R-22 and R-410A Refrigerant Operating Pressures on Air Conditioning Units!

[Music] hey guys this is AC some perspective that I was looking at or what are the normal operating pressures for r22 and r4 tonight in comfort cooling systems so we're talking about packaged units we're talking about split systems we're talking about single speed mini splits not necessarily inverter style ones so we're going to go ahead and go over with the pressure parameters are okay and I'm going to discuss the different things that affect those pressures for the high side and the low side so before we get started I just want to explain this gauge right here is going to tell you what's happening at the indoor coil in cooling mode and this gauge right here is going to tell you what is happening at the outdoor condenser in cooling mode all right so this here always have to be above 32 degrees so you have a out outside ring which is pressure and green indicates r22 saturated temperature you have a saturated state at the evaporator coil right in the middle the evaporator coil you have a saturated state right in the middle of the condenser coil the saturated state is where liquid and vapor both exist at the same time and that's happening right in the middle of both of those coils so a pressure will line up with a temperature r22 or if it is r410a which is the pink ring right here and that will tell you what the temperature is in the middle of the evaporator coil while it's running even though your gauge that's hooked up at the outdoor unit so let's just look at this real quick if we have let's just say 55 psi G and we follow over to the green 30 degrees then that means that our evaporator coil is freezing so if you have let the system run for 5 to 10 minutes and you see that the actual temperature of the evap coil is 30 degrees then that might be that you have a problem right there okay that could be a dirty filter or low blower speed the blower could be broken you could have an obstruction in the duct you know you could be low on refrigerant you could have a a clog in a liquid line heading to the evaporator coil of a bunch of different things okay but basically that means that you are not operating correctly because you're below freezing and that evap coil is going to glad and free solid all right likewise with r410a if you have a hundred psi G then 100 psi G is right below 32° and/or for today and these that coil is going to end up freezing that means you're low on refrigerant or some other issue with air flow or a restriction in line now the outdoor coil the pressure there can get affected by the rate of heat rejection okay that means that you have if you have a lower seer outdoor condenser such as a r22 system that is operating at 275 psig on the high side that either the fins are really dirty or they're broken down or it's maybe an easier outdoor condensing unit which is a seasonal energy efficiency rating that means that the amount of coils is very very small a lot of times as eight years only have two sides with the coils and you know it can also mean be the bushes or right up against the fins but anyway if you have 275 psi G and then you bring that in and what you're looking at is about 124 degrees for r22 the middle of the condenser coil and then it's just going to be however many degrees below that maybe it's maybe a hundred and fifteen or something like that on the liquid line that's a very hot line coming back into the indoor pool alright so the head pressure has to do with how much fin is available and the amount of heat rejection that's possible due to say how many passes there are on that upper unit and will kind of shape those aluminum fins uhrin if you have a more efficient larger system then the head pressure will be lower so so you have an R 22 system that has maybe 180 psi G on the high side that might be a 14 Cerre or maybe a 13 C or something like that on a 75 degree day maybe but if you have 180 psi G and you bring that in and you're looking at about 94 degrees for r22 that's the temperature it is in the middle of the outdoor unit okay so this is going to vary depending on the outside temperature and the amount of fins but really day to day it's changing due to the outdoor temperature so this low side gage would be more of a consistent number because humans are comfortable anywhere from say 68 degrees inside the house to maybe say 76 degrees all right maybe the average would be about 72 degrees so it doesn't vary as much as say the high side does so this way we can kind of start pegging some numbers down over on the low side gage so for r22 what we're looking at is about anywhere from 60 psi G up to about 85 psi G so the same system could operate anywheres along those pressures depending on the day now I will say that typically you're going to find the low side pressure for an R 22 system at about say at least 64 PSIG the thing is sometimes you're working with capillary tube systems and those tend to be a little bit lower for pressure on the low side gage and that is a metering device that looks just like this it's a small line instead of a piston inside this orifice chamber that looks like this so sometimes the cap tube systems are a little bit lower on the psig all right but most of the time you're going to be finding anywhere right around 64 or 65 psi G up to about 80 81 psi J okay but I'm extending the range a little bit so we're saying 60 to 85 psi G but most of the time it is about 65 psi G or 64 psi g2 81 psig okay most of the time and that has to do with the temperature outside affecting the temperature on the liquid line as it heads in and has to do with the indoor wet bulb temperature okay if it's hot outside and has a high wet bulb inside the house then the pressure is going to be higher on the high side gauge because this evaporator coils trying to battle humidity while it's absorbing all this heat as well on a cooler day you don't have much of a wet bulb you know the wet bulb temperatures a lot lower and the liquid line is coming into the evap coil core you might be at sixty seven PSIG okay right in here on the r22 system so those numbers that I'm giving you are above 32 degrees and they are typically not much higher than say 50 0.5 or 51 degrees on the evaporator coil alright so that is r22 now let's go ahead and look at our for tonight on the low side gauge okay your lettuce pressures are you going to find on a system typically it's going to be about 105 right here if you bring that in it's about 33 degrees saturated state for r410a now typically you're going to see higher than that you know typically you're going to see maybe around 110 or higher okay because that's a right around 34 35 degrees for all four tonight at the evaporator coil and a lot of times you're going to see right around 40 okay the closer you are to a 40 degree saturated state is going to be more room line to the average but once again you're looking at about 105 psi J up to about 142 psig if you bring 142 psig in you're looking at about 50 maybe about 50 point five degrees saturated state in the middle of the evaporator coil so anywhere is in that range depending on the outdoor temperature and the indoor wet bulb temperature but most of the time you're going to find with or for tonight systems it's going to end up being right around 110 to about 136 psi duty or so somewhere around in that range is going to be the most the time it sits around in that range right there I do want to say though while I'm doing this video on the pressures okay I'm giving you a range of pressures that the vapor side is going to normally look like you definitely want to avoid just trying to charge a system by pressure only okay it's not going to be accurate enough you have to use say the super heat charging process if you have a piston and I'll give you a friend's that's why you could have 75% of the days when the system is operating and it's and it's okay all right the system is cooling fine you don't really notice a difference but the problem is on cooler days you actually may not have any super heat on the evaporator coil and there's no way for you to tell if you do or you do not have any super heat on the evaporator coil if you're checking with pressures just do you know without doing the super heat charging process if you don't have super heat on the evaporator coil and that means you don't have super heat getting back to the compressor and that means you have liquid slugging the compressor all right it's not going to be all the time but it's going to be on the days that like I said our cooler and the wet bulb temperature is lower in the house the temperature is lower in the house on those days you're going to be possibly doing damage to the system so you got to be able to make sure that you have an accurate superheat across the evaporator coil for the compressors and that's why you can't charge a system by pressure only and just kind of rules a thumb and things like that you have to use super heat and sub boring charging process that will get you the most accurate the most efficient and the safest for the compressor now just so you know I'm going to have the super heat and the sub cooling playlists linked in the description below you're still going to need to charge or check the charge of the system with the sub cooling process which is done on the high side gauge if you have a thermostatic expansion valve that looks like this at the inlet of the evaporator coil and you have to use the superheat charging process if you have a piston that looks like this or a cap tube system that looks like this you should be able to find the type of refrigerant on the outdoor unit rating plate on the output compressor and also on the thermostatic expansion valve if there is one you can also use the pressure temperature correlation when the system is off to determine what refrigerant is in the system now on to the high side gauge if you're looking at r22 which is the green and then you have all four tenets to think all right if we were looking at r22 first for the pressures this is going to vary much much wider right of a range people are going to all be used to different ranges because of the equipment that they're working on if you have an r22 system you could have say you have one that has fins that are really deteriorated you might be all the way up at 325 psi G which is really really high all right but normally they're going to be lower a lot of times r22 systems you're going to find below 200 psi G you might find them at 180 hundred and sixty psi G 200 psi G but say you're working on a geothermal system that's really really efficient has a high seer rating you may be down at maybe even 125 or 145 psi G you're going to be down a lot lower with the higher seer ratings because they're able to reject the heat a lot easier if you have a head pressure that is all the way up at 300 or 350 I mean that that units on its last legs is having a hard time being able to reject the heat and is not very efficient compared to one with a much lower head pressure in reference to or for tane systems you might see a head pressure of maybe 230 on a really really cold day with a higher seer air conditioner maybe a 16 seer or Seventeen's here but most of time you're going to find them in the range of maybe about 275 you might find 13 seers somewhere in the range of say 300 anywhere to take 285 to 325 like I said this is going to vary it really depends on the equipment you're working on the seer rating you're working on just your environment where you're located at 14 C or 16 seer you might find at 240 PSIG on a cooler day and you might find that at 300 or 310 or something like that on a hotter day but once again you can find them higher you can find them lower depending on the seer rating the higher the seer rating the higher the seasonal energy efficiency rating the lower the PSIG will be and the SE the smaller the unit and also the smaller this year you're going to see the head pressures be a lot higher all right but once again you need to check the refrigerant charge with the superheat and the sub corn processes sub corn takes place on the liquid side and super heat takes place on the vapor side check out those videos and reference to how to check the system properly with the superheat and sub pouring charging process I also link some of the tools I use in the description below sometimes people ask you know what tools I'm using and all that type of stuff as well hope you enjoyed yourself and I'll see you next time at EC service tech Channel you

Channel: AC Service Tech LLC

Views: 764,851

Keywords: acservicetech, repair, maintenance, how to, fix, hvac, hvacr, how do you, 410a operating pressure, 410a refrigerant charging, 410a refrigerant, r410a test, r410a vs r22, r410a refill, r410a pressures, r22 charging procedure, subcooling method, superheat method, superheat process, subcooling process, air conditioner pressures, temperature, temp, pressure temperature, pressure temperature chart, pressure temperature relationship, charge, check, gauge, gauges, test, level, amount, freon, 410a, a/c

Id: uEs99SSKjgE

Length: 14min 56sec (896 seconds)

Published: Sun Apr 02 2017