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A.Mortezania
01-03-2018, 09:08 PM
Dear Friends,

First of all, Thanks for participating in my questions.

Suppose that one compressor can work with R22 and R404A both of them.
As we know in same situation (Same evaporator and condenser pressure and temp.) Cp of R404A is higher than R22 and we see on catalogues that Capacity of compressor with R404A is higher than R22.

But at Maneurop (Danfoss) compressors I saw that capacity of compressor (in same evp. Temperature) at Tcondenser 30 & 40 with R404A is higher than R22 but at Tcondenser = 50C capacity of compressor with R22 is higher than R404A !

Does it have any explanation ? Why at Tcondenser = 50C this time capacity of compressor with R22 is higher than R404A ??

Sincerely yours.

Rob White
02-03-2018, 11:34 AM
.

I looked both up on a Ph chart and the only obvious difference if you plot both with a 10K superheat from the evaporator R404A is within 10K of it's critical temperature but R22 is more that 20K away from it's critical temp??

404 is a blend also and as a blend it is only as good as it's component parts, R22 being a singular pure fluid would be more stable nearer it's critical point.

Rob

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A.Mortezania
03-03-2018, 09:43 AM
.

I looked both up on a Ph chart and the only obvious difference if you plot both with a 10K superheat from the evaporator R404A is within 10K of it's critical temperature but R22 is more that 20K away from it's critical temp??

404 is a blend also and as a blend it is only as good as it's component parts, R22 being a singular pure fluid would be more stable nearer it's critical point.

Rob

.

Thanks rob. Nice and clear reason.

A.Mortezania
03-03-2018, 09:44 AM
.

I looked both up on a Ph chart and the only obvious difference if you plot both with a 10K superheat from the evaporator R404A is within 10K of it's critical temperature but R22 is more that 20K away from it's critical temp??

404 is a blend also and as a blend it is only as good as it's component parts, R22 being a singular pure fluid would be more stable nearer it's critical point.

Rob

.

Thanks rob. Nice and clear reason.