Removed defective flare from the copper lineset and refitted connection with new flare. Used nylog thread sealant and tightened bolt. Pressurized system with 200 psi of nitrogen and leak tested connection with soap bubbles. Vacuumed system down to below 500 microns. Weighed in refrigerant charge with digital scale (3.10lbs) r410a. Tested system and measured indoor temps. Soap bubbles connection again, system is working properly at this time.