R410A in a R404A Compressor

Hi all,

I'm new in the forum so I hope to do all things corretly, if not please correct me:o

I would like to ask you the following: I have an R404A reciprocating compressor. For an application I would like to use R410A in that compressor to give it an higher refrigeration power. The evaporation temperature is -45°C and condensation temperature is maximum +40°C. I know that the discharge pressure of the R410A is higher then R404A, but limiting the operating range of the R410A at max +40°C (so more or less 23 bar), could works the compressor well? I have already checked that the compressor has an high pressure security valve that works between 28-34 bar.

Let me know about it. I know that R410A is used usually on high temperature application with more robust compressors (like scroll), but if I limit the maximum operative pressure and work at low temperature, could do an R404A compressor the job?

Thank you in advance for support.:o

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My initial reaction would be to shout NO...................

The compressor is not rated for 410 pressures and if anything goes wrong
you could have a potential pressure vessel explosion.

But if you are satisfied that the compressor is rated for the higher pressures,
your choice.

I would only add what do you know differently that the compressor manufacturers don't know?
If you though that the comp will run more efficiently, do you think the manufacturers
would have tested for it?

Just a thought but I would have thought the people who know the most about the comp
is the compressor manufacturer and they would prefer you to use it the way it was designed.

Regards

Rob

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Its bad idea.

Hi Rob and thank you for the reply.

I state that I am a newbies, I absolutely have not the knowledge that the manufacturer has.
I'm not saying that the compressor will be more efficently, but just that I could increase, with the same volumetric flow, the refrigerant effect with R410A. I think that today the R410A is used just for High temperature application in which the pressure are over 30 bar and at that pressure a normal R404A compressore can't work for sure. But what if I use it for low temp with lower pressure?

Quote:

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Originally Posted by Sawzer

Hi Rob and thank you for the reply.

I state that I am a newbies, I absolutely have not the knowledge that the manufacturer has.
I'm not saying that the compressor will be more efficently, but just that I could increase, with the same volumetric flow, the refrigerant effect with R410A. I think that today the R410A is used just for High temperature application in which the pressure are over 30 bar and at that pressure a normal R404A compressore can't work for sure. But what if I use it for low temp with lower pressure?

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410 Will find it's own pressure.

We obey basic gas laws like Dalton, Boyle and Henry's law.

If you turn off your compressor the refrigerant will expand to
a pressure that is corespondent to it's temperature.

410 at 20 degC would be at nearly 14 bar
410 at 30 degC would be at nearly 18 bar

@ 40 it would be 23 bar
@ 50 it would be 30 bar

Do you see where I'm going with this. Unless your compressor is rated for those pressures
or unless you could guarantee that the thing would never be exposed to a temperature above
40 degC, you will be beyound the working pressure and above the safe limit of the 404a compressor.

It's more about safety than efficiency.

Rob

.

.

Ignore.

Duplicate, for some reason.

Rob

.

I've cut open a few failed compressors to see what went wrong, the R410A ones have noticeably thicker steel used in there construction. I do not think it is a good idea to use the wrong refrigerant in the compressor.

Double post in some reason...

In theoretic COP - only R404A worse efficient than R410A for common HCF-refrigerant - R600a, R290, R1270, R134a, R407C is better or much better than R410A.

R410A is not suitable for high temperature application (critical temperature is low and COP going quickly down if you working near critical temperature as condensing) is why you almost never see R410A in water to water heatpump above 50-55 degree C ouput. Is almost always based on R407C (R134a in some cases) as refrigerant, and both R134a and R407C is more efficient compare to R410A if using proper design on evaporator/condenser.

R410A in Air condition on desert area (think Dubai) works bad ie. to hot on condenser side - they prefer R22 (small machine and still allowed in country) or R134a (big buildings).

R410A not fit directly for freezer room using if not using compressor with two stage compression and cooling between stage, depend make very hot head temperature and wear out compressor and oil much faster.

This works for Air/Air heat pump in Sweden ie. low temperature below -10 degree C (and 40 - 45 degree C inside condensor) is only few days per year - but every day in this condition below -10 degree C , is wear equipment for 10-20 days per days using of expected lifetime

R410A works best in +10 - -10 degree on evaporate side and 35-45 degree C on condenser side...

You have very high leak rate inside compressor under running with R410A depend high density of compressed gas and can go up to 10% of pumped mass even if have only 10 µm space clearance between mechanical part inside compressor (source Mitsubishi), and leak on this part take down possible efficient very much in thermodynamic eyes.

So, why R410A so popular ?: Promoted by refrigerant maker in many years ie. have patent on this and earn money if manufacture sitting in this glue ie. costly to redesign for new refrigerant completely from beginning.

High density HCF refrigerant make better conduct of heat (is poorer heat conduct in liquid and gas than R290/R600a/R1270 in same pressure but higher pressure compensate this) and manufacturer can cheat on evaporator and condenser design with smaller area on pipes without to much penalty of efficient - compressor can build with lower swept volume and builds cheaper etc. etc.

R410A is optimized for cheaper manufacture (and why in sell so well in manufacture lines) - not for customer efficient later. - if manufacture put same effort to optimize R290/R1270-system as on R410A - is possible going same way as refrigerator and freezer for household with R600a - is winning more or less depend showing higher efficient and lower kWh/year cost to running compare same equipment running on R134a - we talk up to 20% better efficient compare to machine running on R134a!! and R134a is best of all HCF-refrigerant in aspect of theoretical COP (theoretic difference of COP is 4% between R600a and R134a, but better heat conduct for R600a gasses itself and low pressure and low density of gas make very small leak of mass of refrigerant in used compressors and efficient for compressor is higher ).

If you live in EU or planned sell products to EU - forget new design equipment with R410A as refrigerant - this going to banned in new designed equipment sooner or later and have already penalty tax based on GWP

To days seems only have pure R32 (flammable and have very high head temperature and need liquid injection to cooling gas in compression stage or multi stage compressor with cooling of gas between stage), R152a (flammable, but very close to R134a in thermodynamic), HFO1234yf (flammable, but still very costly and very bad alternative to R134a in thermodynamic eyes) if you stick on HCF and not going line to using HC as R290, R600a, R1270 and possible RE-170 (DME) (all flamable).

All new equipment must now be designed for hold flammable refrigerant, both if using HC or using R32/R152a/HFO1234yf - all millions of manufactured and used refr

Quote:

---

Originally Posted by xxargs

In theoretic COP - only R404A worse efficient than R410A for common HCF-refrigerant - R600a, R290, R1270, R134a, R407C is better or much better than R410A.

R410A is not suitable for high temperature application (critical temperature is low and COP going quickly down if you working near critical temperature as condensing) is why you almost never see R410A in water to water heatpump above 50-55 degree C ouput. Is almost always based on R407C (R134a in some cases) as refrigerant, and both R134a and R407C is more efficient compare to R410A if using proper design on evaporator/condenser.

R410A in Air condition on desert area (think Dubai) works bad ie. to hot on condenser side - they prefer R22 (small machine and still allowed in country) or R134a (big buildings).

R410A not fit directly for freezer room using if not using compressor with two stage compression and cooling between stage, depend make very hot head temperature and wear out compressor and oil much faster.

This works for Air/Air heat pump in Sweden ie. low temperature below -10 degree C (and 40 - 45 degree C inside condensor) is only few days per year - but every day in this condition below -10 degree C , is wear equipment for 10-20 days per days using of expected lifetime

R410A works best in +10 - -10 degree on evaporate side and 35-45 degree C on condenser side...

You have very high leak rate inside compressor under running with R410A depend high density of compressed gas and can go up to 10% of pumped mass even if have only 10 µm space clearance between mechanical part inside compressor (source Mitsubishi), and leak on this part take down possible efficient very much in thermodynamic eyes.

So, why R410A so popular ?: Promoted by refrigerant maker in many years ie. have patent on this and earn money if manufacture sitting in this glue ie. costly to redesign for new refrigerant completely from beginning.

High density HCF refrigerant make better conduct of heat (is poorer heat conduct in liquid and gas than R290/R600a/R1270 in same pressure but higher pressure compensate this) and manufacturer can cheat on evaporator and condenser design with smaller area on pipes without to much penalty of efficient - compressor can build with lower swept volume and builds cheaper etc. etc.

R410A is optimized for cheaper manufacture (and why in sell so well in manufacture lines) - not for customer efficient later. - if manufacture put same effort to optimize R290/R1270-system as on R410A - is possible going same way as refrigerator and freezer for household with R600a - is winning more or less depend showing higher efficient and lower kWh/year cost to running compare same equipment running on R134a - we talk up to 20% better efficient compare to machine running on R134a!! and R134a is best of all HCF-refrigerant in aspect of theoretical COP (theoretic difference of COP is 4% between R600a and R134a, but better heat conduct for R600a gasses itself and low pressure and low density of gas make very small leak of mass of refrigerant in used compressors and efficient for compressor is higher ).

If you live in EU or planned sell products to EU - forget new design equipment with R410A as refrigerant - this going to banned in new designed equipment sooner or later and have already penalty tax based on GWP

To days seems only have pure R32 (flammable and have very high head temperature and need liquid injection to cooling gas in compression stage or multi stage compressor with cooling of gas between stage), R152a (flammable, but very close to R134a in thermodynamic), HFO1234yf (flammable, but still very costly and very bad alternative to R134a in thermodynamic eyes) if you stick on HCF and not going line to using HC as R290, R600a, R1270 and possible RE-170 (DME) (all flamable).

All new equipment must now be designed for hold flammable refrigerant, both if using HC or using R32/R152a/HFO1234yf - all millions of manufactured and used refr

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In Dubai, manufactures with using R410a is positing their unit will make high cop, and energy efficient. Ex: daikin. Highest ambient temperature in Dubai is reaching some time above 50c.as you say, there is not any truth in performance???:confused:

If we assume 70 degree C as condenser temperature as >50 degree C hot day on the roof and try in coolpack with standard value on starting of program except temperature adjusted to +10 degree C on evaporator side and 70 degree C on condenser side.

cooling COP with:
R12 = 2.258 head temperature 92.7 degree C
R134a = 2.135 head temperature 89.3 degree C
R22 = 2.177 head temperature 112.5 degree C
R290 = 2.075 head temperature 86.1 degree C
R404 = 1.421 head temperature 89.7 degree C
R407C = 1.875 head temperature 104.9 degree C
R410A = 1.576 head temperature 107.7 degree C

If we using suction gas exchange with liquid line after condenser for R290 and accept 107 degree C head temperature (same as R410A in this situation) with thermal efficient of 0.43 in heat exchange, cooling COP with R290 going up to 2.212 or in same range as between R12 and R22.

R410A = 1.576, R290 with exchanger = 2.212 - is quite big difference in possible cooling efficient for same amount of electricity...


If we assume 'only' 60 degree C condensing temperature...

cooling COP with:
R12 = 2.951 head temperature 80.9 degree C
R134a = 2.844 head temperature 78 degree C
R22 = 2.863 head temperature 97.9 degree C
R290 = 2.782 head temperature 75.3 degree C
R404 = 2.281 head temperature 77.7 degree C
R407C = 2.614 head temperature 90.7 degree C
R410A = 2.431 head temperature 93.3 degree C

If we using suction gas exchange with liquid line after condenser for R290 and accept 93.3 degree C head temperature (same as R410A in this situation) with termal efficient of 0.45 in heat exchange, cooling COP with R290 going up to 2.889 or in same range as between R12 and R22.

No wonder why people try to stick with R22 if possible even if head temperature is quite high.

R290 is very promising on high efficient but need new thinking in design do hold low charge and flammable refrigerant - but now future allowed refrigerant in EU with R32/R152/hfo1234yf etc. manufacture forced to working with and designing for flammable refrigerant even here.

If electrical price is high. COP is important and low head temperature is important if you want longevity of equipment.

Practical COP is very depend how well designed equipment are and bad designed equipment with R12 as refrigerant can give lower efficient than well build R410A equipment in case of 70 degree on condenser, but if make same effort in design on respective refrigerant - R410 is not best choice in term of best possible COP.