Suction and liquid line temps meaning for mini split in heat mode

Bben

Just curious if these temps can be used to help diagnosis reduced heat output on mini split:
Outdoor suction line temp: 115 degrees F
Outdoor liquid line temp: 78 degrees
Indoor unit heat output temp 85 degrees
(Outdoor air temp 38 degrees, indoor temp stuck around 68 with thermostat set to 72.)
I didn't use a high tech temp gauge, just my digital sensor so actual temps probably different, but is it possible that these spreads could indicate a low or high charge of refrigerant? (Assuming next step would be actual psi gauge test.) Thanks.

Ironman

The only way to assure the charge is right in a mini split is to weigh in the correct amount.

There are methods of “ballpark” checking, but not by comparing liquid and vapor temps.

pecmsg

Both lines are suction on minis