R290 LBP Compressors at Low Temperatures

[kay86]

Hello everyone,

I'm looking into how R290 LBP Embraco compressors perform, especially when it comes to the efficiency data they provide.
I've noticed that some models list their power consumption in watts and the thermal watts displaced down to -40 degrees Celsius. However, others only provide these details down to -35 degrees Celsius. Does this mean that compressors not specifying performance at -40 degrees cannot reach these temperatures, or is it possible that the manufacturer simply did not test them at this lower temperature? I always consider the condensation temperature at +35 degrees Celsius in my evaluations.

Any insights or experiences with these compressors would be greatly appreciated!

Thank you in advance.

[csrbvba]

I think that at -40° the high pressure temperature would be to hot. -40° is almost vacume, with the pressure lost would be lower. Probably needs a two steps.

Correct me when i am wrong, so i can learn.

[kay86]

Hello, thanks for your reply.
At -40C the pressure chart for R290 says 1.4 PSIG so yes it's almost vacuum but it's indeed doable. Infact, picture attached is what the data sheet for the compressor says about one particular R290 compressor that I picked. However, I am curious to understand why, for similar LBP R290 compressors, the chart only goes down to -35C.2389752934789237589.png

[Orsus_KR]

Hi Kay86:
do you find these "rated only down to (-)35C evp temp" models either at the lowest end of LBP range (or) at the highest end of the entire LBP range? The internal construction of that specific model - with respect to internal gas superheat, motor design, lubrication etc. - may constrain that model compressor to run SAFELY at (-)40 evp and (+)35 cond. It is advisable to stay within recommended compressor envelope of mfr.