Air Conditioning - Charge compensation for line kit

I recently had my central air unit replaced with a heat pump. My line set was deemed in good shape by the installer and reused. After connecting the A-coil and pre-charged compressor unit, he ran the system and made some minor charge adjustment relying on pressure readings. He couldn't tell me a weight specific charge he added to compensate for the 30' line set. Is there a "rule of thumb" of what to add to keep the pressure side liquid?

There is no rule of thumb.

Is the new system same tonnage as old? Indoor coil been replaced? system R-22 both new and old?

The freon charge in any units . Is all in what the unit calls for at what the temp it is running at the time. So this would also take in the fact as to how long the line is.