Why Your AC Won't Cool (Piston Replacement Guide)

hey guys we are back at this job where um i diagnosed possibly a restriction in the metering device and we're back to replace it or at least make sure we have the right one so right now i'm going to turn this on so i can pump it down get up in the attic and open it up stick with me if y'all remember this one from that instagram post that nobody seems to know what exactly happened this was just spewing out refrigerant i took off my probe and when my probe came off apparently the schrader was damaged and the refrigerant was just spewing out like there was nothing there there was a probe in there they're just it was just damaged and i had to get a removal tool on it as fast as i could i did change my o-rings in my my probes recently i'm only putting one on the suction because all i'm doing is pumping down today's job might be very easy intend to open up the system up top check the piston um and i'm gonna start off on the suction side here and close this down i'm gonna check the piston make sure it's not clogged i have the correct one with me so we're gonna make sure we have the right one i was having trouble getting the right txv because they couldn't tell me if it was sweat or bolt in and these are actually both i just didn't have a good parts guy to tell me hey this is the right one so i got the piston yes you're supposed to close off the liquid line first i'm going to open that up just a little bit i do it that way so i can close it off quickly when i need to closing off the liquid line now that's going to be all the refrigerant that i can pump down up here in the attic and something i wanted to point out this little screen normally goes in right before the piston or txv obviously it is it was left out so not only am i checking the piston i'm checking checking the size of the piston i am checking to see if it's clogged y'all forgive me if that's a lot of noise but i'm going to leave the fan on because it gives me a little bit of air circulation piston is right in here see how loose that was you don't have to make those super tight a teflon seal in it be careful here pressure left in the system y'all forgive me there was wind noise but um i'm gonna put you back over here i'm about to pull that piston out okay i know that the um piston that they gave me that they said is the right size is a 67 and y'all might not be able to see that but that is a 57 so that was not the right size piston and um like i said that's going to be hard for y'all to see it is a 67 now we got to put it back together okay I got to make sure I have correct one sure I have my tip on seal in place always tighten that with your fingers because this is aluminum if you cross thread it you're gonna ruin it real fast you know that little that little piece here that's it but because we opened up the system zero pressure in it we're gonna have to replace the dryer okay I have already removed the shredder if y'all can see where I'm tapping my finger over here on over here on the suction line i have that nitrogen turned on it is valved off right here let me see we're going to turn this on turn this on make sure this is turned off and then we turn this on all right so we got nitrogen flowing and i don't have a ton of it so i'm going to solder this out or sweat it out and put another one piece of solder down there i have a big old chunk of solder right here that um it's not going to let me go ahead and just push this on so i'm going to have to heat it up and get it to slide on we'll solder it up get my solder ready all right let's put this right here where i can see it because i'll go looking everywhere for it the truth is it probably already has enough solder on it just a little bit more okay this is still a little bit hot i'm going to have to wait a little bit i try to heat that up just a little bit just a little bit get that to slide in just a little bit more i'm putting whatever it does look like i have some pressure let me um i'm gonna go ahead and holy smokes it's hot i'm gonna go ahead and put my put this on here so i can pressure test or bubble search anyway pressure we can open up the suction side i don't have a ton of nitrogen y'all can see that pressure i'm up to like 84 psi that's gonna be enough to test this system's gonna run so much better i have it valved off i have 167 psi and right now we are looking for bubbles don't belong all right this is just going to be nitrogen other schrader core replace that when we're done in my opinion if you remove a schrader core for whatever reason go ahead and replace it is done looking i'm looking for these these are my new um valve core removal tools you saw me take the end out of that one this one here on this side let's go ahead and valve that off that is for micron gauge this i like to pull a vacuum on one side the vapor side or i don't want to call it suction line because when it's a heat pump it's a hot gas line i mean when it's running in heat so better just call it the vapor line and we're going to put another one of those on this side because we have removed the schrader cores it will pull a vacuum much faster and when you have six calls in a day like i do today that makes a difference to turn on i hadn't used this pump in a while let's see how it does i'm not sure y'all can see that but i'm really just getting started down to 500 microns okay five excuse me five thousand five thousand five hundred six thousand is going up just keep an eye on y'all forgive me was getting a bunch of phone calls i mean i am booked all day today and tomorrow this is memorial day weekend i'm probably going to be working all weekend but bring it on i've been needing to work this was having a little trouble pulling down to 500 microns pressurized and bubble searched everything again and i'm convinced in trouble with these valves sometimes it's really hard to tell so so i got it to um like 750 microns let it sit for a while and then opened it up i know crucify me right y'all forgive me if there's lots of noise i'm right next to a condenser that is running we are almost done i'm gonna do that the other side i'm gonna turn this off right here and we have this open this open and we're gonna bleed this a little bit if i can there we go should come on i'm sure you can see that but i have a head pressure of 298 suction of 88 this is a 410 system it's over 80 degrees up there we did not lose a ton of refrigerant but um i'm going to watch my sub cooling and my superheat i should have a moderately high superheat um probably close to 20 degrees and we do not charge by sub cooling when we have a piston we charge by super heat but you can use that to help gauge whether or not we're low on refrigerant and yes this thing needs a cleaning but already my pressures are doing better i am not measuring the amount of refrigerant going in because i quoted him two pounds now if it's three or four pounds i'm still going to charge him for two pounds that's why it doesn't really matter and y'all see my super heat is getting closer to 23 20 degrees my pressure is 131 psi that is much better than what i was getting a couple days ago much much better i'm gonna watch that for just a second five minutes let it stabilize and we might charge some more and i hope y'all can see this i have a head pressure of 334 sub cooling of 9.8 suction of 134 and a super heat of 13 degrees i am not charging anymore my super heat has gone down to 10 degrees and it's hot up there so i'm gonna leave it just like that the system is doing much much better i think before my suction pressure was like 115 112 to 116 and now i'm at 134.7 i know the system's going to do much better thanks for watching guys i hope you enjoyed if you did how about like and subscribe check out the store in the corner if you're interested in business videos how to run a business to start a business consider becoming a member that's why the membership is for and if you want to be an ACIQ dealer in fact I'm installing probably two next week there's a link in the description I'll catch you on the next one