Last summer I had a York YZF036 heat pump installed, with an F6FP042 air handler. During the installation, I heard one of the installers complaining about the TXV that was sent with the system. While they were installing it, I wrote down the part number for future reference. It was S1-1TVM4F1. Looking this part up later, I found that it is normally supplied for 1.5 to 2.5 ton heat pumps. Things seem to be okay - our coldest morning has been 31F (in Santee, CA) and my house has been kept at 68F during that time. Do I need to take this up with my installer? Thanks!