Nope, that’s the same info I found when googling. There should be a schematic inside the access panel where all the electrical is contained.
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- Thread starter nxhappy
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Nope, that’s the same info I found when googling. There should be a schematic inside the access panel where all the electrical is contained.
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With 420 running at a higher pressure than r 22, I would be willing to bet that is what is happening. On those hot days, you might be tripping the high pressure switch. It would be great if you could put a gauge set on the unit on a hot day.
Out of curiosity, is your unit labels is some way showing that it has be charged with r 420a?
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Out of curiosity, is your unit labels is some way showing that it has be charged with r 420a?
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I’m gonna have to talk to some buddies about the r420a. I don’t have any experience with it myself. I can’t even find a pressure/temperature conversation chart for it online and there is little documentation on the stuff.
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originally it was r22, and then the previous owners had it serviced and they swapped it to 420. I also verified with the tech. I think you are right, its tripping the HPS. Is it safe to remove that switch ?? Or does that prevent the compressor from killing itself LOL. It's been a few days now, AC running good and holding temp. It's been a little bit cooler outside.
Just a thought, but with them having change the compressor and swapped refrigerant, is it possible the expansion valve is playing a role in the problem at hand?
*Did they give you a printout if the superheat and subcool values when they checked out the system?
*Did they give you a printout if the superheat and subcool values when they checked out the system?
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OP said it’s been running and cooling for a few days now, it sounds like it was a lack of maintenance more than anything.
After trying to find info for 420a, I ended up on the EPA’s website for their approved replacement list. It seems it is only a replacement for r-12 in automotive and r-500 in chillers, industrial cooling etc. I did see R-22 being used in place of R-500 but the increase in capacity means the evaporator and condenser would be then undersized.
Could this simply be a case of mismatched components?
Could this simply be a case of mismatched components?
I understand that, but just because it does run doesn’t mean it’s working efficiently or correctly. Pressure and temp are correlated as you probably know, depending the txv may not be able to compensate or the original components could be incompatible with the refrigerant.
I’m looking at the EPA’s newest SNAP guidelines now trying to see if it’s even on the approved list for 22 replacement, as it wasn’t in the last revision dates 2011 that I pulled up.
I mean, we know 0 about the system. We don’t even know for sure what refrigerant is in it because the previous owner was the one that had it serviced.
it could be an issue with the txv, it could be a lot of things. Without actually seeing it and going over it, it’s just guessing.
This is true, but if it is using anything 420X it isn’t even an approved refrigerant to residential according to the EPA. Only R12 and 134a. Just looked it up. That tells me it’s off enough that the original system is incompatible, or at least part of it, unless they changed everything over for it which is doubtful. I read on another forum that the higher pressures had caused leakage among other issues.
Compositions of Refrigerant Blends | US EPA
it is for sure 420 in it ....
I’m not trying to be rude when I say this but how do you know ?
it is very possible that coils just needed a hose down. it is also possible that the capacitor was the problem, which I replaced. I still think its the super hot weather that over heated and tripped the compressor. The compressor looks like shit and it is from 2009. previous owners were retarded and didnt even have filters installed.
I will ask say I am not a guru, my brother is NATE certified so I could ask him. But I do know that if the components are sized for the refrigerant shit like this happens. Suction and discharge being off because the boiling points being different, txv not able to compensate, etc.
because i have talked to the service tech who has worked on this system for 2 years
Is he the one that changed it out or does he have paperwork? I’m asking because like someone else said r420 isn’t a replacement for r22.
Did they mean 410?
A dirty coil will absolutely cause The high limit to trip and shut the compressor down while keeping the fan running.
If you have a meter than can check microfarads you can test the old capacitor if you have it still. But if the capacitor was bad then it usually wouldn’t work sometimes and not work others
during the issue, the fan would not run, and the compressor would not run either. just air blowing out of the vents. as of now I can hear everything running properly. At this point the only thing "not new" would be the compressor and the electrical board, along with the thermostat. 100% for sure the system is running 420R. If that is an issue let me know.
Nope, do not bypass the pressure switch, bad idea. Your evaporator would eventually start to warm up anyhow as pressure rise. As for the other things, the old capacitor could be tested to verify if that was the issue. As I said before, I don’t know enough about the refrigerant you’re running to say anything good or bad about it. I just know that it sounds like your system was being pushed to the max on those hot days, which is around the times you mentioned the system shutting down.
I would be curious to see how the 420 compares to r22 pressure/temperature wise. It’s just concerning that there isn’t more info out there about concerting from r22 to 420. Makes me think personally that there are some issues with it.
Let’s stay analytical on this. If you would send me that schematic, I may possibly be able to tell you if the pressure switch dropping out would shut down the condenser fan and compressor as well.
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