A Simple Piping Practice
While there are various line lift, sizing and trapping guidelines depending on oil and refrigerant type there is one guideline we can all understand easily and remember to apply and this is to slope suction lines towards condensing units / compressors.
Keeping the suction line sloped toward the compressor, especially with long, overhead lines helps to return the oil back which assists with capacity and lubrication resulting in fewer issues.
A good general rule is to slope the suction line 1/2″ per 10′ of horizontal run.
Short and simple but often forgotten.