carriers are bad for a weak capacitor causing 1 fan to run backwards and then they act as an intake outtake fan and lock both out on high pressure. Sometimes it takes a gust of wind to start 1 of them backwards then by the time you check it the thing looks fine.
I love the fact that you are a younger dude doing old school troubleshooting tactics. It's quite refreshing to see reason and logic applied to fixing stuff. As a Canadian IT person trying my best to so the same, it's very refreshing to find others on the same track.
It’s always a disappointment and frustrating to see the wrong people hired into a position. Parts swappers , no troubleshooting ability.. wreck-nicians
Extremely thankful for your channel, my father makes a real good point when he says that my generation has a lot of tools that his did not, UA-cam being one of them !
I will discuss this on my Livestream this evening 5/1/23 @ 5PM (pacific) on my UA-cam channel HVACR Videos come over and check it out ua-cam.com/users/live6F1EzlQ4ZE8
@HVACRVIDEOS i know im late on this video. but ive found restricted filter dryer causing high head pressure and low subcoolong on these unit's, but both were locked out so maybe a fan, and i also check the temperature on the condenser fans with a temp gun. im in arizona so i have seen fan stop right in front of me and check the temp it was at 195⁰. its a habit of mine to check fan temps during PM'S. i know you're thorough, and i try to be thorough as well. question, how long have you been in the trade? p.s. i have a bit of ADHD . just mentioned that in case you notice my comment is all over the place. thank you for your videos. i watch them and try troubleshooting along with you and see if i can come up with a similar diagnosis. ill pause after you provide more info and see if my thought process is in the right direction . im 1 year in, and im learning every day in the video and in your videos. take care and stay safe out there!
Where is the dirt leg for the fuel line ? Be sure to check Condenser Fan Bearings. I used to check heat exchanger for holes. Could be time for a new unit.
That in any type of intermittent problems that can and will occur. Or that it takes a very specific sequence of several different events to get a problem to occur!
In situations where there is lockouts but no definitive code to tell you why it locked out. I will always do the full visual of the belt filters etc. but will always run the unit in its current condition to see what my readings are with the dirty filters or whatever may look out of sorts. Can sometimes help take away some of the uncertainties.
Chris looks to me like you nailed the issue that was a good bit of dirt that came out of the condenser coil, that combined with nasty filters and a good hot day 85+ could have kicked it out on high head. You have to think about the difference an 85+ vs a 70 degree day makes. That or with the dirty filters and a cold morning could have frozen it out.
Great video! It always drives me nuts when I am not 100% sure of what causes a problem. Glad I am not the only one that talks to themselves when troubleshooting.
I do factory service on fiber optic equipment for the broadcasting industry. The first thing I do after a visual inspection for obvious damage is to clean the fiber ports. After I've done that, 90% of units go though the test procedure with flying colors. I won't contaminate my lab tools with cheeto dust or bong resin or boogers, or whatever else field techs manage to smear onto their fiber optic assemblies.
Enjoy the topic. As a thought consider NU22, it is a close match to R 22, but by no means is equivalent, BUT much cheaper. If the unit was even in good condition, I too would go r-22, but take a look at the TP chart as a comparison. As temps at outdoor ambient gets higher the similarities fade... In addition the only think that comes to mind for the CLO fault MAY be a corroded connection or something like that, but since I also doubt it, I still have to mention it. SHit happens when you are not there and like the person below me said, "It never happens while you are there. The CLO are also notorious for corrosion. My .02 MPT...
I’m always glad to see a video on one of these, since I got into commercial over 3 months ago it seems like 90% the equipment I come across are these Carrier Weathermaster/maker/takers. Though lately I’ve had a run of Lennox RTU’s.
I had one unit with lock out board.occasionaly was giving me same lock out symptoms with 407c. Finaly I by passed that board and never had lockout issue again.
I once had a low pressure cut off keep cutting out so I bypassed it, never had a low pressure cut out on that unit again 🤣. I'm just messing with you, this thought just popped into my head so I had to lol. Btw if I would be in your shoes I would probably do the same.
So, If you change the refrigerant you kind of, have to re - engineer the unit!! That takes a bit!! It's a lot of fun but it can be a pain! All in all, well done!!
Once you ran it towards the end of video and building load came down to normal, I agree with you that circuit one looks like restriction in liquid line/or orifice. The second circuit though may be normal. Really helpful if there's a manufactures charging chart for the fixed orifice systems, if not I use a universal total superheat chart for fixed orifices. Indoor wetbulb/ outdoor drybulb gives you you're target superheat. when load comes down to normal in the building its not uncommon to see low evap superheat even as low as 2 like you had, without a chart to work off of its hard to tell if you're overcharged or if you need to dive in deeper. I don't work on hardly any fixed metering devices these days, pretty rare where I work which is why the charts are a life/system savor
Wax clogs in the metering lines .. 407c and R22 both hate alkyl and mineral oils in high heat environments. So im willing to bet that you have some wax junk in the metering device that really only shows up when the machine is loaded down in the heat. ALSO those glassfloss filters are possibly overkill for someone who doesnt keep regular maintenance .
You are lucky. Where I liveR22 is banned since 2015. My heat pump is using R22. If there is an issue with refrigerant circuit, it must be replaced. As long as it is working, it may stay :)
Hello from New Zealand. my first thinking is that blocked filters give you a colder evap coil due to lower air flow therefore lower heat absorbsion, this then reduces suction pressure due to reduced superheat and therefore lower head pressure. I would lean toward anti freeze stat lockout before high head pressures. clean filters and better airflow will help resolve that possibility. How many sensors in the fieldpiece kit? Love you videos! Our R410a is slowly being replaced by R32. large VRV still R410. single splits are generally R32.
For stage 2 you said it may be restricted but your super heat was 3-4 f. Wouldn’t a restricted fixed office tube cause high superheat? Thank you for your videos! I watch everyone!
It's funny this video came out because I've had 2 carrier systems do the exact same thing. One was a new install. Compressor was off on thermal. Upon reset there was no obvious sign why. Amp draw was good, pressures, tightened all connections, good temperature split etc... Still not sure what happened to this day.
Your clue on this one is the control wiring. The freezer Stat cuts off both compressors. Since it's the only safety that kills both, that's the issue. Can't prove it with gauges, but I'll be dollars to doughnuts that the coil froze up, triggered the freeze stat, and Bob's your uncle.
First stage is a wild card because of the 407C so the numbers are goung to be slightly off. Second stage with a sh of 2 doesnt really tell me there is a restriction in the fixed orifice. These units are notorious for restriction in fixed orifice but it's usually accompanied by slight or heavy frost at the orifices. Bottom line is the C coils are junk and the entire unit should be replaced. Great video!
it should be lower current with cover on, because it makes more resistance and lower total air flow, which takes the load off the blades and motor, which in turn increases rpm somewhat. the current will nearly always go down, unless it's some ECM cruft or something that adjusts speed to keep CFM the same.🤓
@@throttlebottle5906 That would be correct if we were talking about a centrifugal blower like you’d see in the evaporator section. With an axial fan it’s the opposite. Applying more static/resistance to the axial fan increases the load on the motor increasing the motor’s amperage. I’m also assuming that were talking about non ecm or the typical psc motor.
Nice video,i am wondering if when the stage one compressor was replaced with 404R they didn’t purge while brazing and drier currently have a restriction
The way you started the video; *don’t shut the AC power off* ; thought maybe this Carrier system had alarm / error code memory, (circuit board module). (Which would be a unique Carrier system for the year you indicated). 😳
Chris, have you thought if a high-wind incident, on this unit, caused the fans to spin backward causing the lock-out from high-head pressures? I had a few problems with Sportsmen Outdoor Store and I had the same type of issues. For the life of me, everything checked out, I came back 3 times in one week, and on the last visit I was on the roof taking a break just going through everything in my head, and just then a 60mph gust knocked me off my feet, I swear I was in a tornado and could not stand back up for about 30 minutes until everything got back to normal and herd A/C units dropping out like flys, all on high head pressure lockouts, I went aww-haa lol ordered high wind should kits for all the units, Problem solved never had an issue with that location ever again.
As a 'civilian' who likes to watch your videos, I'm surprised the industry hasn't incorporated gauges and temperature probes into the units themselves and the electronics, so that the board would know exactly the performance and a tech could later on know that there's a leak based on pressure loss over time, or what the head pressure was the night before when there was a failure, or see how the system was performing when it was working through a history download off a dashboard.
@@kingbilliam2654 Do they really? Can a modern system monitor it's own charge and other vital data points live? Because those things you mentioned seem like yes/no safety cutoffs, vs being able to monitor a leak and other performance in realtime from an Internet dashboard or a plug in readout. Heck, 20 years old, they could have done that 30 years ago. This is kilobytes of data, you know? Small stuff.
Almost 100% it tripped the freeze stat because of the filter blockage and the 407 taking way too long to even out so it probably froze the evap coil. That would explain why both comps were locked out.
I agree with you, this particular unit is overdue for replacement. Or at the very least, new coils; but the question of diminishing returns rears its ugly head again. I'm a huge proponent of "repair over replacement," but sometimes it's just not worth it.
didn't you say it out loud at 13:30? Only one freeze stat, plugged filters, so the evap gets cold, set the freeze stat and locks out both compressors at once.
If this was me, I would have confirmed which lock out you had. I also would have ran it without pulling filters, ect because I’d want to see what it was doing at the conditions they had. Also, if I saw low superheat and high subcooling then I might have tried to weigh out the gas and make sure you weren’t overcharged & then weigh it back in. I know you pressures weren’t crazy high but it’s just a way to confirm you charge was correct if you weren’t 100% sure. Troubleshooting units outside of their typical life span that are in rough shape are fun haha
Notes to customer: Unit tripped on high head due to being broken ass pile of bullshit running on tech provided spite and tears. Replace or fuck off IDC lol. These are the things that go through my head when dealing with stubborn customers.
maybe a brownout or phase loss stopped the fans/blower, assuming they're single phase. the compressors may have kept on chooching, depending on building load/backfeed.
Did you check the blower amps because the adjustable pulley looked kinda big Ppl like to tighten the belts by making the pulley bigger causing the amps to go over the rating, geting hot and going off on internal limit causesing the freeze stat to trip
NU22 has always done me well on Copeland (non trane related) older equipment. Have you noticed any differences between 407C and NU22 in the summer in terms of better or worse subcooling and or super heat?
And he said 22 starts out pretty low too or either the customers turn down the thermostats too low during the harsher of summer that could cause a lock out since 22 and 407 ain't really strong or efficient
Out of curiosity with the open top of the drain clean-out do animals or anything ever get stuff stuck into it? Just curious why it doesn't have a little vent cover.
High subcooling is the result of liquid backing up in condenser do to a number of reasons. System capacity is reduced when this happens. You can have high subcooling however from a restricted condenser as well. This happens because the head pressure rises more than normal and increases your ctoa. Therefor you'll have a larger temperature difference between refrigerant saturation and ambient which results in more heat transfer than normal conditions even though the condenser may be plugged or fan not operating as designed,ect. T.d. is everything. Also a good example of why you don't even want to check for system operation until you have confirmed your coils and filters are clean and you have correct system airflow, or waterflow depending on what you're working on
High sub cooling reading Also occurs when your condensor is extremely dirty or when condensor coils are brittle and not enough heat is rejected from condensor.
@@jac6541 subcooling is how low the temp is compared to sat temp. So the refrigerant could be backed up by a plugged part and is sitting in the coil for longer giving it more time to cool
R407c can cause high head pressure if system is low on gas or it hasn't been fully charged in liquid phase, the total opposite to what you would expect from say R22. Its a nightmare of a refrigerant
With that high if subcooling, and you being after the drier, I would think plugged drier. You were condensing 30° above amb. So nothing looks like a head pressure problem. I would say the r22 was over plugged drier.
It seems like it could be a fan issue to me. Could be a failing fan hence the different current draws, but I'd also be curious if the fan blade was loose as you noticed the one blade was a bit low... maybe it was slipping at certain temperatures
I wonder if during high ambient, the resistance in the fan motors decreases enough for them to go off on thermal overload.....and lower ended capacitors would exacerbate the issue
Thats weird. I've had like a few brand new York units at target doing the same thing saying freezestat but when they are tested all numbers are near perfect and the unit runs totally fine with no issues and the problem never returns. Still makes me question how a freeze stat only fails once and the issue never returns.
Man I really don't love those double stacked coils, so hard to tell how good you're cleaning it. Every one I come across I just assume is plugged between the two.
Two things. One you ran the rtu without the original filters. So, you didn't ru it with the same conditions as the lock out. Very well could have been low pressure, as dirty as the filters were. The other thing is high sc is not dirty condenser. That would be low sc. Looks to me like that ckt was over charged. High sc low sh. Just my two cents
@@HVACRVIDEOS my guess is the switch from mineral oil to Poe causing restrictions. However we both know high head pressure from intermittent condensor motor/dirty coil can easily cause those piston metering issues also. Have had lots of those units and still do.
You should always weigh in the refrigerant to the label. Once you remove that low charge high charge you can go fault finding Far too many techs chase their ass round and round rather than doing the basics first My first ever boss told me " never assume" best bit of advice ever.
I have no problems with 407c. I actually replaces both compressors about 2 years ago in that same model. That's the first i have heard of anyone having issues. Not to say techs don't. But sorry to hear that.
I guess Chris got a little hot. 😁 Don’t know where the conclusion of high sub cooling explained the condenser fins being dirty. Air flow problems would actually cause lower sub cooling. The liquid line restriction - that’s what will cause the high sub cooling.
If that second circuit is restricted then wouldnt your superheat be high too not 2 or 3 degrees, overcharged maybe, and dirty coil causes no subcooling not high subcooling right. Probally going off on high pressure on hot day. Not 70 degree day.
Sorry but I must disagree with you for a little bit. I think you actually had it pegged ..let’s put it in a equation.. A…… filters were from what I seen at least 75% plugged. B….. condenser coils were close to 30% On a package unit; if we have a restricted air flow over the coil that screws with our return temps an pressure . An while I will agree the condenser coil was not terribly bad that too is going to effect our Temps an pressures.. I am ( only guessing here) but I am thinking we had a possible coil freeze.. but even tho 22 is bad for us we have to admit 22 would run an work in impossible conditions…and the cooling curve over all is way different than 407 . .. Actually I hate 407 because it is?? I personally think the mix percentage is and was screwy from the get go. I will agree the unit is on its last leg but I think you DID peg the problem! it just was not a stick out like a sore thumb definite cause problem .. 😂 So I am disagreeing that you “didn’t” find the problem ❤ Edit… question?what would of been our results if we had left the dirty coil filters in to begin our troubleshooting 🤔🤔 I am betting we might of re-created the original problem.. but I have done the exact same thing you did. An pulled them out an had a retired HVAC friend with me that day an he said Man I wouldn’t do that . Why Bob??0.0 He said first your trying to find what caused the unit to lock out right ? Well yea but Bob I can see they are plugged an a problem… laughing. Bob was a mentor to me, and he had three times experience I had. Wish he was still alive. I wish I knew what he had forgotten over the years.
carriers are bad for a weak capacitor causing 1 fan to run backwards and then they act as an intake outtake fan and lock both out on high pressure. Sometimes it takes a gust of wind to start 1 of them backwards then by the time you check it the thing looks fine.
I love the fact that you are a younger dude doing old school troubleshooting tactics.
It's quite refreshing to see reason and logic applied to fixing stuff.
As a Canadian IT person trying my best to so the same, it's very refreshing to find others on the same track.
Your are good person please keep doing good work!
Yep, there's a BIG difference between a "wreak-nition", & a technician
@@coolingexperts1580 OMG wreak-nition is such a perfect term. Never heard that. Love it.
It’s always a disappointment and frustrating to see the wrong people hired into a position. Parts swappers , no troubleshooting ability.. wreck-nicians
Extremely thankful for your channel, my father makes a real good point when he says that my generation has a lot of tools that his did not, UA-cam being one of them !
I will discuss this on my Livestream this evening 5/1/23 @ 5PM (pacific) on my UA-cam channel HVACR Videos come over and check it out ua-cam.com/users/live6F1EzlQ4ZE8
@HVACRVIDEOS i know im late on this video. but ive found restricted filter dryer causing high head pressure and low subcoolong on these unit's, but both were locked out so maybe a fan, and i also check the temperature on the condenser fans with a temp gun. im in arizona so i have seen fan stop right in front of me and check the temp it was at 195⁰. its a habit of mine to check fan temps during PM'S. i know you're thorough, and i try to be thorough as well. question, how long have you been in the trade? p.s. i have a bit of ADHD . just mentioned that in case you notice my comment is all over the place. thank you for your videos. i watch them and try troubleshooting along with you and see if i can come up with a similar diagnosis. ill pause after you provide more info and see if my thought process is in the right direction . im 1 year in, and im learning every day in the video and in your videos. take care and stay safe out there!
Where is the dirt leg for the fuel line ? Be sure to check Condenser Fan Bearings. I used to check heat exchanger for holes. Could be time for a new unit.
The most challenging problems are the ones you can't duplicate.
Cars be like when you take it to the mechanic
That in any type of intermittent problems that can and will occur.
Or that it takes a very specific sequence of several different events to get a problem to occur!
In situations where there is lockouts but no definitive code to tell you why it locked out. I will always do the full visual of the belt filters etc. but will always run the unit in its current condition to see what my readings are with the dirty filters or whatever may look out of sorts. Can sometimes help take away some of the uncertainties.
What I was thinking. I would have left the dirt filters in there and see what the readings are.
Chris looks to me like you nailed the issue that was a good bit of dirt that came out of the condenser coil, that combined with nasty filters and a good hot day 85+ could have kicked it out on high head. You have to think about the difference an 85+ vs a 70 degree day makes. That or with the dirty filters and a cold morning could have frozen it out.
Great video! It always drives me nuts when I am not 100% sure of what causes a problem. Glad I am not the only one that talks to themselves when troubleshooting.
I do factory service on fiber optic equipment for the broadcasting industry. The first thing I do after a visual inspection for obvious damage is to clean the fiber ports. After I've done that, 90% of units go though the test procedure with flying colors. I won't contaminate my lab tools with cheeto dust or bong resin or boogers, or whatever else field techs manage to smear onto their fiber optic assemblies.
Damn. I love fault finding but it's SO frustrating when you can't replicate the fault!! I know the pain! But you did everything you could do!!
Enjoy the topic. As a thought consider NU22, it is a close match to R 22, but by no means is equivalent, BUT much cheaper. If the unit was even in good condition, I too would go r-22, but take a look at the TP chart as a comparison. As temps at outdoor ambient gets higher the similarities fade... In addition the only think that comes to mind for the CLO fault MAY be a corroded connection or something like that, but since I also doubt it, I still have to mention it. SHit happens when you are not there and like the person below me said, "It never happens while you are there. The CLO are also notorious for corrosion. My .02
MPT...
I’m always glad to see a video on one of these, since I got into commercial over 3 months ago it seems like 90% the equipment I come across are these Carrier Weathermaster/maker/takers. Though lately I’ve had a run of Lennox RTU’s.
I had one unit with lock out board.occasionaly was giving me same lock out symptoms with 407c. Finaly I by passed that board and never had lockout issue again.
I once had a low pressure cut off keep cutting out so I bypassed it, never had a low pressure cut out on that unit again 🤣. I'm just messing with you, this thought just popped into my head so I had to lol. Btw if I would be in your shoes I would probably do the same.
So, If you change the refrigerant you kind of, have to re - engineer the unit!! That takes a bit!! It's a lot of fun but it can be a pain! All in all, well done!!
you would see that dirty condenser on the high pressure gauge
Once you ran it towards the end of video and building load came down to normal, I agree with you that circuit one looks like restriction in liquid line/or orifice. The second circuit though may be normal. Really helpful if there's a manufactures charging chart for the fixed orifice systems, if not I use a universal total superheat chart for fixed orifices. Indoor wetbulb/ outdoor drybulb gives you you're target superheat. when load comes down to normal in the building its not uncommon to see low evap superheat even as low as 2 like you had, without a chart to work off of its hard to tell if you're overcharged or if you need to dive in deeper. I don't work on hardly any fixed metering devices these days, pretty rare where I work which is why the charts are a life/system savor
Wax clogs in the metering lines .. 407c and R22 both hate alkyl and mineral oils in high heat environments.
So im willing to bet that you have some wax junk in the metering device that really only shows up when the machine is loaded down in the heat.
ALSO those glassfloss filters are possibly overkill for someone who doesnt keep regular maintenance .
You are lucky. Where I liveR22 is banned since 2015. My heat pump is using R22. If there is an issue with refrigerant circuit, it must be replaced. As long as it is working, it may stay :)
Hello from New Zealand. my first thinking is that blocked filters give you a colder evap coil due to lower air flow therefore lower heat absorbsion, this then reduces suction pressure due to reduced superheat and therefore lower head pressure. I would lean toward anti freeze stat lockout before high head pressures. clean filters and better airflow will help resolve that possibility. How many sensors in the fieldpiece kit? Love you videos! Our R410a is slowly being replaced by R32. large VRV still R410. single splits are generally R32.
For stage 2 you said it may be restricted but your super heat was 3-4 f. Wouldn’t a restricted fixed office tube cause high superheat?
Thank you for your videos! I watch everyone!
It's funny this video came out because I've had 2 carrier systems do the exact same thing. One was a new install. Compressor was off on thermal. Upon reset there was no obvious sign why. Amp draw was good, pressures, tightened all connections, good temperature split etc... Still not sure what happened to this day.
I love how every condenser I’ve seen that you look at is almost always trashed. Even new ones you get are sometimes trashed.
Your clue on this one is the control wiring. The freezer Stat cuts off both compressors. Since it's the only safety that kills both, that's the issue. Can't prove it with gauges, but I'll be dollars to doughnuts that the coil froze up, triggered the freeze stat, and Bob's your uncle.
First stage is a wild card because of the 407C so the numbers are goung to be slightly off. Second stage with a sh of 2 doesnt really tell me there is a restriction in the fixed orifice. These units are notorious for restriction in fixed orifice but it's usually accompanied by slight or heavy frost at the orifices. Bottom line is the C coils are junk and the entire unit should be replaced. Great video!
Condenser fan amperage increases when the cover is fully on. That one condenser fan reading 1.3a may actually be running above fla. Great vid!
Good point
it should be lower current with cover on, because it makes more resistance and lower total air flow, which takes the load off the blades and motor, which in turn increases rpm somewhat.
the current will nearly always go down, unless it's some ECM cruft or something that adjusts speed to keep CFM the same.🤓
@@throttlebottle5906 That would be correct if we were talking about a centrifugal blower like you’d see in the evaporator section. With an axial fan it’s the opposite. Applying more static/resistance to the axial fan increases the load on the motor increasing the motor’s amperage. I’m also assuming that were talking about non ecm or the typical psc motor.
Nice video,i am wondering if when the stage one compressor was replaced with 404R they didn’t purge while brazing and drier currently have a restriction
How would a dirty condenser cause high subcooling? If you're not rejecting enough heat with a dirty condenser then you would have low subcooling
The way you started the video; *don’t shut the AC power off* ; thought maybe this Carrier system had alarm / error code memory, (circuit board module). (Which would be a unique Carrier system for the year you indicated). 😳
Have had good results w/ 422D....427A has been an issue 8/10.....
Chris, have you thought if a high-wind incident, on this unit, caused the fans to spin backward causing the lock-out from high-head pressures? I had a few problems with Sportsmen Outdoor Store and I had the same type of issues. For the life of me, everything checked out, I came back 3 times in one week, and on the last visit I was on the roof taking a break just going through everything in my head, and just then a 60mph gust knocked me off my feet, I swear I was in a tornado and could not stand back up for about 30 minutes until everything got back to normal and herd A/C units dropping out like flys, all on high head pressure lockouts, I went aww-haa lol ordered high wind should kits for all the units, Problem solved never had an issue with that location ever again.
I’ve had those clo boards lock out after power outages and or power surges
As a 'civilian' who likes to watch your videos, I'm surprised the industry hasn't incorporated gauges and temperature probes into the units themselves and the electronics, so that the board would know exactly the performance and a tech could later on know that there's a leak based on pressure loss over time, or what the head pressure was the night before when there was a failure, or see how the system was performing when it was working through a history download off a dashboard.
@@kingbilliam2654 Do they really? Can a modern system monitor it's own charge and other vital data points live? Because those things you mentioned seem like yes/no safety cutoffs, vs being able to monitor a leak and other performance in realtime from an Internet dashboard or a plug in readout. Heck, 20 years old, they could have done that 30 years ago. This is kilobytes of data, you know? Small stuff.
Great video. Rookie question, why didn't you probe the leads of the lockout boards before resetting the unit? That would have given you a hint
Is it possible a pressure switch can be starting to fail ?
Don't forget that CLO board also reads compressor amps as well. I would've checked compressor amperage see if it was on the higher side.
Can you make a video or explain further how the switch from r22 to newer refrigerant causes issues?
Almost 100% it tripped the freeze stat because of the filter blockage and the 407 taking way too long to even out so it probably froze the evap coil. That would explain why both comps were locked out.
I agree with you, this particular unit is overdue for replacement. Or at the very least, new coils; but the question of diminishing returns rears its ugly head again.
I'm a huge proponent of "repair over replacement," but sometimes it's just not worth it.
didn't you say it out loud at 13:30? Only one freeze stat, plugged filters, so the evap gets cold, set the freeze stat and locks out both compressors at once.
If this was me, I would have confirmed which lock out you had. I also would have ran it without pulling filters, ect because I’d want to see what it was doing at the conditions they had. Also, if I saw low superheat and high subcooling then I might have tried to weigh out the gas and make sure you weren’t overcharged & then weigh it back in. I know you pressures weren’t crazy high but it’s just a way to confirm you charge was correct if you weren’t 100% sure. Troubleshooting units outside of their typical life span that are in rough shape are fun haha
Notes to customer: Unit tripped on high head due to being broken ass pile of bullshit running on tech provided spite and tears. Replace or fuck off IDC lol.
These are the things that go through my head when dealing with stubborn customers.
maybe a brownout or phase loss stopped the fans/blower, assuming they're single phase. the compressors may have kept on chooching, depending on building load/backfeed.
I’ve seen too many of those compressor lock out boards faulty themselves.
I had one that had a loose terminal on the freeze stat that would intermittently fail.
Did you check the blower amps because the adjustable pulley looked kinda big
Ppl like to tighten the belts by making the pulley bigger causing the amps to go over the rating, geting hot and going off on internal limit causesing the freeze stat to trip
NU22 has always done me well on Copeland (non trane related) older equipment. Have you noticed any differences between 407C and NU22 in the summer in terms of better or worse subcooling and or super heat?
That foam gun looks very similar to the one sold by Nexgen.
You're up on this roof all the time!
Second stage had a slight overcharge first stage i would say weak valve on the compressor or wrong refridgerant
FreezeStat cuts both cutouts. 407c in circuit culprit. Cutout of freeze out at 44.8°.
And he said 22 starts out pretty low too or either the customers turn down the thermostats too low during the harsher of summer that could cause a lock out since 22 and 407 ain't really strong or efficient
@@prettycureforever7102 check where the 407c circuit starts out at.
Awesome video Chris....thanks for helping make the trade just that much better
What do the professionals here think about the "soft-start" devices for residential a/c units advertised on the internet and other youtube videos?
I'm not a fan of most of them
Wondering if you have a bad indoor fan motor tripping on thermal overload?
Out of curiosity with the open top of the drain clean-out do animals or anything ever get stuff stuck into it? Just curious why it doesn't have a little vent cover.
wondering how high sub cooling(cold refrigerant) equals dirty condenser?? metering device problem..........
I thought high subcooling meant that the condenser was overachieving by cooling the refrigerant too much, not being plugged up, TIL
High subcooling is the result of liquid backing up in condenser do to a number of reasons. System capacity is reduced when this happens. You can have high subcooling however from a restricted condenser as well. This happens because the head pressure rises more than normal and increases your ctoa. Therefor you'll have a larger temperature difference between refrigerant saturation and ambient which results in more heat transfer than normal conditions even though the condenser may be plugged or fan not operating as designed,ect. T.d. is everything. Also a good example of why you don't even want to check for system operation until you have confirmed your coils and filters are clean and you have correct system airflow, or waterflow depending on what you're working on
High sub cooling reading Also occurs when your condensor is extremely dirty or when condensor coils are brittle and not enough heat is rejected from condensor.
@@jac6541 subcooling is how low the temp is compared to sat temp. So the refrigerant could be backed up by a plugged part and is sitting in the coil for longer giving it more time to cool
R407c can cause high head pressure if system is low on gas or it hasn't been fully charged in liquid phase, the total opposite to what you would expect from say R22. Its a nightmare of a refrigerant
With that high if subcooling, and you being after the drier, I would think plugged drier. You were condensing 30° above amb. So nothing looks like a head pressure problem. I would say the r22 was over plugged drier.
Awesome video, great information, thanks !
Good job Chris, Might end up buying one of those Dad hats later on, after I figure out my budget, Because of Bidenflation.
It seems like it could be a fan issue to me. Could be a failing fan hence the different current draws, but I'd also be curious if the fan blade was loose as you noticed the one blade was a bit low... maybe it was slipping at certain temperatures
I wonder if during high ambient, the resistance in the fan motors decreases enough for them to go off on thermal overload.....and lower ended capacitors would exacerbate the issue
Is it possible that either the low or high pressure switches are getting weak?
Thats weird. I've had like a few brand new York units at target doing the same thing saying freezestat but when they are tested all numbers are near perfect and the unit runs totally fine with no issues and the problem never returns. Still makes me question how a freeze stat only fails once and the issue never returns.
That 1 fan seems to be slower than the other. You said was same motor.
Could it lockout if the lockout board read too high of amps on one of the compressors?
I think those lockouts will only go off on low to no amperage
Great Video. Thank you for sharing
Man I really don't love those double stacked coils, so hard to tell how good you're cleaning it. Every one I come across I just assume is plugged between the two.
If the thermostat was calling for cooling, would it not read 0 volts?
I’d check pressures with filters in first
You had the cover open air was bypassing the condenser
Two things. One you ran the rtu without the original filters. So, you didn't ru it with the same conditions as the lock out. Very well could have been low pressure, as dirty as the filters were.
The other thing is high sc is not dirty condenser. That would be low sc. Looks to me like that ckt was over charged. High sc low sh.
Just my two cents
20° sc is normal on those 7.5ton carriers. Work on that same model all the time and when recharged to factory charge it’s usually right at 20°.
why did you mix the refregratant 407c on st1 R22 on ST2 should the unit have the same on both stages
Is it just fixed orfice metering devices that you had trouble with R407c?
yes Ive had good luck with 407c on txv systems
@@HVACRVIDEOS my guess is the switch from mineral oil to Poe causing restrictions. However we both know high head pressure from intermittent condensor motor/dirty coil can easily cause those piston metering issues also. Have had lots of those units and still do.
I would probably weight in the charge for both circuits especially 2nd stage
You should always weigh in the refrigerant to the label. Once you remove that low charge high charge you can go fault finding
Far too many techs chase their ass round and round rather than doing the basics first
My first ever boss told me " never assume" best bit of advice ever.
Can you do a training video on leak repairing R290A units?
Why didn't you patch up that square opening in the service door I see that on all carrier units
Did you say y1 and y2 were using only one wire to control both circuits,?
The one near the open service door is drawing more amperage its moving more air
Where is the main control board? Errors? Not a fan of Carriers. Pretty large open hole cover there. Dual layer condenser coil? Dirty in between?
What kind of oil you got running with that 407c?
POE oil
I have no problems with 407c. I actually replaces both compressors about 2 years ago in that same model. That's the first i have heard of anyone having issues. Not to say techs don't. But sorry to hear that.
I guess Chris got a little hot. 😁
Don’t know where the conclusion of high sub cooling explained the condenser fins being dirty. Air flow problems would actually cause lower sub cooling.
The liquid line restriction - that’s what will cause the high sub cooling.
Can you list some specific things that would be criteria for deciding when a 407C conversion isn't going to work well, as in this case?
Can you go to 22 from 407c with the poe oil
I find when these are locked out and you can’t find an issue you will end up coming back to change a condenser fan motor sooner rather then later.
perfect time to use r422b like everyone else.
By the looks of that condenser, it looks like the fins are delaminating from the coil.
If that second circuit is restricted then wouldnt your superheat be high too not 2 or 3 degrees, overcharged maybe, and dirty coil causes no subcooling not high subcooling right. Probally going off on high pressure on hot day. Not 70 degree day.
Has anyone ever in the history of HVAC ever checked return air ductwork?
Try using MO99 in place of R22
Can't wait to get off work, then I catch myself watching others work, WTF ??? LOL
My app crashed and caused no sound. Really thought you went 3 for 3 there 😂😂
No i triple checked this one....
@@HVACRVIDEOS 🤣👍🏾
I would of knocked the cinder block down the return.
Just placed an order at True Tech Tools and used the BIGPICTURE discount code - thanks!!!
Thanks for the support Joseph!!
Uda man! Thanx for sharing!
finding that needle in a hay stack. just slap a new one if not move to the next call
Sorry but I must disagree with you for a little bit. I think you actually had it pegged ..let’s put it in a equation..
A…… filters were from what I seen at least 75% plugged.
B….. condenser coils were close to 30%
On a package unit; if we have a restricted air flow over the coil that screws with our return temps an pressure . An while I will agree the condenser coil was not terribly bad that too is going to effect our Temps an pressures.. I am ( only guessing here) but I am thinking we had a possible coil freeze.. but even tho 22 is bad for us we have to admit 22 would run an work in impossible conditions…and the cooling curve over all is way different than 407 . .. Actually I hate 407 because it is?? I personally think the mix percentage is and was screwy from the get go. I will agree the unit is on its last leg but I think you DID peg the problem! it just was not a stick out like a sore thumb definite cause problem .. 😂 So I am disagreeing that you “didn’t” find the problem ❤
Edit… question?what would of been our results if we had left the dirty coil filters in to begin our troubleshooting 🤔🤔 I am betting we might of re-created the original problem.. but I have done the exact same thing you did. An pulled them out an had a retired HVAC friend with me that day an he said Man I wouldn’t do that . Why Bob??0.0 He said first your trying to find what caused the unit to lock out right ? Well yea but Bob I can see they are plugged an a problem… laughing. Bob was a mentor to me, and he had three times experience I had. Wish he was still alive. I wish I knew what he had forgotten over the years.
All those carrier units suffering from restrictions on the fix orifices for next time
Awesome video
Have you used the R32 refrigerant yet?