 26.52 times your amperage on the capacitor divided by the voltage on the capacitor gives you your microfarads. Two train units here on a convenience store. This one right here is required 10 degrees subcooling 14 on it has the variance of 3. This one same thing rated for 10 but we're in 28. Here's where might be overcharged I was wondering if he had something intermittent going on because everything was looking pretty normal for the most part fan motors are rated for one amp pretty good on that say we're probably overcharged our biggest issue when it was hotter pressure probably hopped up there a lot higher that's 120 condensing temperature and I think we're about 80 out here so we're just a touch over we're gonna take some out and see how she starts to react superheats okay this is the TXV system so it's countering it but it's working that compressor a lot harder than it needs to condensers all clean so we got her hooked up everything's zeroed out start dumping a little liquid into it about a pound and four ounces amperage drop down to 11.5 the ambient's 85 out here tends to require give or take three degree variants let her stabilize for a bit we've got 10 degrees with the variance of three like I was saying all right so I already checked the capacitors when I was here last and I replaced the one over here so when you aren't a hundred percent sure what's going on and acting up I mean they start checking everything I start checking the amperages voltages cross contact everything already pretty well done on the service but now obviously something's acting weird especially when it's running so this is rated for seven and a half microfarad with a six percent variance we checked it under load we had 277 volts and point seven amps so point seven times 2652 divided by 277 volts comes out to a six point seven microfarad so we're under on our microfarad so that can be causing some drag on the motor let's go ahead and check that out the average on it that was right at one amp so point eight point nine to one amp which is exactly what the motor is rated for pretty good and change that got her sub cooling right where we want it at double check her power box here make sure all of our connections are good nothing's loose I like to check it ahead of time it's rated for seven point five and right at seven point five and I've checked my meter against my eighty seven five flute so I don't always trust some of these amp clamp ones power is off as always train professionals don't be going in here playing in here if you aren't one so let's see what this thing tests out at now this is a little interesting like I said I tested these out but I didn't test them under load seven point two three seven point five so it tested out fine on the meter but I did not test it under load I did this service it was cold outside so I couldn't really check the refrigerant pressures now today we're like I said 85 I mean that tells us that either the math is wrong or the board doesn't hold up under load so I would go with it doesn't hold up under load so there's your 2652 times your amperage on the capacitor divided by the voltage on the capacitor gives you your microfarads you always check out that red fish meter that's one of the few I've seen out there that can actually check it and I could have checked in my power factor with my amp probe meter so let's go ahead and kick us back on recheck our refrigerant pressures hopefully it didn't affect anything because like I said the amperage motor was fine so my thought process is maybe the motor was dragging a little bit and that would slow it down then that would make the head pressure go higher so let's go ahead and see where we're at here in a second while we're waiting go ahead and recheck the amperage still at one amp so right at our max for giggles let's recheck this capacitor now we're point seven about pretty much the same amperage as we have before pulled away from the contact or magnetic field on some meters can really screw with them now we're point eight that's the interesting thing of these flukes I noticed it takes its time to get where it's got to go but when it gets there it's accurate my amperage was a little bit off sometimes see how slow it is it'll hit eight here in a second probably yep so the amperage actually is a tenth of an amp higher and check voltage 277 that's the same voltage we have before so did the math real quick point eight amps times at 2652 then divided by the 276 volts comes out the point comes out to 7.62 blah blah blah so let's just say 7.6 and measured in a 7.5 so under the load that tenth of an amp there made much to the difference it's not much so I'm a million times of rushed 410a and you'll check it like I am right now at 8.5 we'll be like oh gotta go grab some refrigerant come back get your tank all set up everything good to go next thing you know you're where you need to be so we're shooting for 10 or let this run for a little longer guarantee it'll be right back at it again all right so we're checking the power factor we're on the common wire of the motor we're on L1 L2 the voltage go into the motor and our power factor now is between a 1 and 0.98 one's perfect so 0.98 0.99 usually they're rated like 0.95 so that capacitor is checking out pretty dang good so we're good on that out of curiosity to see what my amperage is now 0.99 so it's pretty much right in line with my fluke so 0.99 it would round up to one not bad this is the 50 the 52 nav it's a good little meter it just got it's got so many goofy things on it and basically like I said this thing's got AC and DC amps it's got wattage our factor frequency frequency through the clamp but it gets kind of goofed up depending on the amperage on the frequency it's got phase rotation it had a lot of crap on it so only problems I've had with it was like the battery door and then no place to put a magnet so I had to come up this jerry-rigging thing here and it's got the light there which is kind of nice and it's good for I think it's cat cats cat 3 up to thousand volts and cat 4 for 600 so it's actually more safe than my 902 fc here but you can just tell the difference in equality this thing they're both made in China yeah they're so embarrassed they don't even put that where it's made at it says Taiwan on the package same thing of fluke they don't they don't like to put it on there they charge you like USA prices they don't don't make it here so jumping back up here to the sub-cooling we're at nine that pressure is just a touch lower but like I said it's still coming in let it run for a little bit yet even if that and we're technically in spade it's back okay so we added two ounces back two measly ounces put us right back at 10.4 so it's still almost a pound and a half over the basseter issue there nothing stands out though none of this would probably create a humongous issue but it wasn't right and when we got up to say 95 definitely would put under a heavier load would have worked the compressor over especially since it was doing better now that today was a lighter load still gotta check temperature ice across the coil but far as the outside I mean there's some chance for you guys to see under load versus testing it out under load obviously makes a difference before we head back in for you new guys this is why I like the ball valves so I'm gonna valve off my high side here we're gonna dump that back into the unit so the only thing to be left is some vapor in that hose even though I use six foot hoses elementary to most but just want to point that out I do the same thing whether it be a small one but that's also why I make sure I purge each hose out through my middle hose that way I'm void of any contaminants or non-condensibles out of my hoses don't forget to tighten up your caps I don't know how many systems I go on they get hand tight and nobody tightens them any further and you don't have to go stupid tight just a little bit they usually say an eighth of a turn I believe snug it up and then a turn it's all takes brass brasses off you'll smash it the other thing sometimes I'll check is the caps on the unit itself which out it's got a funny looking nut so that one there that one there's a little bit loose so got them both there also guys when you have something random like this and you're trying to narrow it down what I'll do a lot of times I'll come out with the manager and show them where the units are at so they know which ones to look at I'll ask them was the fans running did the unit feel like it was running did it seem like it was blown on the inside the more information you can get from them the better you can build your case everything is detective work here especially when it's not cut and dry and there's a dead body a dead air conditioner laying on the floor you've got to go through and get all the clues and question the witnesses so to speak to get the case built as to what's wrong a lot of times it's just collecting clues so call us the doctor H back or the lawyers of age back I guess you're definitely are removing some humidity out of the air it goes up and then to the unit up here now I went ahead and check the thermostats made sure they can't turn them down any lower than 65 way we do stuff around here run it in metal then we insulate it you can see this obviously takes a lot more time and effort to run it in hard pipe so we've got some makeup here right there so we're bringing in a hundred percent outside air when it does run which could be causing us some issues close it a little bit and that's on a damper so I don't know how they get that wired take a look and see yeah it's definitely powered open like I said I'm just going to limit it down a little bit you can see it's cutting it down some that's going to help a little bit this unit here's finally came on all right so we got 55 degrees there it's off the run and around the corner let me check that back here this kind of got a mix of makeup air return air just kind of get more of an accurate reading 5575 let's just say 19 degree drop so that's pretty normal and this is the back one here coming down going through the 90 we got 54.8 so they're both performing about as good as you could hope for these are both ECM motors on them so I'm gonna say unless something weird is going on between a little bit overcharged a little extra outside air coming in then being right by the front door because this is a convenience store all this things combined together you know they don't have anything leaking filters are clean everything else side is clean I must say we're going to roll with it I did program the thermostats so they can't go no lower than 65 which I prefer about 68 or 69 but I don't want to get too low that's caught me in the back before so I'm gonna wrap this one up we'll just have him play it by ear see how it does and then we can kind of go from there