Arrived at customer's house for 2 condenser 4 head Ductless split system tune up. On arrival checked units on east side of the house. Neither was cooling efficiently. Went outside to condenser and unit was freezing up on discharge side. Unit was low freon. Showed to customer and suggested we fill with freon. Customer agreed. Added 2 lbs and units now cooking dine. Both units could use cleanings. Customer has been doing dusty house work and leaving units on. Next checked units on Westside of the house. This unit has had a leak check before period units are not producing proper Delta T. Went outside to condenser and hooked up gages and gages showed low free on. Due to us not doing this install and not being sure of a proper install I am suggesting Every single connection be week chat. Not sure if the installers were using proper torque wrench settings or if they made connections properly. With this unit already having a leak check and I'm seeing low free on now I do not trust any conn