R410a Good or Bad in hot climates?

[Grizzly]

Having read the below I am beginning to understand why R410a may not be so good in the hotter Countries!




Critical Point Consideration
Consider R-410A, a front runner to
replace R-22 in many applications. It
has a critical point of 158.4°F as
compared to R-22’s critical temperature
of 204.8°F. Where this is an issue is in
air-cooled products in high ambient
locations such as the U.S. south west.
Here the design ambient condition is
often 105°F or higher. Add to this a
25°F refrigerant approach and now R-
410A is only 28°F from its critical
point. R-410A is being pushed to the
top of its “dome” leaving very little
room for condensation. The result is
reduced efficiency. It is not unusual for
a 5 ton R-410A condensing unit at ARI
conditions to be reduced to only a 3 ½
ton condensing unit in high ambient
areas.
Grizzly

[marc5180]

Hot climates:eek: i wish!!

[US Iceman]

This is one of those refrigerants where you have to change how you design systems or how they are applied. In the text provided Grizzly it mentions 105°F ambient temperature + 25° TD for the air-cooled condenser. My question is; who in their right mind would design a system for 130°F condensing temperature in today's market?

Even with 105°F ambient dry bulb temperature, the condensing could occur via an evaporative condenser using the normally much lower wet bulb temperature.

It's not the refrigerant which makes this an inefficient operation, it's the use of 130°F condensing temperature!

The old design assumptions are no longer valid with the energy costs of today and the refrigerants that were forced upon us.

[Marc O'Brien]

The result is
reduced efficiency. It is not unusual for
a 5 ton R-410A condensing unit at ARI
conditions to be reduced to only a 3 ½
ton condensing unit in high ambient
areas.
Grizzly


Working on enthalpies alone, between R410A and R22, assuming similar system design efficiencies, it seems R410A might lose just less that half again as much capacity as does R22. So if, in a rising ambient, R22 lost 9% then R410A would lose perhaps 14%.

[K.R.Iyer]

I have this intereting piece of study of R22 Vs R410A at high ambient for you to see. The pdf file size is 220KB, which is bigger than the 100KB allowed. HOw could I upload?

[superswill]

I have this intereting piece of study of R22 Vs R410A at high ambient for you to see. The pdf file size is 220KB, which is bigger than the 100KB allowed. HOw could I upload?


try using

https://www.yousendit.com/

[dan wong]

I am in Phoenix, Arizona. its about as hot as you can get. R410 seem to work ok here.

I am wondering; does the rest of the world use the same refrigerant as we do in the U.S.A. Does the British use the same refrigeratant as the German as Japanese, or Chinese, or Assie ? Or do they use different blend - more suitable for regional climate?

[compresspec]

I am in Phoenix, Arizona. its about as hot as you can get. R410 seem to work ok here.

I am wondering; does the rest of the world use the same refrigerant as we do in the U.S.A. Does the British use the same refrigeratant as the German as Japanese, or Chinese, or Assie ? Or do they use different blend - more suitable for regional climate?

I am a compressor guy. From this point of view if we regard HFC refrigerants for the future there are various trends in the world. R22 will be banned (in Europe it still is) in various steps. Since in Asia and China the ban will come 2030 or 2040, what is really a long term horizont. Consequencly R22 is still common in wide application fields.

As alternative refrigerants can be seen R134a for centrifugal and screw compressors in A/C. In smaller capacities (scrolls and recips) the trend seems to go towards R410A. In commercial refrigeration the alternate HFC seems to be R404A (sometimes R507A). In Germany and some other European countries also CO2 it popular in commercial refrigeration in some areas and applications.

Greets from good old Europe

[compresspec]

Especially due to the high pressure (and also some other reasons) with R410A the condensing temperature on the upper end is restricted.

I think a good information give the refrigerant report from Bitzer: <SORRY I am not allowed to post an link, before I made 15 posts. A PDF as attachment will be larger than the 100 kB border>
For information please copy the following line in your Web-browser and remode the under-line slash in the link: w_ww.bitzer.de/download/download.php?P=/doc/&N=a-501-15.pdf&ccode=DE

Hopefully it works in this way!
For R410A versus R22 please see page 21 ff. ;)

Regards!

[NoNickName]

We are not particularly fond of R410a on this side of the pond. It is mainly found in precharged split systems and the like, but no commercial refrigeration is done with R410a.
Pressures are not a problem, but efficiency is. R410a is not efficient enough to be considered a viable option.

[tarcau mihai]

I've been work on chiller screw compressor R410a Q=5300 kw,condenser water cooled in Carribean sea...in which category can be putted this???????
And i have a doubt ,if you have a leakage of 20% of a 1400kg of R410a can you just refill with a new 280 kg of R410a ??????????????
Regards Mihai.

[PaulZ]

A lot of the split a/c's in Aust are R401 and seem to work ok, or at least the ones we deal with.
Can't say I have seen a lot of R410 in commercial / industrial. The new ones we come across are R404A, R407C and R507.
Paul

[TXiceman]

I am not particularly fond of any of the 400 series refrigerants and as far as I can tell, no one has come up with a comperable replacement for R-22.

Ken

[Sridhar1312]

Yes working pressure of 500+psi is cause for concern as many of the split refrigerant piping is done by people at site and pressure tested.Chances are leaks are possible causing perenial problem of leak

[Slatts]

I am wondering; does the rest of the world use the same refrigerant as we do in the U.S.A. Does the British use the same refrigeratant as the German as Japanese, or Chinese, or Assie ? Or do they use different blend - more suitable for regional climate?
Hi Dan. That's Ausie mate.:off topic:
And yes the same refrigerants are used all over the world.
As PaulZ said, we see more and more splits using R410a over here. I'd like to hear from any fridgies in Victoria who've been having 40C plus (104F +) weather lately about how the 410 systems are handling it.

[dan wong]

Hot climates:eek: i wish!!
Hehe, In Phoenix, Arizona, Ambient temperature often exceed 115F. (summer). Roof top temperature close to 140F. Can not stand on roof long. Now try to change out that compressor !!.:rolleyes:

[rude]

Hi Dan. That's Ausie mate.:off topic:
And yes the same refrigerants are used all over the world.
As PaulZ said, we see more and more splits using R410a over here. I'd like to hear from any fridgies in Victoria who've been having 40C plus (104F +) weather lately about how the 410 systems are handling it.
im not in melbourne but i can vouch 410a units work fine in the 40 degree heat. Only problem is dodgy installers not doing their flare connections properly and small amount of gas leaks dont help the units perform to well.