HVAC Suction Line Accumulator Tank! How it Works!
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- čas přidán 20. 07. 2019
- In this HVACR Training Video, I discuss how the Suction Line Refrigerant Accumulator Works, Where it is located, and the Difference between the Accumulator and the Liquid Line Receiver Tank. I discuss why the Accumulator safeguards the compressor and how a mini-split works with a range of refrigerants inside. Supervision is needed by a licensed HVACR Tech while performing tasks as Experience and Apprenticeship garners Wisdom and Safety.
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Information in this video is intended for educational purposes only. Any work related to the topics in this video should be performed by licensed technicians or by apprentices under the supervision of licensed technicians. AC Service Tech LLC is not responsible for any possible damages or injuries caused by the use or misuse of any information provided. ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
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Man I'm still learning things at 70 years old. Retired electrician here but always had an interest in HVAC. You are a great teacher and I appreciate all of your videos.
Thanks a lot DC Rickerson!
The cut always are a great help for explaining the system.
Thanks a lot Anthony!
Best accumulator explanation I've seen. Thank you! The cutaways are great too!
I'm dealing with mini split install and this really helps. I did take a look at the compressor itself and they all have accumulators on the compressor itself.
Excellent teaching and experience. Thank you very much for your content. I’m definitely going to pick up your book. Thank you again.
I appreciate your note Anthony!
Best instructional videos on CZcams, hands down. 👍
Glad you think so!
Going through trade school right now. I'm more of a visual learner so getting this explanation with these visuals really clears up what I'm not understanding in my book. Thanks (:
Glad to help TheMuffinMan328!
Thank you sir, for sharing this information. It is very usefull. Greetings from Indonesia.👍🙂
i love your channel, thanks for this video!
Jhonatan, I really appreciate all your notes! I am glad you are enjoying the videos!
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Excellent!
Thanks a lot!
Great video thanks
Thank you for watching!
Rote, understanding, application, corrilation, the 4 steps of learning.
Thank you very much A D! I appreciate your comments!
thx v much. very clear
Glad to help Marwan!
Craig , your catching on about HVAC/R ... Lol ... Another good tutorial ... Much appreciated ...
Ha ha, the comparison between the receiver and the accumulator. It is something people seem to get confused on especially during their EPA 608 test, thanks Eddy!
Do you have any videos on reversing valve troubleshooting, or weak compressor valves? I know that these two issues tend to share a lot of the same symptoms, and are both more of the difficult issues to diagnosis. Your videos are always very informative and easy to understand, and if you don't have those two topics, I think they would be great additions to the collection.
Mark look up "acservicetech compressor valves" and "acservicetech bad compressor" thanks
Reversing valves are pretty easy. If it's leaking you will see a huge temp rise across your current suction ports on the reversing valve. (Suction in might be 40 degrees and common suction to compressor might be 60 degrees. There is always a small temp rise on a reversing valve. Don't be alarmed if you are picking up five degrees) If it's getting stuck you will hear it. It's hard to miss. It will probably also have a dead compressor and you won't realize the reversing valve is bad until you replace the compressor. Unfortunately, since reversing valves are pilot operated, the compressor needs to be running to shift them. Now replacing a reversing valve....that's where the real fun (not) starts! If you come across a compressor with blown valves and a reversing valve is present, ALWAYS explain to the customer that another device could have failed and caused the compressor to fail and you won't know for sure until it's running and then give them a repair and system replacement quote to protect your butt in case they go with the compressor replacement and you have to turn around and tell them they need to dump another $2000 into their heat pump.
Compressor valves are easy as well. Pump the system down and turn it off. If the low side pressure holds or climbs very very very slow your suction valves are fine. If the amp draws are low and your head is low and you know the charge is good (always pull it and weight it or pull and weigh in fresh if it's a blend) you have bad discharge valves. Suction valves act weird depending on how bad they are. Amp draws can be all over the place. The pump down test is best. If the compressor is running and your high and low sides are equal you have catastrophic valve failure on suction and discharge.
Great, great lesson!!! Love it. Tell please about difference between sizes of office devices. Tell please about type of txv. Also how to check if txv is clogged because of stuff from filter liquid dryer. Thank you 😊
All good topics, I would like to do some videos on TXV's and troubleshooting liquid line restriction problems in the future! Thanks Tapch MC!
Thank you for your wonderful video. This was so helpful. I have a quick question. I understand the purpose of small opening in the bottom of the J-tube. This small hole flashes the liquid refrigerant ensuring that only refrigerant vapor can enter the compressor. I am assuming a case where there is a sufficiently large volume of oil buildup with the liquid refrigerant mixture. Whenever the liquid refrigerant+lubricant mixture flows through the small hole at the bottom, due to the sudden depressurization it is supposed to flow only refrigerant vapor+oil. If there is a hole at the near the top of the outlet port, wouldn't the oil come out again and settle down at the bottom? In my practical case, I am interested in returning the oil with the refrigerant vapor to the compressor intermittently. Looking forward to your feedback.
When measuring superheat why wouldn't you take the line temperature AFTER the accumulator? Seems like a measuring after the accumulator would give a more accurate temp of what is going into the compressor.
Thank you for your videos and your book!
nice, so do we need add extra accumulator if our AC kompresor had already even it small in size attached beside the main compresor body?🤔😘☺🙂
It's also used in refrigeration w long line set runs
Absolutely, anywhere you may loose superheat before reaching the vapor compressor, thanks!
Hi Ac . you were saying that the accumulator is also used on ac systems that have long line sets . what would typically be considered a long enough line set where an out door unit built with an accumulator should be installed ?
Hey guys. Can you do a video on the science or theory of how a leak sealer is supposed to work? Much appreciated! Thank you for your videos!
Chip, thank you for letting me know what you would like to see!
Leak sealer doesn't work well and some of it gums up HORRENDOUSLY when exposed to oxygen, i.e. when the system is opened to atmosphere to make a repair. Use it as a last resort on equipment that is scheduled for replacement in my honest opinion. You will be ripping your hair out when TXVs and pistons start sticking left and right after a repair because some dingleberry launched a bunch of leak seal into the unit and you didn't know about it.
Is accumulator similar to refrigeration system with economizer?( expansion valve and float switch in it)
when you have to use the suction accumulator ....is it with the system greater than specific power rating ....... when to put it in your consideration during designing a system....thanks.
excuse me sir I have a question, as video said there will be more and more liquid refrigerant in accumulator how to handle it, and whether the oil will get into the AC system or just in compressor
What are the different types of suction line accumulators?
Not sure if you still monitor this but I’ll give it a shot. Cooling mode. 2-1/2t h/p. About 25° superheat on a 85° day. (New install). Compressor noisy,. Suction line going into the accumulator 20° warmer than the line coming out to the accumulator. From the accumulator to the compressor will even frost a while. Sounds overcharged yet the super heat is actually high. I’m confused. Somehow the accumulator has to be bogged down with refrigerant? (Note: line set about 60’ and Air handler is in the attic). Any ideas?
I carry a can of rustoleum on my truck just for accumulators and driers. I hate installing driers inside because taking a torch into any building, especially stick built built buildings, unnecessarily is a risk I don't really care to take (plus I'm lazy. The majority of burning happens outside so why force someone to drag their torch into an attic or crawlspace if you don't really need to?) so I always knock the burnt paint off a drier after and install and touch it up. If you take the extra 2 minutes with a spray bomb that drier will last forever. I also touch up the tops of accumulators that are beginning to rust when I do coil cleanings, replace motors, etc to keep them from rusting out. I have found far more leaking accumulators in my career than leaking driers simply because they are almost always covered in condensation.
In before the haters scream the drier needs to be as close to the metering device as possible. No, it doesn't. Also, many climates have heat pumps that spend more time in heat than in cool. Which metering device is more important in those scenarios? Also, OEMs are now factory installing driers in the condenser because too many hacks aren't installing them at all and those systems work fine. Seal up your linesets before you run them and dirt isn't an issue.
So what will happen to the liquid refrigerant that enters and stored in the accumulator?
My home girl just ordered me your hook make Sure you autograph it for me man it's the one going to hopewell in ny bro lol cant wait to flip thru it and step my game up
Hey Wild Man, what order number are you?
@@acservicetechchannel let me check
@@acservicetechchannel 114 655 or 115045 is the start of it off the order # I got one refrigeration book so far but wasnt yours the name ordered under a joceylin
@@acservicetechchannel 4742601 part of it
I just learned that we shipped that book on Monday and today is Thursday, sorry and thanks!
Sir
Why there is no suction accumulator in screw and scroll compressor
The accumulator will also protect the compressor in a system that is overcharged. True? And to what degree?
As usual, another great explanation on video. Thank you.
On a system with a fixed orifice, the accumulator would help protect the compressor from saturated refrigerant entering. Also the accumulator would help if a fixed orifice was used in a dry hot climate like Arizona since the target superheat would be off the chart during high outdoor DB temp days. In that case, a better choice is the TXV.
@@acservicetechchannel - "... off the chart ..." That's a fact!! I have to check my Goodman fixed-orifice systems late at night or very early in the morning in order to calculate a valid target superheat number. Some times of the year it's still 90-95 Degrees at 4:00 a.m. You get about a 1 hour window just before sunrise to get a superheat number. After watching your videos, I'm convinced I need to add TXVs to both units. (5 ton on the west and 4 ton on the east - Same air handlers with different orifice sizes) Thanks for all you do!!
AC Service Tech LLC. so, in all situations, a TXV will prevent saturated vapor and liquid refrigerant from getting into compressor even if the unit is overcharged. True??
For the most part a TXv will help protect the compressor since it controls superheat even in an overcharged scenario. Peter Hodgkins, the problem is that on the hot days with low indoor wb temp, the actual superheat will still be so low that it could damage the compressor. Even though the superheat is on the chart in the morning and the actual superheat is matched with the chart, the actual superheat will drop during a dry hot outdoor temp and low indoor wb temp, thanks!
got a question, watch 3 of your videos on superheat and subcooling, always wondered will those methods work on inverter ac units like the min splits, The ones at mt house ramp up and down with load and have a boost mode on most which makes it even more questionable.
The manufacturers don't tell us certain parameters in which it should work well in reference to the superheat and subcooling due to the systems ramping up and down. Unfortunetly we are stuck with only the total weight method for weighing the correct amount of refrigerant in after fixing leaks. However superheat and subcooling will still give you an idea of what is going on. High superheat when the system is running at full cooling capacity indicates a low refrigerant charge.
If you tell mini split tech support you checked the superheat they will yell at you haha. I actually got into an argument with a Mitsubishi tech support guy because I told him I had one circuit at 0 degrees superheat and one at 30. He told me to never check superheat. I told him to pound sand, it's how I know there is an issue. It had a bad EEV on circuit 2. I check it for reference. It should always be between 0 and 5. The only way to properly charge a mini split is to weigh in the total system charge. Just remember, the small pipe on a standard mini split is not a liquid line. It is a saturated vapor line. The metering device is in the condenser so you have to open the condenser up to even try to check subcooling but I wouldn't recommend it because they constantly ramp up and down (blower, condenser fan motor, and compressor) and it will be all over the place. I've had the most luck by turning all heads as low as they will go on high fan and topping off until all suction lines are at 0-5 degrees of superheat. However, if it's a blended refrigerant fractionization is a thing and it's going to leak back out anyway so that is generally a temporary fix to keep them running until a leak search can be performed.
The most important thing about mini splits is that they try to keep the evaporators as flooded as possible all the time. 0-5 degrees of superheat at the condenser with all heads set as low as possible and fans set to high. Make sure you get a compressor amp draw as well. The compressor should be pulling 2/3 to 3/4 of nameplate RLA in this scenario. If the amp draw is low you probably have inverter board issues.
@@jman0870 that’s a good point you stated. Like checking your car ac but you check amp draw to verify that your at max output on both compressors and then check your readings, I called them a while back they stated to remove all old refrigerant and recharge to factory stated lvls.
@@Kammfrank82 That's probably because it's 410a which is a blended refrigerant. Pulling the charge and weighing in fresh guarantees there is no fractionization (an improper blend essentially) and a correct charge which creates a constant to begin further troubleshooting. If you have multiple compressors it probably isn't an inverter driven unit and instead has individual circuits for each indoor unit. Inverter units typically have all the indoors manifolded together on one compressor. It doesn't really matter if it's inverter or not, all mini splits should be evaluated with the setpoint buried as low as it will go with the fan set to the highest speed. Did weighing in a fresh charge take care of your issues?
@@jman0870 yes it did, but it turned out to be a stopped up cage fan in the indoor unit. had to remove the whole front and pull the whole 4 foot cage fan out and soak and wash it. The filters on those do very little against fine dust over the 8 years I've had them.
Have you ever had issues with replacing accumulators because they start leaking refrigerant and oil out the bottom?
I just left class and we were discussing accumulators. I could not figure out how it doesn't suck liquid without liquid with a hole and bottom of the tube.. Until you said it the whole acts as a Meter in device. However what happens when the system is off?? What stops liquid from entering the hole ?
It is just surface tension vs refrigerant oil/refrigerant liquid weight. It is a very small hole. Smaller than a hole in a normal piston metering device, thanks!
Hi, is it true that heat pumps equipped with scroll compressor do not need a suction accumulator or compensator? I know they are more resistant to liquid but still, is not it a good way to prevent damage !?
I don't know who told you that but yes heat pumps usually always have an accumulator in them for several reasons including ones with a scroll compressor, thanks!
@@acservicetechchannel Thank for your anwser.. This is my supplier of ruud and reem tell me that!! I keep telling him that his compressor breaks because of that but I think he does not understand how it works.
That is very odd that they would not have an accumulator on a heat pump. The compressor will certainly have liquid entering whenever the outdoor coil freezes and that happens any time the outdoor temp is below roughly 40 degrees F because the refrigerant is below freezing the the coil starts to freeze. While the coil freezes the refrigerant is not able to superheat completely and saturated refrigerant enters the compressor. The distributor just may not understand what you are telling them unfortunately, thanks!
@@acservicetechchannel Exactly, and correct me if I'm wrong but I do not even imagine the liquid that the compressor receives every defrost when the compressor receives the liquid refrigerant of the indoor coil. I may be wrong and the high pressure refrigerant of the indoor coil returns naturally by differential pressure to the outdoor condenser but I think it could happen only if the compressor is stopped during the reversal cycle, im not sure. Thank you for your precious help and I think very soon buy your book to encourage you to continue, your channel learn me lot.
You sound exactly like the guy that does the 1aauto videos. are you a sideline mechanic also?
Ha ha nope!
Out of topic, while we re-charge liquid refrigerant to the compressor using suction line! Does it create any damage to the compressor?
Meter it in slowly. Keep your bottle on a scale and physically watch how fast you are charging. If you are scared, you can buy a sightglass to mount on your center hose and make sure it's flashing. If it goes solid back it down. Some manifolds, like Yellow Jacket Brutes, have a build in sight glass but I think Brutes are junk. The valves need rebuilt every year and they cost a small fortune. If it is a huge system or it has an accumulator it's generally not an issue at all but being safe is better than being sorry. Charging by vapor is impossible with blended refrigerants and is a massive waste of time with standard refrigerants because the bottles get so cold after a pound or two that you can't get the refrigerant out of the bottle. If you are weighing a fresh charge in always dump it in the liquid line when possible because stacking a bunch of liquid on top of the discharge valves can potentially damage them, though I've never personally seen it. Never dump a factory charge in the suction line. Bad things happen. I only charge by liquid personally.
is this book $ 49.99 or $59.99 . I want to buy on amazon but it cost more in amazon than in your website ?
Hey Ze Kenzy, yes the paperback is less expensive when it is purchased directly from us at the website at www.acservicetech.com instead of through a third party like Amazon. Shipping times are roughly the same. Amazon is a little pricey to deal with so that is why it costs $59.99 there. I can't even sell the E-book through Amazon because they would take 3/4 of the cost of the book for themselves and they would increase the E-book file size to double the original size. I am doing what I can to try to get the book out to as many techs as I can, thanks!
That book is worth every penny!
Buy it on the website. Give these guys maximum profit! I checked out with Paypal. Super easy. Thank you for the great material, videos and book. Can't wait to get mine.
Thanks a lot Peter!
I appreciate it ColdStihl!
Arent accumulators prone to leaking refrigerant?
They are thin walled like filter driers so yes over time they could rust and leak, thanks!
On vehicles that use accumulators, the steel ones are prone to leaking. Even more so because one of the automakers thought it would be a swell idea to put a foam wrapper around them to make sure that they stay nice and wet so that road salt can more effectively work it's magic and make them rust.
Some automakers use aluminum accumulators. I have never seen one of these corrode and leak. Only the steel ones. And some of the aftermarket replacements for steel accumulators are made of aluminum. An upgrade.