Building #9 was having issues. Cause of the issue was a bad heat relay on north system. This is what caused the thermostat to fail and damaged the low voltage fuses. Replaced relay and tested system operation. Found a minor gas leak on the north system. Repaired leak. And the middle system was having a polarity issue with the board. Adjusted the wiring to solve this issue. All 3 systems are operating in heat and ac mode.