Reason why 120 to ground was showing on both sides of the contactor is because you have a closed circuit through the contactor coil...once you pulled the terminals off you interrupted the flow across the coil. Hope this helps and keep up the great content.
I always appreciate your videos! You made this one a little more complicated then it needed to be. Me personally I always do all my interior box checks before heading to the roof. That includes taking the cover off the thermo which would have led you to the issue right away and this job would have been done very quickly. I’ve found it very important to approach walk in calls the same way every time and have a procedural way of doing it so I don’t miss easy things like this. Also I would never say a load is working/not working by testing pins to ground, 120v on both sides to ground is not the same as 208v across the coil. There are several reasons to why you would have those voltages but testing across for 208v is truly the only way of know if it should be energized or not. I think you’d benefit by approaching these calls the same way every time rather then changing how you do things based on the condition! Do it in a procedural way for a year and you will not get stumped on calls like this and you will have a vastly better understanding! I’ve been training a few techs lately and I’m really just trying to help! Keep up the good work JMT!
As my journeyman always told me the meter will always tell you the path! My Multi Meter is my best friend, no matter who tells you what’s not working or disconnected ( upside down switch?) I always meter every thing myself before I start. P.S the meter can save your life!
Think of the coil as just a length of wire (which it is). When only one side is connected to AC, then it will act as a wire, so you will always see a similar voltage at both ends of the coil with reference to ground, but no voltage across it because no current is flowing. When there is power applied across both terminals, the coil is energised, current will flow and it will drop voltage across it, so you will see a voltage between the terminals.
Jumper man keep on jumping ! Don't feel bad electrical troubleshooting has humbled us all at some point lol. These types of struggles are the types that will elevate you to electrical master in no time. Bottom line if a component is tagged for 208,120,24 etc and you don't get it from post to post then the component is not bad and you should keep on working backwards from there.
You had 120 on 1 side of the contactor and power was flowing threw the coil giving you the same 120 out. Testing ac voltage should be done leg to leg. Not leg to ground like DC. But none the less you figure it out and fixed it good job bro.
Great video. You were a little confused with 120v to ground on each side of the contactor coil but nothing across. That's typical 208v control meaning you lost a leg of 208 which you found at the burned up wire at the tstat. Still wonder why you didn't check 208v at the time clock to power it up when your green light was out? Hopefully your next call there isn't an iced up coil due to time clock motor not powered up. lol. Love the liquor check at the end!!
Great video. I noticed their was no green light on the clock tho. Should have checked 1 to N and 4 to N. Then put in defrost to make sure it cuts off the tstat. Then check 3 to N. Always check wires when no romex is used. The definitely rub out.
Interesting video! Thanks for posting. That 'isolator' switch may be upside down for the US, but here in United Kingdom, Europe, (I'm British by the way) that's the normal way for switches.
As mentioned.... when troubleshooting 208v controls circuits.... you can't measure to ground, You must assign an L1 and L2. L2 is the "neutral" of the circuit.
Hello, great educational videos. I would like to ask if you could make a video about your parts, what parts you constantly carry in your truck, universal or commonly encountered ones. For refrigeration equipment. I do residential HVAC and am also adding refrigerators to expand my business.
the 28 volts was coming through the coil from the live side of the contactor and then dropping to ground as the difference between the phase and earth (ground in the US). If you think the contactor control coil has failed (Which does happen with coils energized for hours on end), disconnect the coil and do a resistance test across the coil. These pesky faults can have you chasing your tail for ages if you are focused on whats wrong an see something weird... I always do the supply test first, then the contactor tests after checking the fuses are good and then the switches and the starting caps.... if they all look good, then look at things like compressor winding resistances.... Some of these systems start out well designed, but the differing skilled contractors on a quick turn around can turn the unit into a heath robinson setup so quickly... Kudo's for staying focused on getting the control circuit ironed out dude....bravo
Now you did a good job troubleshooting. I was thinking coil too , But when you pull that wire off the coil and all of a sudden, you had twenty eight Volts I thought the same thing you did , huh? Lol!
Good job man. A little bit of a confusing call. But you got it right. Its crazy how different HVAC is in NY due to limited space. I'm in Wyoming and almost never see water cooled condensor on anything most chillers are air cooled. Actually a decent amount of vrf stuff out here it's getting out into old commercial buildings because install is less invasive. Thanks a bunch for taking the time to make these service call vlogs.
Word of advise. Do it the european way, single phase or triple phase. Not those 208 thing. Coils using LNE (230V), motors using either 230V LNE or 400V 3 phase (usually without N). Electricity in Europe (DK), is much easier.
Nice find! Was sitting here saying it's the contactor. Lol appreciate your videos. New to the trade. Normally work on the hot side. Follow up on the indicator light on the defrost timer? I thought walk ins don't do defrost. Help
Your AC voltmeter measures voltage drop, it measures 208v across an energized coil because there is a 208v drop across the load. 120v on one side of a 208v coil will still conduct across the coil but will show 0v drop across the coil because there is no load.
Missing a leg from the defrost clock buddy Seems your other leg of the coil is the #4 from the clock, if the clock is bad or has bad contacts which your clock has no lights you’ll never have your other leg to the coil to contactor unless stuck closed which in this case it might be it, hope it helps You check to ground to verify but not to diagnose as it’ll always throw you off
@@skanteroar 😂 it’s cool man we don’t all know it to be the main power source of operation on a unit but then again we all get tunnel vision sometimes and that could mess with us hard, just glad he found the short in the wire but that clock not lighting up indeed shows to be bad
Thank you!! It was quick to come down to about 45 but from there it took a while to reach about 38 degrees. I'd say about 1 hour. Thanks for watching 🔧⚡️
@@JumpermanTechdefinitely dangerous to have high voltage on stat wire. Easy fix is to install a transformer and 24v contactor to power the control circuit. Btw the small metal switch is a pump down switch.
Check defrost timer for power if there is power present clock bad that’s why u had no green light or red when u turn the clock. if u follow the red wire coming from defrost clock its ur other half line for contactor. U just bypass the defrost clock and called it a day
Measure neutral to ground then live 1 and live 2 to ground. Using 24V thermostat wire for a 208v control was plain dangerous 😳. Thermostat wire insulation is only good up to 120v max before it fails, and only legally meant for low voltage service. A shorted solenoid coil could have easily started a fire because the wire would have burned up before a fuse would have blown. Scary 💩
No grommets on anything! Gentlemen, when you’re running wires through anything!,, put grommets on every entrance any junction box or any thermostat.. installation failure!
At least it wasn't full of rotting food they were still serving to customers.... been there. Installers put stuff in like it will never have to be serviced. Been there too.
That defrost clock not having any sort of light is der strange. Led's burnt out it seems. Probably a good idea to get rid of that thing as well. Thanks for watching & commenting 🔧⚡️
I suggest you go back to basics as your electrical fault finding is haphazard and poor. You need to learn to test correctly follow the circuit step by step and by process, just grabbing wires and testing to earth does little or no good unless you charge by the hour... Test across the terminals not to earth as power was going through the contactor coil to the other side but coming to the other side. This was very obvious early on. if you went across the coil you'd see immediately one leg was missing. Blaming the contactor early on was another obvious "fault finding by assumption rather than by diagnosis" Sure you got there but you went round in circles and got lucky. Thanks for sharing, and good luck going forward
Reason why 120 to ground was showing on both sides of the contactor is because you have a closed circuit through the contactor coil...once you pulled the terminals off you interrupted the flow across the coil. Hope this helps and keep up the great content.
I always appreciate your videos! You made this one a little more complicated then it needed to be. Me personally I always do all my interior box checks before heading to the roof. That includes taking the cover off the thermo which would have led you to the issue right away and this job would have been done very quickly. I’ve found it very important to approach walk in calls the same way every time and have a procedural way of doing it so I don’t miss easy things like this. Also I would never say a load is working/not working by testing pins to ground, 120v on both sides to ground is not the same as 208v across the coil. There are several reasons to why you would have those voltages but testing across for 208v is truly the only way of know if it should be energized or not. I think you’d benefit by approaching these calls the same way every time rather then changing how you do things based on the condition! Do it in a procedural way for a year and you will not get stumped on calls like this and you will have a vastly better understanding! I’ve been training a few techs lately and I’m really just trying to help! Keep up the good work JMT!
This comment helps me.. im a rookie tech, thank you!!
That certainly makes sense.
Dude don’t ever check voltage to ground as a diagnostic test. It’ll mess you up every time. Always reference the other leg of power.
As my journeyman always told me the meter will always tell you the path! My Multi Meter is my best friend, no matter who tells you what’s not working or disconnected ( upside down switch?) I always meter every thing myself before I start. P.S the meter can save your life!
Checking voltages to ground when troubleshooting can often get you confused. Great video.
Great find, I’m not real crazy about them using t-stat wire for line voltage. Always great job thanks
Thank you! That t stat wire should definitely be replaced. Appreciate you watching & commenting 🔧⚡️
Your electrical troubleshooting skills were fun to see. This is journeyman level electrical control systems troubleshooting at its best
Aw man! They used thermostat wire for line voltage!! 😮
Your doing a great job by the way! Great video!
Wiring is probably burnt from higher amp draw. 18 gauge wire not to be used for line voltage
Definitely should not be used for line voltage. That should be replaced 💯
Think of the coil as just a length of wire (which it is). When only one side is connected to AC, then it will act as a wire, so you will always see a similar voltage at both ends of the coil with reference to ground, but no voltage across it because no current is flowing.
When there is power applied across both terminals, the coil is energised, current will flow and it will drop voltage across it, so you will see a voltage between the terminals.
Jumper man keep on jumping ! Don't feel bad electrical troubleshooting has humbled us all at some point lol. These types of struggles are the types that will elevate you to electrical master in no time. Bottom line if a component is tagged for 208,120,24 etc and you don't get it from post to post then the component is not bad and you should keep on working backwards from there.
You had 120 on 1 side of the contactor and power was flowing threw the coil giving you the same 120 out. Testing ac voltage should be done leg to leg. Not leg to ground like DC. But none the less you figure it out and fixed it good job bro.
I thought it was a bad contactor too, what a strange call man. Glad you figured it out!
Great video. You were a little confused with 120v to ground on each side of the contactor coil but nothing across. That's typical 208v control meaning you lost a leg of 208 which you found at the burned up wire at the tstat. Still wonder why you didn't check 208v at the time clock to power it up when your green light was out? Hopefully your next call there isn't an iced up coil due to time clock motor not powered up. lol. Love the liquor check at the end!!
Holly shit. There using low voltage thermostat wires for line voltage.
That was definitely an interesting find 😂
WE LOVE YOU GUY, YOU ARE NUMBER ONE....
Great video. I noticed their was no green light on the clock tho. Should have checked 1 to N and 4 to N. Then put in defrost to make sure it cuts off the tstat. Then check 3 to N. Always check wires when no romex is used. The definitely rub out.
N to 1 is the line voltage that powers your defrost clock always start there when no lights are ON at the clock.
Great digging.
Good job Jumper.
Thank you John!! 🔧⚡️
Interesting video! Thanks for posting. That 'isolator' switch may be upside down for the US, but here in United Kingdom, Europe, (I'm British by the way) that's the normal way for switches.
Thank you! That's interesting how it's the opposite where you live. Thanks for watching & stay tuned for new videos every week🔧⚡️
Good job sir
As mentioned.... when troubleshooting 208v controls circuits.... you can't measure to ground, You must assign an L1 and L2. L2 is the "neutral" of the circuit.
Hello, great educational videos. I would like to ask if you could make a video about your parts, what parts you constantly carry in your truck, universal or commonly encountered ones. For refrigeration equipment. I do residential HVAC and am also adding refrigerators to expand my business.
Very good
Most excellent 👍👍👍💯
Thank you very much!! Stay tuned for new videos every week🔧⚡️
Wow , that was great, you caught it , I thought something is about to blow up 😂
Thank you! Haha thankfully nothing blew up & that wire didn't shock me while I took off the cover. Thanks for watching!
@@JumpermanTech ya good eyes.
I enjoyed the video.
Take care
@@mansourramzey7711 Thank you! You also take care and enjoy your weekend ⚡️
the 28 volts was coming through the coil from the live side of the contactor and then dropping to ground as the difference between the phase and earth (ground in the US). If you think the contactor control coil has failed (Which does happen with coils energized for hours on end), disconnect the coil and do a resistance test across the coil. These pesky faults can have you chasing your tail for ages if you are focused on whats wrong an see something weird... I always do the supply test first, then the contactor tests after checking the fuses are good and then the switches and the starting caps.... if they all look good, then look at things like compressor winding resistances.... Some of these systems start out well designed, but the differing skilled contractors on a quick turn around can turn the unit into a heath robinson setup so quickly... Kudo's for staying focused on getting the control circuit ironed out dude....bravo
Now you did a good job troubleshooting. I was thinking coil too , But when you pull that wire off the coil and all of a sudden, you had twenty eight Volts I thought the same thing you did , huh? Lol!
Good job man. A little bit of a confusing call. But you got it right. Its crazy how different HVAC is in NY due to limited space. I'm in Wyoming and almost never see water cooled condensor on anything most chillers are air cooled. Actually a decent amount of vrf stuff out here it's getting out into old commercial buildings because install is less invasive. Thanks a bunch for taking the time to make these service call vlogs.
this isn't HVAC, it's refrigeration
I had a similar situation to this a while ago, it was for a crematorium, the bodies were beginning to get warm!!!
Nice find with that broken wire.
Word of advise. Do it the european way, single phase or triple phase. Not those 208 thing.
Coils using LNE (230V), motors using either 230V LNE or 400V 3 phase (usually without N). Electricity in Europe (DK), is much easier.
👍💪🇺🇸❄️ nice vid. Any thoughts about why clock wasn’t lit up ?
Nice find! Was sitting here saying it's the contactor. Lol appreciate your videos. New to the trade. Normally work on the hot side. Follow up on the indicator light on the defrost timer? I thought walk ins don't do defrost. Help
Your AC voltmeter measures voltage drop, it measures 208v across an energized coil because there is a 208v drop across the load. 120v on one side of a 208v coil will still conduct across the coil but will show 0v drop across the coil because there is no load.
Missing a leg from the defrost clock buddy
Seems your other leg of the coil is the #4 from the clock, if the clock is bad or has bad contacts which your clock has no lights you’ll never have your other leg to the coil to contactor unless stuck closed which in this case it might be it, hope it helps
You check to ground to verify but not to diagnose as it’ll always throw you off
@@jruizsr yes sir
Have made a wiring diagram board to train my brother that just joined the trade not too long ago
I was screaming by minute 5 to check power at the clock. I thought he was trolling by ignoring the clock.
@@skanteroar 😂 it’s cool man we don’t all know it to be the main power source of operation on a unit but then again we all get tunnel vision sometimes and that could mess with us hard, just glad he found the short in the wire but that clock not lighting up indeed shows to be bad
Great troubleshooting my man! How long doest it take for termostat to reach 35 !?
Thank you!! It was quick to come down to about 45 but from there it took a while to reach about 38 degrees. I'd say about 1 hour. Thanks for watching 🔧⚡️
That paragon clock did you dirty
Like I said. The low voltage wire can not handle the amperage from the line voltage running then it. The wire is only good for low voltages
Facts. It should definitely be replaced. So many shortcuts have been taken in this location
@@JumpermanTechdefinitely dangerous to have high voltage on stat wire. Easy fix is to install a transformer and 24v contactor to power the control circuit.
Btw the small metal switch is a pump down switch.
Check defrost timer for power if there is power present clock bad that’s why u had no green light or red when u turn the clock. if u follow the red wire coming from defrost clock its ur other half line for contactor. U just bypass the defrost clock and called it a day
Measure neutral to ground then live 1 and live 2 to ground. Using 24V thermostat wire for a 208v control was plain dangerous 😳. Thermostat wire insulation is only good up to 120v max before it fails, and only legally meant for low voltage service. A shorted solenoid coil could have easily started a fire because the wire would have burned up before a fuse would have blown. Scary 💩
Why would you read 0 volts on the thermostat if both wires get 120
This thing on it is like this counter low pressure cut out
yo measured 0 Volts across the contactor. That means there is no current getting to the contactor.
No grommets on anything! Gentlemen, when you’re running wires through anything!,, put grommets on every entrance any junction box or any thermostat.. installation failure!
At least it wasn't full of rotting food they were still serving to customers.... been there. Installers put stuff in like it will never have to be serviced. Been there too.
THERMISTAT WIRE FOR LINE VOLTAGE?!!!! Yikes, THAT INSULATION ISNT MEANT FOR THAT VOLTAGE.
Start at the defrost clock. Typical issue
That defrost clock not having any sort of light is der strange. Led's burnt out it seems. Probably a good idea to get rid of that thing as well. Thanks for watching & commenting 🔧⚡️
You should not even be repairing this for liability
I hear that!! Definitely some shady work has been done here 👀
Get rid of that Grassland defrost clock
😻💚💜💚
💜🔧⚡️
That is what separates the professional from the amateur
Yes sir! Thank you! Glad this one was repaired. It was a tricky one. Stay tuned for new videos every week🔧⚡️
I suggest you go back to basics as your electrical fault finding is haphazard and poor. You need to learn to test correctly follow the circuit step by step and by process, just grabbing wires and testing to earth does little or no good unless you charge by the hour...
Test across the terminals not to earth as power was going through the contactor coil to the other side but coming to the other side. This was very obvious early on. if you went across the coil you'd see immediately one leg was missing. Blaming the contactor early on was another obvious "fault finding by assumption rather than by diagnosis"
Sure you got there but you went round in circles and got lucky.
Thanks for sharing, and good luck going forward
Brain twister 😂
It seriously was! Had me stumped for a bit but I figured it out in the end😂 Thanks for watching! 🔧⚡️
Your videos are awesome keep them coming. 👏
Please do not check 208 to ground. You will not be able to troubleshoot that way. Honestly should not ever troubleshoot to ground with any voltage.
👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍
great walkthrough of the walk in ⭐️❄️🧊🥶
Haha thank you! Stay tuned for new videos every week🔧⚡️
even a blind squirrel finds an acorn once in awhile
That’s truly amazing trouble shooting 🫡