion valve.
@2170509 The valve could have got stuck if a piece of trash clogged the orifice. Sometimes, an oil flood back can simulate a stuck valve. By the way, I prefer Sporlan expansion valves. Enough said.
I have installed 1/2 hp compressor Danfoss 134 a in fridge its getting to heated and compressor return came means suction line temp. came at above 20 psi I read in book at 80 Fahrenheit, suction allowable temp 30 to 20 Psi so 20 psi pressure of suction line is it suitable? Please Reply Dr. Zarkloff
@2170509 You should just weigh in the refrigerant charge. Don't be too concerned with the suction pressure unless it's too low and the line is icing up.
were those compressors under pressure because my teacher say's that checking ohms at the terminals on the compressor might blow out on you. What can you tell me about that
Hi i was adjusting my swing setting and wondering my unit runs about 14min on and 14 min off . 100f out side. i know theres alot more to factor in but what do you think about that? would it be more efficent to run on say 10 min ? how long should it run at that outside temp aproxx? thanks
@juanater2000 It should be running until the indoor temperature reaches the thermostat set point. Your system could be shutting off on high head pressure. Try cleaning the condensing coil.
Resistance measurement cannot determine a shorted coil. I mean any type of coil specially the ones in a compressor. Although it can determine an open winding which rarely happens. A ring test can be performed using an oscilloscope and a signal. Even then it is not 100% reliable. I don't even know why some technical books have sections in measuring Resistance in coils. It is useless and a waste of time and may lead to confusion.
Hi, Please make me know, can we charge the gas in the system with gas? when we know TR of the system I am talking about gas quantity in weight I know when the system RFT increase gas quantity also increase but is there available thumb rule when capacity so and so then quantity so and so.
An open in the winding will help you with DC resistance measurement, but if there was a short you would not be able to measure it with a regular ohmeter.
When you use an ohmmeter you are only measuring the DC resistance of the compressor coil which are very low. Remember the winding act upon the 60HZ cycle of the house current!! You have to measure IMPEDANCE which is not the same as resistance!! You have to know the size of the wire the number of turns, the size of the loop and what the core is made of then the frequency of the current which is 60 HZ. Measuring DC resistance on compressors are useless. Now coils that has many turns its ok.
You are only measuring the DC resistance of the coil. I would use what you call a ring test. It is the same way we determine a bad flyback transformer in a television. Note that coils characteristic are measure in IMPEDANCE not in RESISTANCE which is what your meter is reading. Coils IMPEDE current they do not resist them. I think AC technician do not understand enough about electricity. Even the ones in the field for a long time.
It's working but condition is that when compressor cools it starts smoothly but when compressor have been runing for long time electricity goes out when electricity comes back after dealy the time it does statr because it gets hot. after delaying 05 to 10 minutes it starts.
It's working but condition is that when compressor cools it starts smoothly but when compressor have been runing for long time electricity goes out when electricity comes back after dealy the time it does statr because it gets hot. after delaying 05 to 10 minutes it starts.
@2170509 Not to step on the doc, but might I suggest you have a restriction in your line. Possibly at your TXV. It would make sense if your compressor were not getting enough refrigerant intermittently. It would shut down, cool off then restart. If I were you I would try and blow out the lines with nitrogen.
Sir, I have installed the compressor which gets so I checked the compressor so it's C-S = 0.024 Ohms , C-R = 0.005 & S-R = 0.029
I found that compressor is electrically O.K as per your teaching but make me know that C-S ohms is too high as compare to C-R. Is this reading is sufficient?
Sir, I have installed Mitsubishi Packaged type split unit Model # FDC81BA & FDC101BA its compressor have changed 02 times converted Copland so please send me the quotation of Mitsubishi Compressor.
And make me know I got the new compressor installed after installation and commissioning of the compressor it was out of order mechanically than we got it repaired for few days it operates in sufficient condition but it has got out of order mechanically again. So what is the problem it h
Hi, Ilike your vids, I am actually wanting your input on my ac unit, my evapoators are freezing up, and I hooked up the gauges and the readings are the same with the compressor off and running. checked the ohms and read good. but is the compressor bad mechanically? even though the evap's freeze?
@extreme383 First, if the evaporator is icing up then you're going to get different readings when the system is on than when it off. It just doesn't make sense to me why you'd get those readings.
You have tough me how to check compressor electrically but How should I check the compressor mechanically both types Hermetic Sealed and Semi Sealed compressors.
@plaebslayer If you have anything other than OL (open line) between the windings and the compressor housing and suction line, which would be ground, you have a bad compressor.
@HVACTECH4105 Yep most times when a compressor burns out it shorts to ground. And if the terminal block blows clean out of the compressor and their is black oil all over the interior cabinet it will be really obvious lol! ARRRGG I hate it when that happens.
i've a condense leaking between copper fin and lumnium , where is manufacture made joint solder, any way can we fix it ,by reg. copper solder? thanyou for any advice mr. drzarkloff
i have my second interview on tuesday as a trainee HVAC eng, your vids are great im taking notes and trying to remember as much as posible if you have any tips for me for my interview that would great.
you sir are my new best friend
mexicakam 4 days ago
@mexicakam Thanks for the compliment.
DrZarkloff 3 days ago
This has been flagged as spam show
Very helpful
nimoojan 5 days ago
good
sai27hanif 1 week ago
Whst ohm model are you using...I need to buy me one of them babies
Aagtx 1 month ago
@Aagtx I have the Fieldpiece HS36.
DrZarkloff 1 month ago
I aways test first to see if the comp motor shorted to ground,if it is than I don't have to do any further testing.
fonephat 1 month ago
@fonephat Good point. I do the same thing.
DrZarkloff 1 month ago
Very helpful video
kameronasalaulau 2 months ago
haha i love how he sounds like bill murray
superman2261919 2 months ago
@superman2261919 lol. I've never been told that. Cool.
DrZarkloff 2 months ago
im getting a high reading on low side the high side is giving me 0 reading what do you think is goin on with compressor
dianemarie909 5 months ago 2
@dianemarie909 Does the pressures equalize when the compressor turns off? If it doesn't then you probably have a bad check valve.
DrZarkloff 5 months ago
@dianemarie909 you either have a bad gauge your using or some kind of restriction in your gases thats not
normal
MrGeorgeda123 4 months ago
@MrGeorgeda123 I once had a gauge hose resticted caused that problem.
fonephat 1 month ago
@DrZarkloff Hey I have a 200Ω on my meter and i know its used for testing the windings on compressors. My question is what it the 200kΩ used for or if you can make a video using kilo ohms testing because we didn't use it in school. Thanks
ramirez509 5 months ago in playlist hvac
@ramirez509 It's a higher scale for ohming shorts to ground as in testing the insulation.
DrZarkloff 5 months ago
@DrZarkloff Could you make a video using kilo ohms on a compressor? ;0)
ramirez509 5 months ago
how to ohming Honeywell Smart Valve
1232saulius 5 months ago
@1232saulius I don't have one to ohm. Sorry.
DrZarkloff 5 months ago
let me tell you something DR. yesterday I check a single face compressor and I did the same procedure and my meter tell me c-s= 2, c-r = 10 and r - s = 11 and tell my bose the compressor windings is together. what do you thing ? dr and thank you you help me a lot.
1818carlomagno 6 months ago
@1818carlomagno Thanks for watching.
DrZarkloff 6 months ago
wen i on my aircond,,,the compressor run in a sec then trip all over my house?? y is that happen?
bhc3046 6 months ago in playlist Air Conditioning Repair
@bhc3046 The compressor is probably short to ground.
DrZarkloff 6 months ago 2
hi dr I have ice machine problem; I fix electric problem but the sistem is running the compressor is very hot and I put my gauges in low side the pressur is high 117 pisg, I have friend told me is low charge, but another told me not is over charge recovery all the freon charge again , What do you thing ?
gleelover1fan 6 months ago
@gleelover1fan It's necessary to recover all of the refrigerant from an ice machine and to weigh in the charge to get it right. Ice machines and other small appliances are critically charged.
DrZarkloff 6 months ago
thank you for the info, I'm currently in the Air Force and training for HVAC/R as a beginning job, I really enjoy the HVAC/R career field, and genuinely appreciate more experienced technicians posting videos on YouTube.... as it makes it easier to understand, thank you for taking the time to make this video!
davideidsvoog 6 months ago
these are some great videos dr.z! thanks for making the time to make them.
bigguysa210tx 6 months ago
@bigguysa210tx Thanks for watching.
DrZarkloff 6 months ago
question for dr. z
on a home refrigerator compressor,,,, can the freezer get down to 10 degrees and still have a bad compressor
the refrigerator side won't ever get below 40
amen77787 6 months ago
@amen77787 It's possible that the compressor might be the problem. I'd look for other problems like a dirty condensing coil.
DrZarkloff 6 months ago
your good i just wish you werent so boring
BlueToad2222 7 months ago
dr z keep up the cool vidz!!!!! very nicely explained!!!!!!
jimbola77 7 months ago
thanks for the advice
ToledoApplianceGuys 7 months ago
i have a question dr. z..i recently checked out a comp (r22, single phase)doing this method and comp seems good. i hooked my gauges and read about 100 psig in my suction and about 225 on my liquid line. it doesnt seem to want to go down after i tried to recover some refrigerant thinking its overcharged but cant seem to get to the correct psig (suction) which is about 70 psig n every time my t stat cuts off on set point it doesnt turn back on, wut do u think i should do?? is my comp bad?? thnks
alexfromthevalley 7 months ago
@alexfromthevalley you have a no pump compressor bad compressor
REDDOG9608 7 months ago
@alexfromthevalley It sounds like the compressor isn't compressing properly. You might want to replace it.
DrZarkloff 7 months ago
@DrZarkloff Great video Dr.Z Thank you for taking your time to help us.
abevazquez 7 months ago
@DrZarkloff Great video Dr.Z Thank you for taking your time to help us. Have an awesome day!!
abevazquez 7 months ago
@alexfromthevalley You need more info to know what is wrong... What is the oat? what is the dlta t indoor coil? did you try to calculate the subcooling and superheat? what is the compressors amp draw? 100 deg coming in may not be too high if the space temp is high and the charge is low.... like I said you need more info to make a correct diag... it could be the vavles are leaking and or you have an unloader open or a hot gas bypass or a desuperheater problem. or other problem.
Luca1500 6 months ago
dead on, exactly how i was taught
demoney100 7 months ago
Thanks,I got a clear understanding on how to ohm a compressor
60darnell 7 months ago
Hey im suppose to meet with a counsler tomorrow about going to school for HVAC...i notice in craigslist the requirements that you need a clean driving record..Although i haven't gotten a ticket in over 10 years i still have this reckless driving in my record because it was misdermeanor...Is this gonna be a problem for me?
savator408 7 months ago
@savator408 That all depends on the employer. Just be honest with them.
DrZarkloff 7 months ago
@DrZarkloff k thanks....im starting the hvac program in 2 weeks...although i think the wreckless driving might be out of my driving record because it's been over 10 years...i looked it up and it said it stays in your record for 7 years so hopefully it's gone...thanks for the reply..
savator408 7 months ago
@savator408 I just finish school for HVAC/R this year of March 17 E.P.A 608 Certified Universal. It feels good to have those papers. Now I'm working,but they didn't ask me about my driving record. I guess every company is different. I have a speeding ticket on my record and they still hired me.
eastsideatlanta 7 months ago
@eastsideatlanta so your doing hvac work now? if so that's good for you...im starting next week and im already on craigslist looking around the states to see if they are hiring for HVAC jobs..and all the states in the US are hiring for HVAC work...i even checked out Atlanta and they have a few also...i live california but its a bit expensive to live out here...so i was looking outside of California i think Atlanta might be a perfect place or even Denver...
savator408 7 months ago
@savator408 Yea. Well I got hired for overseas work in HVAC, but it's a lot of jobs here in Atlanta for that I also be on craigslist.
eastsideatlanta 6 months ago
Great video!
Jamieinchains 9 months ago
@Jamieinchains Thanks.
DrZarkloff 9 months ago
I dont care if you've already turned off the power , ALWAYS CHECK
samec666 9 months ago
@samec666 Very true.
DrZarkloff 9 months ago
Dr. Z ,, u did not show us how to check the compressor mechanically ? Thanks
vrejian 9 months ago
Thx you Sir!
spiritlight9k 10 months ago
thank you Dr Z
tommy33004 11 months ago
This has been flagged as spam show
Hello Dr Z I have been watching your videos with great interest. I am currently in school learning Hvac. I need your help I was having a discussion about charging an AC system. I have instructors who say you have to use superheat all the time to determine the proper charge. I have other instructors who say if the ac is equipped with a TXV valve you charge by sub cool Who is right
My name is Tom Higgins
Email is tommy33004@yahoo.com
Could you please respond and maybe do a video explain things
tommy33004 11 months ago
Hello Dr Z I have been watching your videos with great interest. I am currently in school learning Hvac. I need your help I was having a discussion about charging an AC system. I have instructors who say you have to use superheat all the time to determine the proper charge. I have other instructors who say if the ac is equipped with a TXV valve you charge by sub cool Who is right
My name is Tom Higgins
Email is tommy33004@yahoo.com
Could you please respond and maybe do a video explain things
tommy33004 11 months ago
@tommy33004 You charge a system by superheat if the system has a fixed orifice and you charge by subcooling if the system has a TXV.
DrZarkloff 11 months ago
Hi dear Dr.Zarkloff
could you explain about flash gas and why its happen
and what is it ( LPA pumpe) and how its prevent of FLASH GAS PLEAS
farshadSuzuki 11 months ago
@farshadSuzuki Flash gas is usually caused by a low refrigerant charge.
DrZarkloff 8 months ago
.002 ohms? Did you have your meter on the 1K scale and are actually reading 2 ohms? Most normal windings are somewhere under 10 ohms aren't they?
Leaderoftheplanet 11 months ago
@Leaderoftheplanet I had my meter set to the ohms setting on the Fieldpiece HS36.
DrZarkloff 11 months ago
Is measuring a winding to ground also important?
ckjohnsonp 11 months ago
@ckjohnsonp Most definitely.
DrZarkloff 11 months ago
BTW great videos DrZarkloff!!
hvachessler 11 months ago
I have seen a number of compressors with a winding shorted to the case. which measureing from start or run to the case.
rick601a 1 year ago
@rick601a You should have no continuity to ground on any of the compressor terminals with your meter set to the highest ohm scale. I have seen compressors run with slight shorts to ground but they don't run long.
hvachessler 11 months ago
In school, I remember that a compressor can (unintentionally) run backwards. On a three-phrase all you do is switch any 2 terminals. How can you tell in the compressor is running backwards? I know it takes almost no time to ruin the compressor if running backwards. What do you do if a single phase compressor runs bakwards?
BGreenHVAC 1 year ago
@BGreenHVAC Scroll compressors will make a bad sound and the high and low pressures won't change if it's running backwards. It doesn't matter which direction a reciprocating compressor is turning.
DrZarkloff 1 year ago
If your ohm's jump real high when you are ohming that means you have a winding to winding short!
medahenderson1008 1 year ago
@medahenderson1008 No, if the resistance jumps high that is a winding about to fail as in about to open up or it could be a bad connection with your meter leads, or a bad internal protector. If the resistance is low that is a winding to winding short.
hvachessler 11 months ago
For single phrase compressor. There is no mark on compressor. How can you tell which one is run,common and start ?. How can you tell a new compressor which one is high side and low side ?.
Thanks
khonglap 1 year ago
@khonglap The terminals on a compressor is marked at the terminal block and the larger tubing is the suction side and the smaller tubing is the liquid side.
DrZarkloff 1 year ago
@DrZarkloff
hello sir i want to see the video of deasambling or semi sealed hermetic compressor pl
your previous videos to good
thanks
ALIHVACR 1 year ago
Can someone please help me my house has no heat having fan problems. Please watch my video that i uploaded and give me some pointers please. I would really appreciate it.
GPShaxor 1 year ago
to ground !?
willard30 1 year ago
Thank, this really helped my trouble shooting skills.
freemanronald 1 year ago
im glad u put these up here..thankx
DaGR8Twon 1 year ago
Dont get me wrong as I think your great and most of your vids are correct but you should always teach to turn off the power supply first and then test the terminals before you touch them, you should also have insulated screw drivers and plyers and you should use the ohms scale on your field piece meter and you should test each winding to earth.
Cheers
dnlp69 1 year ago
My bad I couldn't believe it was actually a thousanth of an ohm!! Bro in electrical sense this is neglible or useless. Why because even the soundness of the battery in your meter can affect its reading by a few fraction of an ohm. Not pressing the test leads as hard as the other can make you change the compressor for nothing!!
tangnatalaga 1 year ago
Bro I don't mean to be rude but if you put the two test leads together, you will get a very low reading like that. That means the winding have almost no resistance to DC current. Tightness of the test lead on the meter, how hard you press the lead on the terminal, how clean the terminals can actually make a difference of a even a few tenths of an ohm. You base the reading on a hundreth of an ohm!
tangnatalaga 1 year ago
Bro I don't mean to be rude but if you put the two test leads together, you will get a very low reading like that. That means the winding have almost no resistance to DC current. Tightness of the test lead on the meter, how hard you press the lead on the terminal, how clean the terminals can actually make a difference of a even a few tenths of an ohm. You are base the reading on a hundreth of an ohm!
tangnatalaga 1 year ago
Hi, your videos are great. They teach a ton. Any
how the question I have for you is where can I get EPA certified closed book exam. I live in Milwaukee Wisconsin.Thanks
rockiesrock56789 1 year ago
@rockiesrock56789 You should be able to go to any HVAC supply store in your area that is a certified proctor for the exam.
DrZarkloff 1 year ago
Help HVAC Town grow HVACTOWN. COM
HVACTalkTown 1 year ago
Hello Dr. Zarkoff...I have a problem with a compressor that electrically is good when i ohms it...but is falling mechanicallly because is tripping the braker and I know is the compressor becuase I unhooked the voltage to the compressor and the fan was working...my question is if the compressor fails electrically would it trip the braker or not?
catrachomg 1 year ago
@catrachomg Mechanical failure doesn't always mean that the breaker is going to trip. For example: if the motor shaft breaks, the compressor won't do any work and the motor will just turn without a load.
DrZarkloff 1 year ago
@catrachomg It depends, does it trip as soon as the unit calls then yes, if you can start the unit check the amps with a amp clamp then compaire to the name plate data. thare is two amp readings RLA running load amps. LRA locked rotor amps. if you read locked rotor amps the compressor is gone. When you did your ohms check did you check form each one to ground to see if the comprssor is shorted internelly?
hondaboy1988 1 year ago
I'm not writing this to hate on you in any way, but I just think it would be wise to announce in your video that this is intended for professionals. I went to two years of school and took a state license exam, so that I would know the proper technique and have the proper safety precautions in mine. The home or business owner does not need this information, or at least to take it lightly. Watching you do something and then thinking they know what your even talking about, should not be done.
Duttydutdut 1 year ago
Hello DrZarkoff your videos are very helpful and thank you very much for uploading them.
rokindjjay 1 year ago
@rokindjjay Thanks for watching.
DrZarkloff 1 year ago
@DrZarkloff You do know that on the fieldpiece and most other meters that continuity is not the same as resistance. You want to measure in the OHM setting, this is to ensure an accurate reading. Plus you didn't check these compressors to ground. I'm not trying to pick this to death but who is this video intended for? Amatuers or professionals?
Duttydutdut 1 year ago
Excelent, thanks for the Video Dr., now all I need is relay switch
fessorx22 1 year ago
WARNING!!
Never measure the resistance of compressor motor windings at the compressor terminals, especially if the compressor motor is suspected of being damage. Certain types of compressor motor electrical failures can damage the compressor terminals. Touching the damaged compressor terminals, especially if the compressor is under pressure, can release that pressure, causing injury or death. Always recover all the refigerant before testing at the terminals if you have no other choice.
gofixmechickenpotpie 1 year ago
hey there great video, you just helped me with my lab report! Shout out from Sarnia Ontario - chemical production and power engineering program
metalzombie1 1 year ago
@metalzombie1 Cool. Thanks for watching
DrZarkloff 1 year ago
HI. GOOD AND VERY INTRESTED VDO CLIP SIR
t9739 1 year ago
@t9739 Thanks for watching.
DrZarkloff 1 year ago
hi,you know you're my teacher?you are really good thanks for all,i will ask you a million questions but one at a time,its real that if i run my ac all day long its more cheap than stopping in 8 in the morning and then start up at 6 pm?i live in florida heat
carlitosgy6 1 year ago
@carlitosgy6 Thanks for watching my videos. I've always found that setting back the setpoint on the thermostat when you aren't at home saves electricity, hence saves money.
DrZarkloff 1 year ago
Excelent thanks.
isaacplazas 1 year ago
I agree IndieBraah, never do directly at the compressor if it blew out could kick your hand into a live circuit or hurt you.........
Nspect 1 year ago
@Nspect I was a HVAC tech for over 10yrs and still work on the side for myself as a tech. I always ohm out the compressor at the terminals. As he says this eliminates any false readings through the wiring. As for the terminal blowing knocking your hand into a live circuit you should NEVER have the power on when ohming a compressor at the terminals in the first place. You can also do a continuity check to see if the compressor is shorted to ground.
jesusnagstring 1 year ago
Thanks for this video mate it helped alot
DaVeHoLpRiDe 1 year ago
DrZarkloff I have a question. In the video you pull the compressor leads off of the terminals directly to ohm them out. I have been always told that you should never do this unless the charge is pulled out of the system because, the terminals can shoot out and blow your hand off while the system is under pressure. I'm only a 4 year tech from So.Cal. Just wondering if that is a myth or true what they say?
IndieBraah 1 year ago
@IndieBraah I've never had it happen to me. I like to ohm the compressor at the terminal block just in case there's a problem with any of the wires.
DrZarkloff 1 year ago
@IndieBraah You are correct. It's not a good practice to directly push on the terminals with the leads of your meter while the compressor has pressure in it. If you think about it, the terminals are held in place by a bake-o-lite (plastic) insulating material. Basically it's a plastic plug. If the seal around that plug is weakend, and the pressure of you pushing on it while testing for continuity, the terminal plug could blow out.
Harleydude2 1 year ago
@IndieBraah Part 2 to my response... There used to be a training video years ago put out by a compressor manufacturer that showed the terminals blowing out of a compressor. As you can read from below comments, there are people who claim to have experience and offer both points of view of how to check for terminals. I can tell you that I teach HVAC for the USAF and USN and we teach never to check directly on the terminal plug. Why tempt fate and end up a statistic? That's my motto...
Harleydude2 1 year ago
Comment removed
IndieBraah 1 year ago
on ohming compressor i noticed you have your meter set to continuity to to ohms does it matter
george6964 1 year ago
@george6964 The continuity setting is used to read ohms on the Fieldpiece HS33. The Fieldpiece HS36 has separate settings for each.
DrZarkloff 1 year ago
yes i thought i turned off the power two days ago on a three phase 460v packeg unit.and the next thang i no i was stuck to the unit and yelling at the top of my lungs..not fun thank god i have some waight on my bones cus i was on able to pull my hands off.. scared the shi_ out of me. so pleas all tecs and installers dont trust outher pepoles work or word check for voltege..thnx
baydestrian84 1 year ago
@baydestrian84 Yeowch! Amen to that.
DrZarkloff 1 year ago
@baydestrian84 A shock from a 440v unit is no freekin joke. Could cause death or at the least serious burns. I use one of those non contact probes just to be sure the power is off. I almost shocked myself on a attic air handler the other day on a multi unit building. I shut off the wrong breaker, good thing I checked with the probe before putting my hands in there.
douglas787 1 year ago
@baydestrian84
Assuming voltage is not present is not a good idea. Testing and double checking could be a life saver for you or anyone that gets involved with electrical projects. Getting hit with 277 VAC usually ends with you running in circles calling out the voltage like a voice activated multi-meter. And 460 VAC will shut you down quickly. Take care baydestrian84 and DrZarkloff is a Professional that would never lead you to believe assuming is a good idea.....Sea Breeze
Bearfly 1 year ago
Look at 1:47 in the video. You have your HS33 Fieldpiece meter set on continuity. You have a tone, a light, and the knob is pointing to this setting. I have the same meter. What should you be reading on ohms on a scroll compressor let's say 4 tons?
robertcyders 1 year ago
@robertcyders I'm not sure. You could test the scroll compressor in the same manner as long as it's single phase. Three phase compressor should ohm the same between each winding.
DrZarkloff 1 year ago
Sir,
I have installed Petra chiller its expansion valve got stuck 05 to 06 times in two years there is installed Danfoss SS body valve, Please reply what cause of getting stuck the expansion valve.
Regards
M. Ismail
2170509 1 year ago
@2170509 The valve could have got stuck if a piece of trash clogged the orifice. Sometimes, an oil flood back can simulate a stuck valve. By the way, I prefer Sporlan expansion valves. Enough said.
DrZarkloff 1 year ago
Sir,
I have installed 1/2 hp compressor Danfoss 134 a in fridge its getting to heated and compressor return came means suction line temp. came at above 20 psi I read in book at 80 Fahrenheit, suction allowable temp 30 to 20 Psi so 20 psi pressure of suction line is it suitable? Please Reply Dr. Zarkloff
2170509 1 year ago
@2170509 You should just weigh in the refrigerant charge. Don't be too concerned with the suction pressure unless it's too low and the line is icing up.
DrZarkloff 1 year ago
were those compressors under pressure because my teacher say's that checking ohms at the terminals on the compressor might blow out on you. What can you tell me about that
deyenak1 1 year ago
@deyenak1 I've never known that to happen. I have had a compressor blow out after energising it with power.
DrZarkloff 1 year ago
@deyenak1 that is if you are doing a hipot test using a megohmmeter (resistance to ground using a high voltage dc source).
ppwalk05 1 year ago
me again house is 1700sq ft 4 ton unit
juanater2000 1 year ago
me agail house is 1700sq ft 4ton carrier unit
juanater2000 1 year ago
Hi i was adjusting my swing setting and wondering my unit runs about 14min on and 14 min off . 100f out side. i know theres alot more to factor in but what do you think about that? would it be more efficent to run on say 10 min ? how long should it run at that outside temp aproxx? thanks
juanater2000 1 year ago
@juanater2000 It should be running until the indoor temperature reaches the thermostat set point. Your system could be shutting off on high head pressure. Try cleaning the condensing coil.
DrZarkloff 1 year ago
Resistance measurement cannot determine a shorted coil. I mean any type of coil specially the ones in a compressor. Although it can determine an open winding which rarely happens. A ring test can be performed using an oscilloscope and a signal. Even then it is not 100% reliable. I don't even know why some technical books have sections in measuring Resistance in coils. It is useless and a waste of time and may lead to confusion.
tangnatalaga 1 year ago
Hi, Please make me know, can we charge the gas in the system with gas? when we know TR of the system I am talking about gas quantity in weight I know when the system RFT increase gas quantity also increase but is there available thumb rule when capacity so and so then quantity so and so.
Regards
2170509 1 year ago
An open in the winding will help you with DC resistance measurement, but if there was a short you would not be able to measure it with a regular ohmeter.
tangnatalaga 1 year ago
When you use an ohmmeter you are only measuring the DC resistance of the compressor coil which are very low. Remember the winding act upon the 60HZ cycle of the house current!! You have to measure IMPEDANCE which is not the same as resistance!! You have to know the size of the wire the number of turns, the size of the loop and what the core is made of then the frequency of the current which is 60 HZ. Measuring DC resistance on compressors are useless. Now coils that has many turns its ok.
tangnatalaga 1 year ago
You are only measuring the DC resistance of the coil. I would use what you call a ring test. It is the same way we determine a bad flyback transformer in a television. Note that coils characteristic are measure in IMPEDANCE not in RESISTANCE which is what your meter is reading. Coils IMPEDE current they do not resist them. I think AC technician do not understand enough about electricity. Even the ones in the field for a long time.
tangnatalaga 1 year ago
This has been flagged as spam show
It's working but condition is that when compressor cools it starts smoothly but when compressor have been runing for long time electricity goes out when electricity comes back after dealy the time it does statr because it gets hot. after delaying 05 to 10 minutes it starts.
2170509 1 year ago
It's working but condition is that when compressor cools it starts smoothly but when compressor have been runing for long time electricity goes out when electricity comes back after dealy the time it does statr because it gets hot. after delaying 05 to 10 minutes it starts.
2170509 1 year ago
@2170509 Not to step on the doc, but might I suggest you have a restriction in your line. Possibly at your TXV. It would make sense if your compressor were not getting enough refrigerant intermittently. It would shut down, cool off then restart. If I were you I would try and blow out the lines with nitrogen.
thetenia 1 year ago
@2170509 It sounds like the compressor is shutting down on a high head pressure. Have you cleaned the condensing coil?
DrZarkloff 1 year ago
Sir, I have installed the compressor which gets so I checked the compressor so it's C-S = 0.024 Ohms , C-R = 0.005 & S-R = 0.029
I found that compressor is electrically O.K as per your teaching but make me know that C-S ohms is too high as compare to C-R. Is this reading is sufficient?
Regards
2170509 1 year ago
@2170509 Mathematically, the windings checked out good. Does it run okay?
DrZarkloff 1 year ago
Sir, When the refrigerant piping RFT increase so should the OD increase? or if the OD is increased on which side does the OD increase.
Regards
M. Ismail
2170509 1 year ago
Sir, I have installed Mitsubishi Packaged type split unit Model # FDC81BA & FDC101BA its compressor have changed 02 times converted Copland so please send me the quotation of Mitsubishi Compressor.
And make me know I got the new compressor installed after installation and commissioning of the compressor it was out of order mechanically than we got it repaired for few days it operates in sufficient condition but it has got out of order mechanically again. So what is the problem it h
Regards
2170509 1 year ago
@2170509 You might want to call the tech support at Mitsubishi.
DrZarkloff 1 year ago
Hi, Ilike your vids, I am actually wanting your input on my ac unit, my evapoators are freezing up, and I hooked up the gauges and the readings are the same with the compressor off and running. checked the ohms and read good. but is the compressor bad mechanically? even though the evap's freeze?
extreme383 1 year ago
@extreme383 You really need to let the evaporator to thaw before checking the gas pressures. You'll get inaccurate readings when the coil is iced up.
DrZarkloff 1 year ago
@DrZarkloff Hi, oh yes I did, it was a few days after they thawed out.
extreme383 1 year ago
@extreme383 First, if the evaporator is icing up then you're going to get different readings when the system is on than when it off. It just doesn't make sense to me why you'd get those readings.
DrZarkloff 1 year ago
@DrZarkloff hmm, well the pressure did go up slightly but not much. could the valves be bad in compressor?
extreme383 1 year ago
@extreme383 I can't say for sure. It just doesn't seem logical that the evaporator ices up and your pressures are the same on and off.
DrZarkloff 1 year ago
Thanks DrZarkloff: May God give you the regard
You have tough me how to check compressor electrically but How should I check the compressor mechanically both types Hermetic Sealed and Semi Sealed compressors.
Thanks
M. Ismail
2170509 1 year ago
@plaebslayer If you have anything other than OL (open line) between the windings and the compressor housing and suction line, which would be ground, you have a bad compressor.
DrZarkloff 1 year ago
@plaebslayer You either have the meter set wrong or you have a faulty compressor.
DrZarkloff 1 year ago
Hi, I am really impressed to you. Please make me know that how to check three phase compress electrically & mechanically?
Thanks
M. Ismail
2170509 1 year ago
@2170509 I'll make a video on this. For now, just so you know, L1 and L2 should ohm the same as L1 and L3 as well as L2 and L3.
DrZarkloff 1 year ago
Hi, You really impressed me I have saved many clips, will you please make me know how to check three phase compressor electrically and mechanically.
Thanks
Your fan
M. Ismail
2170509 1 year ago
when you were using the ohmmeter do you have it on the highest scale because .002 is almost a short.
artsugaoka1 1 year ago
@artsugaoka1 The HS 33 has only one selection to read ohms and continuity. Those where good numbers.
DrZarkloff 1 year ago
Great stuff!
ehmr34gtr 1 year ago
You didnt check to see if it was grounde on the first one.
HVACTECH4105 1 year ago
@HVACTECH4105 Sorry about that. Yes, you really should check the windings to ground.
DrZarkloff 1 year ago
@HVACTECH4105 Yep most times when a compressor burns out it shorts to ground. And if the terminal block blows clean out of the compressor and their is black oil all over the interior cabinet it will be really obvious lol! ARRRGG I hate it when that happens.
crazyredlion4500 1 year ago
OK. man yuo are #1 ,I,m so liket to wach you ,the video help me up .tanks from
TheDeda35 1 year ago
@TheDeda35 Thanks for watching.
DrZarkloff 1 year ago
i've a condense leaking between copper fin and lumnium , where is manufacture made joint solder, any way can we fix it ,by reg. copper solder? thanyou for any advice mr. drzarkloff
tranwatson 1 year ago
@tranwatson You might want to cut the tubing at the hole and use something like the HVAC Pro glue.
DrZarkloff 1 year ago
i have my second interview on tuesday as a trainee HVAC eng, your vids are great im taking notes and trying to remember as much as posible if you have any tips for me for my interview that would great.
sniperusg50 1 year ago
@sniperusg50 I wish you all the best.
DrZarkloff 1 year ago
ha, i never really thought about adding em like that, lol... but anywho??? did you every ohm it to ground??? or check LRA on that compressor
death2opposeme 1 year ago
i dont know why but i like your vidz, even though i know all this shit. its still good review i reckon. better than other vidz i have seen elsewhere.
death2opposeme 1 year ago
@death2opposeme Thanks for watching. I probably need to make another video showing how to ohm to ground.
DrZarkloff 1 year ago
This guy reminds me of Jeff Daniels.
jasonrtilden 2 years ago