Heating issue call. After diagnosing, found customers thermostat was working intermittently. Replaced thermostat. Also performed both clean and checks on both condensing unit due to maintenance plan. Tested capacitors, contactors, compressor amperages, fan motor amperages, blower motor amperage and capacitors. Washed out and cleaned condenser coils. Checked refrigerant levels. Used 3 lbs between both units due to both being low on R22 refrigerant. Added leak sealant. Both condensing units are cooling adequately and are at accurate efficiency levels at this time.