We're changing out our old freon unit to a 15.8 SEER Amana 2 stage 410 unit and are not sure if the coil needs to be changed. Our contractor mentioned that theres kind of an industry argument about whether cleaning the oil out of the old coil is acceptable or not, and I just wanted to get some opinions. The existing coil is from 2004, and its a Carrier CE3AXA060000ABAA. It says it can use 410 with listed units. I don't know the SEER rating on it, and our guy is checking on it, but if it can be used, what are we losing by not changing to a new one? Its a huge expense for the new one, so it would really have to save a lot of electricity to make it worth it.
Any input would be greatly appreciated!