I really don't want to expect any silly mistake from professional technicians who installs something crucial for living, because when something happens it is always me and my family who suffer. The IMS installed heater and AC units a couple of months ago and the AC was working fine during the summer. But when I turned on the Brand NEW heater in cold weather, it didn't work at all. It is so rediculous and painful. Now I have to spend another night without heat in my house. Thanks to the customer service who doesn't care the customer.