I keep getting code 76 on my rheem tankless unit. The heater is located in attic and controller located in master closet. There is an unshielded thermostat wire connecting controller and unit. Code 76 says unit and contoller having trouble communicating. I know magnetic fields accompany electrical lines and can cause interference on low voltage line. I noticed the teminals on rheem connect at bottom of unit then connect direct to the pcb board. However the terminals are not grounded. Will grounding these teminals solve code 76 issue?
