ActronAir Indoor 8-Zone VAV Board is the factory supplied and fitted zoning control board for ESP Ultima indoor units, providing Variable Air Volume control across up to 8 independent zones for precise individual temperature management in each room. A failed 2020-169B board causes loss of zone control and VAV modulation — fit the 100% Genuine ActronAir 2020-169B to restore factory zoning performance. Low voltage inputs only — connecting 240VAC will damage equipment and void your ActronAir warranty.