I have a York Affinity 5 ton split system model number YZE06011A with coil model MC60D3XH1A. R-410A system. It was put into service in Feb-2007 when we built our house. The gas furnace is in the attic along with the failed coil.
coil replaced 8/18/2010
added freon 3/29/2012
replaced service port valve down assembly 7/09/2012
coil leaking again 4/19/2013
The first coil was a blue fin. The currently failed coil isn't blue fin but still has copper tubes. York won't fix since warranty was only 5 years & this is 6 years old. I suspect the coil may have been leaking in 2012 when more refrigerant was added but that is neither here nor there. York's replacement is the same copper tubes that resulted in the second one failing after 2.5 years.
Formicary corrosion (ant's nest) is the root cause of both coil failures. I don't know if it was internal or external to the coils though. If external, then not much I can do to reduce the organic acids in the ambient air, that I'm aware of at least. If internal, then it doesn't matter now b/c I'm not getting another coil from York anyway. I realize that formicary corrosion is an industry wide problem but some mfg have implemented some sort of solution by either tin coating the copper or moving to an all aluminum coil. I'm trying to find another brand but fit & AHRI matching might be an issue.
I'm considering the following & would appreciate your thoughts. I'm still waiting on the Trane & Carrier contractors to get back with a quote. I'm mostly worried about proper matching. I do understand that the contractor selection is very important, but want to learn as much as I can to ensure that everything else goes well. I've tried to already reduce the field to contractors that I would actually use prior to getting a quote so as to not waste anyone's time.
Bryant model CNPHP6124ALA from contractor A
Payne model CNPHP6024ALA from contractor B
What's the difference between the two coil model #s that I've been quoted. Both are all aluminum units (with copper stub outs). The Bryant coil is from their Preferred line. Why would I not get a coil from their Evolution line? Pricing is almost identical so far.