"Unbelievable, that's all I can say" lol. You're very smart technician and very funny at the same time. Really enjoy your videos, keep them coming. Thanks!!!
Pull the charge, system is full of moisture and non condensibles. Have never seen plugged drier cause high head pressure. It’s just like having isolation valves on high side partially closed. Lower head, lower suction. I know r22 is expensive, but you had an OK from the customer to get it done. Don’t get me wrong, I enjoy watching your videos and learned a lot about residential installs, but sometimes, you surprise me good sir.
@@dreamer6508 That’s all good. However, the problem is definitely not in the drier alone and not in the undersized orifice. Problem is in quality of gas in the system.
@@dreamer6508 he’s correct. This system has all the signs of non condensables. Needs the full charge replaced, drier replaced, and a good vacuum pulled.
That condensing unit has to be pulling high amperage, even on a 95 F day the pressure is way high, at 380 psi R 22 is condensing at 150 F, this will be ok if it is 120 F outdoors! It did not look like it was 120 F that day? If it were 95 F that day I expect a 125 F degree condensing temperature! On a 12 F day I expect a 150 F condensing temperature as you have at 380 psi with R 22.
@@skidmarkman321 --- Only god knows what kind if gas(ses) are in that system, probably a few different types and some non-condensables too. With the price of R-22 it isn't worth the cost of making it right.
@@davidnull5590 Could the refrigerant be fully replaced with the current refrigerant in production? Will the system work with a totally new refrigerant? How much would this job cost?
For the money the customer spent on this repair the customer would have been better off getting a new system. At the end the compressor still sounded like crap.
@@jasonoak4564 They all want you to replace it. Money is made there, and it is how they make ends meet, right? Tech who put the wire in tab for me quoted $ 8000 for installing the most basic combo for the smallest space. I would get it fixed and use it for the next 2 decades. The cheaply made new units will die in around 10 years anyway.
There are non condensables in the system. I know it has a piston but if it had a TXV and a sight glass you would have a difficult time to clear the glass and as you added more gas the head would would keep going up. Same effect with a piston fed evap but with out the sight glass. Non condensables don`t do much to the low side but they drive the high side crazy.
Being 17 years old, would it be better to spend eight hundred dollars to replace all the r22 and have the compressor crap out in a year, or just help it limp along as long as it cools the house. Its way past time to replace system.
Your Vacuum gage should be at the unit not then pimp. With 1900 microns at the pump, it will be higher at the unit. At that rate it has moisture in the system and possible leak.
@@dogdiggingrj2089 Any condensing saturated pressure (temperature of 95f on the low side to 155f on the high side) is normal. Typically it’s the ambient temperature (dry bulb) +35f should be your condensing temperature (for an air cooled condenser.) R-22 would be 180psig to 400psig considered ok. If your coil is plugged, if your fan is wrong (or spinning backwards... it can happen) or if you have non condensibles (air, nitrogen, anything not R-22) or simply overcharged. Could even be undersized liquid line and oversized suction line. We want to see a cold sweaty suction line about 55 degrees, a hot discharge line under 180 degrees and a warm liquid line of around 90 degrees for AC. Hope this helps
@@georgesummerlin1602 wouldn’t be good. Assuming approach of 7 f, 155+7= 160f discharge air. 110f entering, 35f split. That’s a 50f dt. This is an extreme obviously. Can’t see a system running for long like this before going off on overload or seizing due to oil degradation.
Don’t want to sound like a keyboard tech, but the head pressure is way too excessive on this one Steve. Had the same problem the other day. Recovered charge and weighed in new charge. Unit ran like a champ afterwards.
There were definitely non-condensible gases in that system. I wouldn’t have added any R-22. Maybe convert the system over to a replacement refrigerant.
Regular efficiency condensing units condense at ambient plus 30 F degrees. Higher efficiency condensing units condense closer to ambient due to large coil surface area, they condense at ambient plus 25 F degrees. Example, on a 95 F day with a regular efficiency condensing unit would be ambient plus 30 F degrees = 125 F condensing temperature, convert to pressure for R 22 is 270 psi. The indoor coil I charge to indoor ambient minus 40 F. On a day below 95 F ambient you can block air flow through the condensing unit with newspaper, bring the head pressure up to 270 psi, this simulates a 95F day outdoors, then charge the indoor coil to indoor ambient minus 40 F degrees. I take the amp draw of the compressor to see how much amperage it is pulling, I look for 15 degrees F sub cooling and about 20 F degrees superheat at the compressor at the tail end of the cycle, just before the thermostat is satisfied, If it is hot indoors the auperheat will be high until the room temperature lowers putting less of a load on the evaporator. I look for a 20 degrees F temperature differential ( Delta T ) from return air compared to supply air. If it is humid indoors the 20 F desres Delta T will be les due to de humidifying the air first. once the air is not so humid and has cooled down the c=oild split will increase to 20 F degrees. Regardless of refrigerant used if the condensing unit is condensing at above ambient plus 30 F degress convert to pressure, it is overcharged or you have air ( non condensibles) in the system. This system needs to be reclaimed and evacuated, leave a vacuum pump on it all night and charge from a vacuum weighing in the charge is best.
You’re the man Steve. That being said, the Condenser was filthy as can be when you shoved that camera up to those slanted fins. I’ve washed about 30 units alone this year, due to that being the only issue.
I must say that this guy makes me laugh. I like this guy because he try’s so hard but he tends to jump to conclusions Never, never, never, add refrigerant to a system until condenser has been cleaned. it’s not for sure low on refrigerant, I mean gas, until you determine the cause of the high head pressure. Also, most indoor coils will cover several tonnages of outdoor unit, it the metering device that needs to be matched to the compressor output.
I was thinking the same exact thing. First thing that should of been done was to clean the coil. I’ve had a number of coils myself that didn’t even look dirty but after you clean them the airflow is night and day as well as significantly lower discharge pressure.
Remember, not to long ago he was cutting copper using a rt angle grinder with a cut off wheel; UNTIL someone sent him some free 1/2 and 3/4 snap cutters 🤣
Had a unit on its last let Tuesday, got changed out Thursday. Boss said go top it off with that old jug of 422b on top of whatever’s in there lol. Head pressure was in the mid 3s but she was cooling like a champ
Nice job Steve, the compressor valves sound like they might have been overheated and the high side being up could be a symptom of valves leaking by, unless it is a scroll compressor. Some of those are noisy. Thanks for great videos.
@@hughholt121 valves dont stick on a scroll. what could happen is the internal bypass is leaking from the high side to the low side. but that would typically give you a high suction and lower head
Most old school PT charts usually stopped short of 380 psig for R22. The head is way too high the lady may hear a bang in the night when the condenser ruptures.
@@dpt4402 For the longest time I calculated subcooling on Liebert units using discharge pressure. If you read liquid pressure, your sc is cut in half, but its actually true subcooling. Some people forget there is a pressure drop through the condenser and 15psi can make the difference between subcooling and saturation. If its hissing, its not subcooling. Always good to keep thinking about this stuff, we get paid well, our customers expect it.
That head pressure may of been high because he's checking the pressures with the cover off. At the end of the day the customer wanted cooling and now they have it. We can only do what they want to spend.
With that style of condenser, the cover makes no difference in the pressures as the condenser air pathway is unchanged whether the panel is on or off. He should have cleaned the condenser coil B4 attempting to assess the refrigerant charge. Definitely should have shown the pressures after the coil wash.
13:36 "We'll put a little jism on there when we put it together". Never learned that technique in my apprenticeship class lol. Love the old school flaring tool - looks like it has seen many years of use and still going strong! BTW - is there any part Steve doesn't have on his truck!
So what did we learn? Bring a cooler with a can of beer as your gauges and that line with the insulation is sweating it’s working and you save money on correct equipment and proper standards and laws. Wow 😮 this should be used as a training video of how not to do Refrigeration. Old school ways for sure
Are you sure they didn't mix Freons in there? 395 High side is way to high for R-22 no matter what the outdoor temp is. Plus when you added in Freon, did you use one of those "Drop In" Freon's like Nu22 or 407c? There's no telling what other techs already put in before you got there. You could have recovered what was in there, Flush it out with Nitro / R-11, and charged up with a consistent R-22 replacement (Conversion) since you already changed the filter drier.
The head pressure seemed awful high for just an incorrect piston and the condenser coil didnt look all that dirty.... Those Rheem/Ruud units look like there is a carpet covering the coil when they are not washed regularly. It might have been an optical illusion from the camera but it sure looked like the fan blade was running backwards to me which would have caused the high head pressure.
Subcooling means nothing on a piston metering device , superheat only .also 1900 microns at the pump means the system is nowhere’s close to 1900 , vacuumed gauge should be on the high side , vacuumed on the low side only , true vacuumed test .also clean the coil before adding Freon , high head low suction is non Condensable , dirty coil or both .
You're not supposed to charge a fixed metering system via subcooling, but subcooling is still very important, especially when trying to diagnose a system.
@@paulcrandall2534 explain how subcooling is relevant in a fixed office system , it will never read correctly so how can you use it as a diagnosis tool
@@8799crosby just picture yourself diagnosing a system with a fixed metering device and imagine what the pressures and temperatures would do under different circumstances. For example, imagine a system with low suction, high superheat, and lower than normal high side pressure. Is the system restricted or low on gas? The only way to know for sure, short of pulling and weighing the charge, is to measure subcooling. If it's low on gas, it'll have low subcooling. A restriction will show high subcooling. Another example, how about a system with a hot, over-amping compressor. The suction and superheat are perfect. The condenser coil is clean and the condenser fan motor is working ok, but the head pressure is way too high. If you went ahead and measured high subcooling, you could then determine this is an overcharged system with a restriction. These are just a couple of quick examples off the top of my head where measuring subcooling will help you properly diagnose a system. It becomes even more important when working on smaller refrigeration units with captubes, as opposed to residential AC. Regardless of the metering device, measuring both high side and low side pressures and temperatures will give you the complete picture on how a system is operating.
@@paulcrandall2534 that’s what don’t understand, if I charge via superheat on a fixed orfice system and my superheat is 10-20 , my subcooling would be 40-50 , which tells me nothing . Now on the flip side when I charge a txv system superheat will usually be between 10-20 when my subcooling is 8-12 ish .
@@8799crosby If you're on a fixed metering system and measuring a 10-20 degree superheat (which is a very large range btw), your subcooling will not always be at 40-50 degrees. There are many things that will affect subcooling. Outdoor ambient temperature, condenser coil condition, indoor load conditions, indoor fan speed, system charge, and lineset length are just a few things that will affect subcooling. Where you're measuring the liquid line temperature will also change your subcooling reading. Measuring at the condenser is very different than measuring at the evaporator. Same thing with superheat. Measuring at the TXV bulb is very different than measuring at the compressor. These are all things that you'll learn to pick up on as you gain more experience. These things become even more important when applied to medium and low-temp refrigeration systems. Here is a real world example. It's just a thought exercise. You get a service call on a freezer that stopped working. You diagnose the system and determine that the TXV failed and slugged the compressor; killing the compressor. You put a brand new Copeland scroll compressor into the system along with a brand new TXV. As the box reaches temperature setpoint (-10 degrees F), the superheat at the TXV bulb is about 6 to 8 degrees, which is normal for this system. You measure 12 degrees of superheat at the compressor. However, for warranty purposes, Copeland requires 20 degrees of superheat at the compressor. What do you do? I know how I would approach it, but remember, this is just a thought exercise. It's something to think about. This is the kind of level of thought and diagnostics you should be using while troubleshooting a system. I'm not sure what else I can say that will help you understand better. The only additional advice I can give is when you measure your pressures and temperatures, start measuring subcooling along with it. Do that to every system you hook your gauges up to. Especially during a PM. That will allow you to get readings on a system that is charged perfectly and working properly. After a while, as you gain more and more experience, you'll learn what pressures and temperatures to expect to see. You'll learn how subcooling reacts to different system and environmental changes. I will reiterate that superheat is more important as you're charging a system with a fixed metering device. But as you're diagnosing a system, adding subcooling to your measurements will allow you to see the full picture. Take a leap of faith and try it.
So what Steve found is that the installer upgraded the compressor from a 1 1/2 ton to a 2 ton, but never changed the piston to match and it ran that way for years? How about the evaporator coil? Should that have been originally upgraded to 2 ton also? The customer didn’t want to pay for that?
That tiny condenser is struggling to condense the refrigerant from that over sized compressor. Time for a new properly sized system. I cant imagine what their utility bill must be
Couldn't pull adequate vacuum = system leak. System must have been pulled into negative pressure at some point and air (non condensable) was pulled into system. Head pressure too high. Leak should have been fixed first or system replaced.
Agree. This lady paid for a number of needed repairs so if the coil or something else is leaking it may only run cool a month or so and then she needs to pay for a coil in this ancient mis-sized system. I’m all for fixing something instead of replacing but this looks like good money spent on bad. I would have recommended a change out.
The condenser coil was filthy. Couldn't quite tell what the condenser fan was doing; he didn't check the fan motor or capacitor. However, considering how restricted the filter drier was, it's most likely non-condensibles in the system that was contributing the most to the high head pressure. Once non-condensibles are in the system, your superheat and subcooling readings are meaningless. Pull the refrigerant, braze in a new drier, pressure test and address any leaks, pull a vacuum, then recharge with MO99 or equivalent replacement.
Steve I bet you cherish the jobs where your not on your knees or climbing around under a sink. I couldn't do it. It'd take a hydraulic jack to get me back up
Damn old man, you friggn called it off the bat with the lineset probably being clogged.. i would think that when the compressor was changed they got contaminated and stopped up the txv, filtter or piston if thats whAt itz got..
The piston is what meters the refrigerant into the evaporator coil and you're supposed to use the piston that's properly sized for the compressor. The wire is used to remove piston.
I wish you lived near my sister. Hers hasn’t worked right since it was new. The local ac company has been out there 4 times and they make every excuse in the book why they can’t figure it out. They charge her every time too.
I think that model reem was a bad design because I know three other people that had to have the compressor changed out including me so that’s five people all a few years after they were new.
@@Berzerk29 yeah, my friend said, it's not getting airflow and that's why not to tarp it. You're trying to keep snow and leavez put of it. It said, it will destroy your unit life early. I know my original unit 30+ years ago, came with a cover, but my parents never covered and it lasted 30+ years without ever adding freon.
Way to high head pressure something is way wrong there and im not an HVAC mechanic just refrigeration guy... mismatched evaporator txv for sure. Steve gonna make it run right
I replaced my old Honeywell round mercury thermostat with simple digital Honeywell thermostat. Now AC condenser unit and the fan do not run. Just the indoor fan comes on when I want AC to start. I had B Y G R W wires on old thermostat. AC is Ruud from 1988. No heat pump. Changed both capacitors on the outside unit. What could be the reason for no AC?
I agree with Brendan. You have wired the new thermostat wrong, or you have a bad thermostat. Go back and check your wiring. If you have to put the old thermostat back in.
@@BrendanN941 I had to call a tech. One wire was not fully in the cheap plastic tab. Even after discovering and fixing this first, the tech checked everything including the R22 levels. Putting the gyages in and off, both times my system lost some precious R22. I can't believe a tech would do that just for the sake of checking off boxes.
