Arrived onsite for issues with heating system heat pump; possible low refrigerant. Performed diagnostic and found the system heating at a 20 degree temperature rise with supple temp around 82. Measured r22 Refriferant pressures at 51/170. Measured ac temperature drop at 20 degrees 65/45. Recharged system with up to 1lb of r22. Increased r22 pressure to 65/200. Increased supply heat to 95 degrees. System seems to have a restriction possibly in the reversing valve. New system has been ordered and we’re are waiting on the manufacturer.