expansion valve adjustment

[reftec021702]

Dear fellows:

I have two YORK 10-ton dual circuit evaporators not working at full capacity. Superheat measurements indicate values above 25 degrees F. I would like to reduce the superheat setting of the valves, but they seem to be of a fixed non-adjustable type. Is there any way to make them open a little bit, or need to change the all ? Thank you!!

 

[chilled]

As a refrigeration mechanic I watch this forum regularily to get a very valuble perspective on design and engineering.

Adjusting expansion valves is trade talk.

Go to

http://hvac-talk.com

You'll find more than enough people on that site willing to impress thier 'wisdom' on anyone who asks.

 

[imok2]

You may have other issues such as
1.Do you have the proper line sizes
2Is the head pressure high enough to give you a full head of liquid at the TXV
3.Is the sub cooling between 10-15*F
4.Do you have a restriction in the liquid line (bad drier) etc
5.Do you have the correct CFM air flow
6.TheSuperheat should be in the range of 12 to 20?F, no more than 25?F 6" from compressor suction valve. Superheat in the normal range indicates the valve is probably working properly, but further investigation should be made.