measure sub-cooling

[HARRY 7]

Can anybody tell me,which is the correct point to take high pressure to measure sub-cooling.At compressor discharge valve or at liquid line before the expansion valve???

[nike123]

For checking that you have enogh subcooling to prevent flash gas before TXV, at liquid line before expansion valve.
For checking refrigerant charge, at condenser outlet.
Pressure should be measured where temperature is measured. If not possible, than you need to take in consideration pressure drop from measuring point of pressure to measuring point of temperature.

[HARRY 7]

How can you calculate pressure drop nike??

[nike123]

How can you calculate pressure drop nike??

You could use Cool-pack.
But, if length of pipes and number of fittings are small you could round that pressure loss or ignore it, if you could picture in your head how much approximately that would be.
Try with excersizeing on real examples from your work by noting pipe diameters, pressures and temperatures, power of system and then calculate in Cool-pack. That will give you feeling.

[HARRY 7]

What is coolpack?

[r.bartlett]

Nike,

You're very patient

[nike123]

What is coolpack?

http://www.et.web.mek.dtu.dk/Coolpack/UK/index.html

[nike123]

Nike,

You're very patient

Yep!.......

[HARRY 7]

Thanks for the information nike