Generally I think highly of MoreVent, however this last time I was left with very mixed feelings. We have a contract with MV, so they come every six months. About a month and a half after the last visit I felt one of the systems was not working well and called. They very promptly came and confirmed that indeed there were two problems; in fact, it was so bad they needed to SHUT MY HEATING DOWN cause it was a safety hazard. While I appreciated the technician's promptness and concern, the big question remains: How come this was not found by the regular checkup? I have been told now service people will be checking this in the future, but having to shut down my heat when we had really cold weather, when supposedly we are paying to avoid something like this, was really not cool.