The biggest problem at that low suction will be gas density - you will not be able to tolerate additional suction line pressure drop easily.

The ideal way is to arrange the suction line for 'sewer-flow' oil return. That way you can make it even larger than needed and still have good oil return without taking concern for gas velocity.

If this is impossible and you can't get both (pressure drop and gas velocity) to balance well, first; start with using a good oil separator at the compressor to keep the oil content of the liquid to the very smallest amount.

You really should be doing that anyway to keep your condenser performance at it maximum.

Either curve the line sizes yourself (which would be more satisfying - but don't forget your bends and 90's) or have Bitzer work them out for you.

PHM
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