hi guys,

A week ago i was changing a txvalve and saw an orifice inside the txvalve , i was told that tx valves are similar for many systems- i mean one of same size range (tonnage of refrigeration) but it is actually the orifice which controls the flow of refrigerant, it has got a number written on it 0,1,2,3,4,5 etc. once the pipe sizes have gone bigger or the capacity need is greater and it cannot be met by one size tx with the best combination of orifice. it goes to a bigger tx size and so on again orifice combination.

i wanted to ask how do you determine which number orifice is required for the job. i know in one case of replacing faulty tx, you can always look at the faulty tx orifice and use the similar one , but in a very bad scenario can be tricked as well having to follow mistaken orifice and keeping the root problem with the system.
please try to understand

thanks