R407 refrigerant

[Brian_UK]

It gets you worried, doesn't it Frank ??

[Snowman123]

You'll need abot 4.5 to 5.0 bar suction pressure.

[JCole21961]

Thanks. What are the normal upper and lower pressure values for R407 under the normal extremes of weather in heating and cooling mode? I have read in another report that R407 is about 40% less efficient than R22 in cooling mode. Is this true?

[frank]

I have read in another report that R407 is about 40% less efficient than R22 in cooling mode. Is this true?

Not quite true. R407C is fine for medium temp applications and is about 5% less efficient when compared to R22.(Obviously there is also the glide factor to consider). When R407C is used for applications with evaporator temps lower that +5C the efficiency really starts to drop off. I've got a few detailed research notes on the subject but I'm sure you can find it on the net by "Googling"