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[A.Mortezania]

Dear Friends,

Find my photo at attachment.
I took a photo form somewhere. Would you please let me know why someone installed check valve on equalizer line of expansion valves ????

I know that expansion valve should be near the distributor and also all of expansion valve such as power and body must be under insulation foam, My question is just : Why someone installed check valve on equalizer line ? Is it true ? I asked him, He told me I have two valves (after and before of expansion valve) and check valve on equalizer line. When I want to change orifice I close these two valves and check valve do not let R22 to go out form equalizer line of system.

Is this think OK ?

Sincerely your.

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