mkgrady
Senior Member
- Location
- Massachusetts
I'm looking at a cut sheet for a 10 ton A/C condensing unit. It operates on 208/230-3-60 and the MCA is listed as 40.6 amps. The existing unit has a #8 wire and a 40 amp CB feeding it. 40.6 being more than the 40 amp wire can handle tells me I need to upgrade the wire size to #6. What I am confused about is that the sheet states that the data is based on a system of 230-3-60. I will be connecting 208 not 230 volts. How does that affect the MCA? Does it make it larger or smaller or stay the same? If I could get the mca below 40 amps I won't have to change the wires.