I'm about to choose between two Trane contractors for a new furnace (xv90)/compressor system, both of which appear to me to be very competent/professional. The only difference in the quotes is that contractor A is offering an xl14i with R-401 and "new ducting (R6.5) duct board insulated duct work".
Contractor B is offering an xl14i with R-22 and new ducting "26 gauge metal and 2" FSK". Don't understand what the R value of this equates to??
All else is identical. Contractor A is $500 more expensive, but I can likely get him down to the same price.
What should I do?? If it makes any difference the house is located on coastal Massachusettes. I'm inclined towards contractor A bc (i) I understand that the ductboard will be quieter and in a residential application like this stand up just as well as the Metal, and I "think" it might have a higher R value (?) and (ii) I'd rather go with the newer R-401.
Any suggestions would be very much appreciated. thanks!