Home has 2 high efficiency furnaces located in the attic with relatively long, PVC, drain lines. One of the systems has a frozen drain line the other one is still operational. The system that is operating has had a damper motor fail. This system heats the master bedroom and the upstairs bonus/playroom area. I have replaced the damper motor today labor only. Recommend that the customer add automatic electric pipe protectors. Technician send a photo of item.