Performed a two system maintenance checking cooling. Checked indoor units capacitors, filters, amp draws, checked drain lines, everything checked out properly. Checked outdoor units pressures, amp draws and capacitors. Everything checked out good. I did find that both contactors are pitted and getting close to failure. Also outdoor coils need to be cleaned. Backside is completely clogged. Upstairs unit may have a txv issue or low Freon issue. Temperatures outside are too cold to determine just yet.