# Thermofluids Air Conditioning Unit TS diagram

1. Mar 11, 2016

### Mechaman

1. The problem statement, all variables and given/known data
To plot a TS diagram given the relevant data here http://imgur.com/Q9RNL8P for an air conditioning unit.

2. Relevant equations
R134a is being used in an air conditioning unit, steam tables for -5hf 0hf and -5sf 0sf written below in exrapolation.

3. The attempt at a solution
I've extrapolated the -2.7 to find the base pressure that goes into the evaporator from point 4 here http://imgur.com/zl4eIGJ

And finally this is my plot from what I understand http://imgur.com/XE4HVtt

I can see that point one is superheated so wouldn't I take the lower pressure as the -2.7degrees.

• But the pressure at -2.7 degrees is 2.7006 bar
• and the pressure of 5.2 degrees is 2.554 bar
How is the warmer temperature a lower pressure?
Am I right in setting the bottom pressure line at the -2.7 degrees?

Thanks for reading I would appreciate any help with this.

2. Mar 16, 2016