Bjenks
Senior Member
- Location
- East Coast of FL
I have multiple scenarios for VRF AC systems and AHU disconnect requirements. If it is a ductless unit where the AHU gets its power from the CU, I use the CU as the only disconnect. But if the CU is a multi-zone type that each AHU gets power from a dedicated unit I try and follow the rule that if AHU is on a dedicated protected circuit that is 300VA (1/8HP) or less I don't require a local disconnect and can use the breaker. But many times on large system I will connect 4-6 multi-zone AHU on a single circuit. My question Is once the total load on the circuit goes past 300VA shouldn't each unit now require a disconnect or is that irrelevant as long as the individual unit is 300VA or less? I am thinking the intent would be the circuit, but since I don't understand the reasoning for the 300VA exception I am not sure.