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Comparing efficiency of R12 and R134a with properties ?

Comparing efficiency of R12 and R134a with properties ?

Comparing efficiency of R12 and R134a with properties ?

(OP)
Hi Guys.

It's for a long time been mentioned or thrown around that R134a is Less efficient than R12, however
technical bulletins from such as compressor manufacturers say otherwise that R134a is more efficient.

From comparing properties, I can see that R134a appears to have a greater refrigerating affect on paper.

The one that to me would show is that R134a has a decently higher latent heat of evaporation, which would mean
that for the same given quantity of R134a and R12 liquid, R134a can absorb more energy before it vapourizes and goes
back to the compressor. Wouldn't this mean that at the liquid stage at the evaporator, it is indeed able to produce more cooling?

I'm unsure how it behaves in the condensation stage, and how much effort or work is required to condense R134a compared to R12, which may be where it could be less efficient, as it does run at higher head pressures.

Saturation pressure curves appear to be very similar between the two which would indicate to me there would not be any abnormal amount of energy at the condensing stage required to saturate the refrigerant.

The only thing I have noticed is around the time when R134a began to replace R12, most cars switched to much more efficient condensers,
I'm unsure if this was to account for the new refrigerant, or simply to begin designing systems that can work with less refrigerant.
Research I have done shows that R134a does not have decreased thermal conductivity than R12 so I am trying to understand why it's universally accepted as a less efficient refrigerant.

I would appreciate any advice or an explanation of how I can compare these two refrigerants.
This is not for a project but more so for my knowledge of trying to understand the subject.

Thanks.

RE: Comparing efficiency of R12 and R134a with properties ?

Let's not forget that economics tends to drive product development, so there may be many reasons for settling on R12 prior to its downfall. Cooling efficiency might not have even entered into the equation. It might have been more efficient at removing money from your wallet.

TTFN
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