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A.Mortezania
01-03-2017, 07:07 PM
Dear Friends,

Would you please let me know why on all catalogues show that we must install equalizer line after bulb of expansion valves ?

Find my photo below.

Sincerely yours.

14645

mad fridgie
01-03-2017, 07:27 PM
In the past when manufacturing was not as good as today, the seal between the equalized chamber and the main refrigerant flow was not always perfect. A small amount of refrigerant could pass down the equalizing line, Generally not enough to effect the refrigeration process, but enough to effect the sensing temperature at the bulb, if it were fitted before the bulb. So that is why it is fitted after the bulb.

A.Mortezania
01-03-2017, 07:37 PM
In the past when manufacturing was not as good as today, the seal between the equalized chamber and the main refrigerant flow was not always perfect. A small amount of refrigerant could pass down the equalizing line, Generally not enough to effect the refrigeration process, but enough to effect the sensing temperature at the bulb, if it were fitted before the bulb. So that is why it is fitted after the bulb.


Thanks for your help

Segei
01-03-2017, 11:25 PM
TEVs with equalizing lines use for the evaporators with significant pressure drop. Equalizing line gives pressure in the bulb area to TEV to provide correct feeding. Evaporators with small pressure drop don't have equalizing line. In your drawing distributor gives significant pressure drop.