Replaced a 13 year old 5 Ton Goodman heat pump with a new 5 Ton 16 Seer unit and top of the line Honeywell thermosat to take advantage of all the functions the heat pump offered. About 3 weeks after the installation cooling stopped and system reported a B1 error code. The company who installed the unit came out, checked the unit over and reset the fault. After that the system started cooling and worked for about a week before doing the same thing. This time the error code would not clear and the technician had to order a new control board for the air handler unit. 3 days later the board arrived and was installed... all worked properly for another couple of days and then stopped cooling again. The short of this story is that in order to get this "new" unit working, sorta, on the advice of the technician and since the local Tech Support Person for Goodman heat pumps had no answers a Honeyswell VisionPRO thermostat was installed. This got us through the summer months and we were grateful that the heating function seemed to work OK. We're now into another cooling season and no one has an answer to whats wrong. In fact the system has gone down several times with the same B1 error code. I understand that this is not an unusual problem and wold appreciate seeing posts from anyone else experiencing this problem. I must say that if it weren't for the quality and knowledge of the company we're woring with we would have spent the summer in our room over the garage which has a fully function, lower tech, through the wall 14 year old heat pump.