For A/C, are R290-based refrigerants more efficient than R22?
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For A/C, are R290-based refrigerants more efficient than R22?
This may Not be the reply you are after but its also something i have been playing with
Look Up www hychill com au /tech
Sorry no dots on the URL
as I can not post URLs As yet..Must have 15 post or more :(
Anyway then look up Presure temp charts
They have got a product called HR22/502 Hydrocarbon replacment for R22
Other Interesting Claims As well
Yes he all ready started a thread for that but got not many answerer's. Problem is we know people will pile any BS on if it will sell their product, the thing is with a good high quality HC blend no BS or hype is needed to sell it. Star, there is no simple answer I have read through insurmountable PDFs comparing performance to heat moved and yadda yadda,,,,,, PDFs and so far R-22 and HC are dead on par to each other with HCs taking the lead in being gentler on the compressor, but it is best to use a thicker oil, but for a sealed A/C chances are it will die of other issues long be for Bering wear!
I would recommend getting the R22a as it is refrigerant grade Hydrocarbon and thus will work much better then BBQ tank propane, and it is dirt cheap per can (Well at least compared to R-22 on the Canadian market, that and it is nearing its end of life date!) I have an A/C here that I intend to do some messing with, I want to get a can of the R-22a and compare it to standard BBQ Tank propane and R-502, so become a pioneer like my self and just do some R&D for the community, either way I see it as more then worth while to invest in it and give it a fair try!
Ignore the ones who whine about ZOMFG its teh flammables, or bs like that as I will be throughly impressed by ANY one who can manage even a puff from a leak! Just follow good repair practises, and ensure all the electrical is in good health and there will be no issue. And remember you need much less HC then you did R-22.
R290 is definitely a competitor against most HCFC and HFCs. Many studies of the IIR show that systems especially devised for R290 have a better COP and a lower TCO.
The refrigerant charge must be compared against the safety rules, though. In EU, A/C must not have more the 3Kgs of any flammable refrigerant and in the event of a total release of refrigerant, the resulting mixture with air should not exceed 20% of the lower flammability limit (LFLM). In the case of R290, LFLM is 38 g/m3
I would not recommend making blanket statements like this as sooner or later some idiot will say the same thing and blow himself up.Quote:
Originally Posted by The MG Pony
You have to be aware of the flammable nature and deal with it according to the safety regulations. Saying not to worry about it only tells an uninformed person; don't worry, be happy, be ignorant, what you don't know can't hurt you.
This is about the same thing as saying the HFC's CFC's, etc. are safe. They will kill you quickly if vented in closed spaces.
A cavalier approach to refrigerant use is upsetting to say the least.:(
I am aiming more at the ones who greatly over exaggerate the dangers, I am by all means strict on knowing about the dangers and I am all so greatly against thoughs who greatly exaggerate to promote fear and miss understanding. I didn't want to go so far in depth as to what I meant by that but appears that I needed too.
BTY My trade mark signature is: Ignorance is not bliss, you may not know a semi is going to hit you but you'll be road kill any way!
IE Learn as much about the environment around you and how and why are the best questions one can ask.
If you go to www.EXtemeSystems.com you will find one who seems to grossly over exaggerate the risks, to me this is as much a dis-service then not teaching them at all. Fear is more dangerous then ignorance!
Is the use of a crankcase heater more important with R290?
That I can live with. We see a lot of this with ammonia systems. Unfortunately, most of the hysterics come from ***** guys. Hydrocarbons would also fall into the category of panic attacks for some. If someone knows it is flammable he/she is a lot more likely to treat it with care.Quote:
Originally Posted by The MG Pony
The bottom line is, understand the dangers and the refrigerant behavior and you will live to a ripe old age.:D
Along the same train of thought. Peter and I recently had the opportunity to collaborate on a project in South Africa with another gentleman.
There was an investigation into a hermetic compressor that exploded (literally!). The refrigerant was R-22. Not overcharged, torches were not involved but the compressor exploded. Our best idea was the R-22 and air mixture reached the proper percentage to detonate. Refrigerants do some strange things.:rolleyes:
Thats what I try and explain to the ***** guys, Doesn't matter if the bottle says non flammable! Once it is mixed with oil ALL refrigerants are flammable or the oil is or both!
So the ones that jump up and down screaming about hydrocarbons flammability are being hypocritical unintentionally, flammability to a point is moot. It is the type that make the system sound as if it will go supernova from the slightest leak that drive me insane!
Respect and under standing YES! Fear mongering and ignorance NO!
Along the same train of thought. Peter and I recently had the opportunity to collaborate on a project in South Africa with another gentleman.
There was an investigation into a hermetic compressor that exploded (literally!). The refrigerant was R-22. Not overcharged, torches were not involved but the compressor exploded. Our best idea was the R-22 and air mixture reached the proper percentage to detonate. Refrigerants do some strange things.:rolleyes:[/quote]
Any info on this case Somthimg that would interest me very much..
You can go directly to Mr. Alders website and read the report. This should be quite an eye-opener.:cool:
http://www.alder.co.za/blowup.htm
Cowboys is what we call them here !!Quote:
Originally Posted by US Iceman
& there world wide not just in this Country
Very Interesting read .. :)
here we call em trailer park engineers, or wannabes
Nothing against Cowboys :)Quote:
Originally Posted by The MG Pony
Its just a saying!!!
Theres anothing saying we have her
**** Happens!!
But My old man used to say
**** dont happen A-holes cause It..
& in this case There seemed to be a abundant amount of them..
I like your fathers saying :)
Yeah well, this is what happens when people do not receive sufficient training and they are thrown to the wolves to fend for themselves.
People get hurt or killed because of this.
There are many stories of people getting killed because they worked on something they did not understand.
The refrigerant used is only part of the problem. A person needs to have adequate training, sufficient tools, and oh yes don't forget...some experience gained under a mentor.
Too many people think this business is the way to a fast bit of money, and others think "if I pay the least amount I can for service I save money".
A lot of people have either been very lucky, or, their story has not been made public.:(
R290 is an excellent alternate to R22. They are pretty comperable in net capacity and efficiency. To see the exact difference, you will need to run selections and balance a system for both refrigerants.
R290 is used mostly in refinery or chemical plants as they often have propane in the plant. Some issues to deal with on Propane are:
explosive ....the refigeration sytem usually needs to be designed to Class 1, Group D, Division 2, NEMA 7 area classification.
Often the customer specifications will require the compressor casing and ALL vlaves be carbon steel bodies. Some compressors are not available in carbon steel, only cast iron.
Pressure safety valves may need to be carbon steel. Plant may not all you to size per ANSI/ASHRAE 15 and use the ASME Fire Sizing procedures.
Oil....oil dilution is a problem and you need to be assured the compressor suction is dry and the oil is kept warm. Most often we use a poly glycol based oil with hydrocarbon refrigerants.
R290 does not superheat much when it is compressed, so you need to watch discharge temperatures on oil injected screw compresors.
In additon to R290 (propane), propylene, ethane and butane are sometimes used for specific applications.
Ken
Piping may need to be ANSI B31.3, not ANSI B31.5.
My Dad did not have an engineering degree, but he had more practical knowledge than a lot of degreed engineers I know. He called them "arm-chair engineers" and he ran a few of them out of his shop.Quote:
Originally Posted by The MG Pony
Ken
My grandfather was the same. After someone had been doing the same job for over 50 years successfully they have to be pretty sharp with all of that experience.Quote:
Originally Posted by TXiceman
Quote:
Originally Posted by TXiceman
Hi Any chance if expaining this statement More??
Is that much of an issue with scroll compressors?Quote:
R290 does not superheat much when it is compressed, so you need to watch discharge temperatures on oil injected screw compresors.
Thats when you call them dam good techs, To me paper means nothing, it is what you know that determines your ability, for some reason every one thinks it is paper first knowledge second now days.Quote:
Originally Posted by TXiceman
Trailer park engineer is what we call one with no skill, no clue, and good chance of no brain when he decides that he knows enough to to manage to bodge it together just well enough it looks like it works. You all can guess what the end result is!
Take out a P-H diagram for propane and look at the constant entropy compression lines. Follow up from an ET to a CT and then do the same on R22 or R717.Quote:
Originally Posted by Makanic
In a screw compressor, yo are mixing oil in with the compression and the oil is used to seal the rotors plus remove part of the heat of compression. The actual discharge temperature will be to the left of the constant entropy instead of the right as in a recip compressor.
In a larger industrial twin rotor oil injected machine, ther is an oil cooler to cool the oil. Typically with a screw operating on propane, the oil cooling load drops when you unload the compressor. Since the oil cooler surface is fied,it has a tendency to lower the oil temperature and discharge temperature. This does not hold true with most R22 or R717 compressors.
In the case of propane, you need to keep the discharge saturation about 20 dF above the CT. So if you have a SCT of 100 dF you want the discharge and oil temp above 120 dF. Much closer and you start to run the risk of condensing in the compressor during compression which dilutes the oil and will ruin a compressor due to loss of lubricity of the oil. The compressor will still show it has good "oil" pressure when it may be 1/2 propane.
In a lot of propane systems, we may add a liquid/suction exchanger to put some heat into the suction and get the discharge temp up. Butane is a really bad actor in screws and I generally want 20 to 40 dF suction superheat to keep the discharge warm enough. Same goes for R134a.
As for the blends using propane and butane, you need to be really careful to keep the compressor oil sump warm in colder weather or you will wind up with a sump half full of propane and oil mixed.
I do not have a problem using a propane blended refrigerant in a scroll, but I sure would not use pure propane...my personal choice.
If you want to discuss this more, drop me a PM with your phone or email address.
Ken
The information TXixeman is discussing is very important and something you need to watch out for. R-114 used to be terrible about this. If the gas cooled off enough it could start to condense during compression.
The simple fact is; if the constant entropy lines are steep and close to the dew point curve you have to add a lot of suction superheat. This translates into an increase in discharge temperature and helps to keep this from happening.
If the constant entropy lines extend off to the right a good distance (like ammonia) the problem becomes much less important unless some other factor comes into play.
Thank you very much for spending the time & your effort in explaining this futher.. Very Interesting factsQuote:
Originally Posted by TXiceman
If I retrofit a R22 system to R290 (blend), how much would the efficiency change?
You can't. EEx components must be used.Quote:
Originally Posted by star882
Nonickname: He's going to be charging a small window A/C with R-22a which from what I can tell there is no specification saying he can't, from what I have read any way which is not too much. The waters on Canadian law regarding same thing is rather murky as well!
There are some R290-based mixtures designed as a virtually drop-in replacement for R22. Not all R290, of course, but they do work in R22 systems. At least one of those (Enviro-Safe 22a) even guarantees that it will not damage equipment when used correctly.Quote:
You can't. EEx components must be used.
Close, but replace "he" with "she", "window A/C" with "split system", and "R-22a" with "Enviro-Safe 22a" and you have it.Quote:
Nonickname: He's going to be charging a small window A/C with R-22a which from what I can tell there is no specification saying he can't, from what I have read any way which is not too much. The waters on Canadian law regarding same thing is rather murky as well!
Ah K, then with some thing that large I'm not sure if you will be allowed as thats may exceed the limit.
The system's original charge is 145oz. According to Enviro-Safe, that means I would only need about 58oz of 22a.
Must be one hell of a small split!
Ooooh.... what an equipment :-)
kind of funny I ran across this thread.. thought I would re-incarnate a dead thread just for the pure purpose of noting that I ran a 2 ton scroll split system on envirosafe-22a for 3 years with no ill effects noted.. my superheat and sub-cooling was a little better than with R-22.
EXCEPT when I was under super heavy cooling condiotions.. ambient outdoor temp above 100 degrees F.. then it seemed worse performance-wise than the R-22 was....
just an FYI and yes I know its an OLD thread.. just thought id comment because HC refrigerants are very much in play right now..
-Christopher
The answers here are great. Maybe I'm missing something but there are a couple of items I don't see mentioned.Quote:
Originally Posted by The MG Pony
Using Propane, "R-290" has one minor problem not talked about here unless I just missed it.
Also I don't see it's major advantage either.
1. The bad.... the stuff you get for your cooking has a good deal of moisture in it.
2. The Good....R-290 is a uni-molecule.
The good is a uni-molecule has several unique properties making it a little superior to the complex R-22 molecule for use in refrigeration systems.
Look it up, this isn't the place chemistry lessons.
I've run tests with a system on R-22 and measured cooling against power consumption with both in the same system.
With R-290 I consistently show about a 18% energy saving with slightly better cooling. Using the lower power consumpton and slightly cooler air might substantiate Envirosafe's claim of 22% energy savings.
That is their claim and I'm not going to go attempt to prove or disprove it. The stuff works and saves me a bundle.
No! I never use the stuff in a Customers system.
Can't you just see the law suit if someone found out it was there?
I use R-290 all the time but I made a charging manifold with series of two driers.
As we all know, moisture is a problem with 22 as well.
Some things are good when all wet but not refrigeration.
Just as a precaution, I also have a recovery tank I have filled with R-290 using gravity and my dryers.
Keeps people from asking stupid questions about the Propane tank sitting around with refrigeration gauges on it!
One ugly issue with Propane/R-290 is Mercaptan.
You know the stink in it. If you can get around the stink, it's great stuff! Somewhere I've heard that before.
It is Sulfur based.
In the presence of moisture Mercaptan will make Sulfuric Acid. So be sure your system has a good dryer installed and to use a drier when servicing.
The system on my house has been running on R-290 for over 12 years. It has never had R-22 in it.
It runs quiet and does a very good job!
Just as a side note. Blends of R-22 and R-290 are no problem.
Maybe slightly less efficient than straight R-290 but that is the only problem I can see.
A good rule of thumb for servicing with straight R-290 is to service a running and stabilized system to a low side pressure of about 80PSI. Of course you guys know about proper pressure and temperatures don't you?
If it's dry, no problem.
Well....... dry has it's place but wet can be great huh guys?
I found a photo of Obama in deep, deep thought.
I know this is an old thread but since I have been using HC blends in my cars for 10 years it caught my attention.
Something that bothered me in this thread is she asked a question which was answered then it seems like it became a soapbox discussion and people even stopped answering her questions! She asked about a crankcase heater which was ignored.
I'm not trying to be a jerk but I think people were wrong to hijack her thread to make a point! Okay, that said I will get off my soapbox.. LOL!
By the way ChillGirl, I love your Obama photo, so true!
Thanks TXiceman for that excelent explainsion ,we have saying here (who older than u by 1 day , has more experience than u by 1 day)Quote:
Originally Posted by TXiceman
BBQ Propane works a treat!