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Lc_shi
08-02-2006, 08:57 AM
R22 system can be switched to R407C and R134a only with changing the lubriant oil to POE.
R410a system need redesign for r410a has higher pressure and more capacity.
our boss list the refrigerant substitute issue on this year work task for R&D.
who has the experience could tell me more about it?thx

regards
LC:confused: :)

afeef
08-02-2006, 10:54 AM
dear
the replacements of refrigerants is stated in this link
www.harpintl.com/guide.htm

thanks
yours/afeef:rolleyes:

Johnny Rod
08-02-2006, 11:33 AM
There are quite a few chioces for R22 drop-ins, check out also the Isceon range (Du Pont) and the RS range (RefSols)

http://refrigerants.dupont.com/

http://www.refsols.com/

Many of these don't need an oil change as they work with mineral oil (check the details obviously).

If you can use a hydrocarbon, there is also Care 30 which has pressure similar to R12 but is flammable.

Peter_1
08-02-2006, 07:44 PM
Lichuan,

Think you have to think about tube thickness for the whole system, you have to meet the PED requirements if you wanna export to the EU, ...

Special designed compressor, different HP and LP settings, ...

Furtehrmore, i don't see any difference between R410a and any other gas.

chillin out
08-02-2006, 11:23 PM
R410a system need redesign for r410a has higher pressure and more capacity.
Not true, R410a can reuse the same pipework as any other air con unit. That is the beauty of using R410.

So long as you pressure test it properly it will be ok.


Chillin:) :)

Lc_shi
09-02-2006, 02:46 AM
Not true, R410a can reuse the same pipework as any other air con unit. That is the beauty of using R410.

So long as you pressure test it properly it will be ok

it's a good news ,but how the performance will be?:) :confused:

Peter_1
09-02-2006, 07:10 AM
Not true, R410a can reuse the same pipework as any other air con unit. That is the beauty of using R410.
So long as you pressure test it properly it will be ok.
Chillin:) :)

I was thinking in general because LC's question didn't mention that he was talking about AC.
Try same 3 1/8 pipes once on R22 and R410a with PED regulations what will saa..pressure testit properly :eek:
I doubt it will work

Rob S
09-02-2006, 07:24 AM
You can not use 410A with copeland semi-hermetics. The cast cases are only good up to 650psig. Granted 410A will only get to those pressures with out condensor cooling.
Line sizing for 410A is smaller. And compression ratio is usually bit lower in AC.

fridg
09-02-2006, 07:50 AM
Not true, R410a can reuse the same pipework as any other air con unit. That is the beauty of using R410.

So long as you pressure test it properly it will be ok.


Chillin:) :)

I have been told by a few tradies at Heatcraft
(not brand bashing)
that 1/4 " is fine to use 3/8 " maybe
but the anything up from this will have to be replaced

How did you come to this conclusion Chillin , is
this from experience ?

And if so is this only applicable to ac units ?

LanzaCarlos
09-02-2006, 08:32 AM
Why is Isocon 59 (R417A) not being considered as all the reviews I have read suggest that it is not only does it "Drop-In" but it also gives superior performance?

chillin out
09-02-2006, 10:46 PM
And if so is this only applicable to ac units ?
I know it is true for ac units, I don`t know about fridge units.


How did you come to this conclusion Chillin , is
this from experience ?
http://www.modbs.co.uk/news/fullstory.php/aid/198/New_refrigerant_in_old_pipes.html

Plus I was told this at a Mitsubishi training course.

Chillin:) :)

chillin out
09-02-2006, 10:49 PM
Just to add...

R410a is designed for ac only..

http://www.refrigerants.com/hfc-r410a.htm

Do people use this gas for fridges?

Chillin:) :)

fridg
10-02-2006, 06:51 AM
Just to add...

R410a is designed for ac only..

http://www.refrigerants.com/hfc-r410a.htm

Do people use this gas for fridges?

Chillin:) :)

Thanks for the reply and thanks for the heads up on
the retro fit for R410 ac units

As for using R410 in fridges , i have not heard of this
but if we use R22 in medium temp applications
and R22 is fazed out , well we might use R410 as a
replacement.

Just dont let the home owner try and fix the thing with
the pressures involved.

Vymeniky
12-02-2006, 10:39 AM
Hello,

for our new generation of swimming pool heat pumps, we need to switch over to the new refrigerant R410A, which means we need a pressure rating on the refrigerant side at least 32 bar (450 psig?).

At the same moment we need to use salted pool water on the secondary side.

Can you deliver any condenser 32 bar, 9 kW capable of handling salted water? (Cu/Ni, titanium coaxial possibly)

Attached please find the calculation of a (plate) condenser that we need to replace by your unit.

Awaiting you response, hopefuly technical and price quotataion

sincerely

Martin Pekarek
info@vymeniky.cz






Not true, R410a can reuse the same pipework as any other air con unit. That is the beauty of using R410.

So long as you pressure test it properly it will be ok.


Chillin:) :)

US Iceman
13-02-2006, 12:49 AM
R410a is designed for ac only..

And why is this???

Since R-410a has a higher vapor pressure than R-22, I suspect it could be used for low-temperature refrigeration without any problem. I have looked at some R-410a refrigeration applications and can't see any reason why it could not be used. OK, air-cooled condensing is one problem due to the high pressures...

I have to agree with Peter on the pipe pressure ratings. This should be verified by calculation for the intended operating pressure. When someone says it will work for one application, you should not accept the fact that it could work for all. These kinds of statements will get someone hurt.

If you are trying to evaluate refrigerants try this...

Calculate the mass flow requirements for the capacity needed at the operating conditions. Then convert the mass flow into suction volume flow (mass flow X specific volume of suction gas.

The lower the mass and volume flow will be (for a given cooling load) shows the impact of the refrigerant being used.

What you are trying to find is the highest amount of heat absorption capability per cubic meter of vapor. Another method is to calculate the net refrigeration effect (NRE) for the cycle. Then multiply the NRE X the gas density at the evaporation temperature.

I believe this is one of the problems of all of the new refrigerants. We have about 70 years of history, expectations and experience with the old refrigerants, that we are now using to design new systems with.

Lc_shi
13-02-2006, 02:25 AM
I agree Iceman's idea.
But I've not seen r410a application in low temp field. May there are some issues to consider?

chillin out
13-02-2006, 07:58 PM
Hi USiceman,

What I have said in my previous posts is only what I have been told and found on the net.


We have about 70 years of history, expectations and experience with the old refrigerants, that we are now using to design new systems with.
Is this good?

Or is it time to forget the past and reinvent the wheel?

Chemistry has come a long way in 70 years, They probably laugh at the primative gases we used to use.

Sizing up pipe work is differant for this gas, you can get away with using smaller pipes if need be because the pressure would force through.

I think I was told that, if the original pipes for R22 system is being used and there is a problem with sizes, then you can oversize the cond unit.

This is really useful.

Lets say for instance you had to reinstall an air con unit, and the pipe run goes above (or through) a 'clean' room. Then using existing pipes will enable work to carry on in the 'clean' room and no need to spend 2 days cleaning up plus it will save a lot of money and time on installing.


Chillin:) :)

US Iceman
13-02-2006, 08:36 PM
Is this good?

Or is it time to forget the past and reinvent the wheel?

I don't think we need to reinvent the wheel as you described it. I do however think there are a lot of "rules-of-thumb" that have been developed with the older refrigerants. These may not apply to the new refrigerants.

I believe we need to be very careful in evaluating the piping for the maximum allowed pressure rating and pressure loss. Compounding this is the effect of the temperature glide with some of the refrigerants.

The new refrigerants do not behave the same way as our old favorites (R-12. R-22, R-502, etc.). No glide and nothing special on the copper tubing (Type K or Type L ACR copper) and fittings.


...you can get away with using smaller pipes if need be because the pressure would force through.

Yes, but if the pressure drop increases in the pipe the suction pressure could be lower, which can effect the compressor capacity.

I guess what I'm saying is that we should be evaluating the pipe and the system for the desired operating conditions with the new refrigerants.


I think I was told that, if the original pipes for R22 system is being used and there is a problem with sizes, then you can oversize the cond unit.

This confirms what I'm trying to describe. Instead of replacing the pipes to meet the requirements, install a bigger condensing unit. This sounds like something a manufacturer would have said. "Buy my bigger unit, instead of the smaller one."

I understand what you are saying about the additional cost to install the new piping. In fact, the slightly larger unit could be more cost effective in this case.

My concern is that someone installing a new system will read something like this and say, it is OK to use smaller pipes, without understanding what is going on.

This goes back to my earlier comment about 70 years worth of history. Many rules-of-thumb have been developed for many different circumstances with the old refrigerants.

With the new refrigerants, some of the rules-of-thumb may not apply. More importantly, someone may not understand why they don't apply.

I would really question the use of R-410a for a heat pump though.

Rob S
14-02-2006, 04:22 AM
I would really question the use of R-410a for a heat pump though.

Are you saying you wouldn't use 410A for a heatpump? Refrigerant vs Refrigerant 410A beats 22 hands down.

glabah
02-03-2006, 05:12 PM
Why is Isocon 59 (R417A) not being considered as all the reviews I have read suggest that it is not only does it "Drop-In" but it also gives superior performance?


It depends a lot on the application. R-417A is intended for air conditioning applications due to the pressures and temperatures involved and the characteristics of the refrigerant. There are other replacements for refrigeration and others for even lower temperature evaporators which perform better at those temperatures and pressures. There is no single drop-in replacement for R-22 that performs best in all former R-22 applications.

Also, it must be remembered that R-417A was developed in the UK by Rhodia. Those of us here in North America were subjected to a whole bunch of anti-R-417A propaganda by DuPont, which somehow magically disappeared off of DuPont's web site when DuPont purchased Rhodia's R-417A production capacity.

The problem I see with R-410A has to do with where the critical point is located. It is only about 160 deg. F, vs. over 200 deg F for R-22, and for our company that might be a problem in certain applications due to high ambient temperatures. R-417A apears to be a little less of a problem because the critical point there is only slightly less than R-22. However, we have yet to actually construct a system with R-417A in it.

old gas bottle
02-03-2006, 09:21 PM
we are looking into R22 alternatives too,some suite differant applications better than others, the other thing is which one will win the race and be arround for a few years,i dont like the idea of retrofitting with R410, for a start the extra pressure in a system will sooner or later cause problems,apart from the smaller design pipe sizes its also a better rated copper to stand it,what about solinoids etc and also it should only go in hermetic systems, access fitting sizes too that are fitted to R410,alert you to the higher pressure.

old gas bottle
02-03-2006, 09:24 PM
errrrrrrrrrrr,missed a few pages,oooop,s sorry chaps.

Camille
02-03-2006, 09:47 PM
where exactly do you have to click to
post new messages

thanks in advance

Camille

Toosh
02-03-2006, 10:02 PM
Hi Camille At the top of the page there are two menu bars new posts is on the bottom one

Regards Toosh

chillin out
02-03-2006, 10:13 PM
Click the link at the top of the page

http://www.refrigeration-engineer.com/forums/index.php

Then goto the index that most suits your need.

Then click "new thread"

follow instructions from there.

Chillin:) :)