Our 20 year-old Trane XE heat pump have up this weekend, the compressor apparently blew. The tech that came out recommended replacing the heat pump with another one from Trane (still with R22 refrigerant) and keeping the old air handler. Getting a new system is another option we obviously consider, a two stage system or even the new Carrier Infinity Greenspeed system. The tech said he recommended simply replacing the old heat pump since the new refrigerant (R-410A ) requires a higher pressure and he has seen many failures of these new systems. True? How reliable are the systems nowadays? If the installation is done right, there shouldn't be any more problems than before. Also, the copper lines for the refrigerant would have to be replace for the new R-410A, is that correct? The brands (Trane, Carrier etc) are less important to us but the new Carrier Greenspeed seems very interesting. What would be good recommendation for the Mid-Atlantic region, north of Baltimore. I know that the installer should do a Manual-J heatload calculation to properly size the system, and I have done a lot of air sealing and insulation work to the house (same age as the heat pump) so the system could be smaller than before. Does anybody know when the Carrier fall rebate program starts, by aby chance? I know that Trane's is currently in effect, as this would influence the pricing for the systems.
Any input is greatly appreciated.

Thanks.

Klaus