I am having a problem with my York Tubular Heath Exchanger, not sure of the exact model# but the manual shows model#s PS8/FC8s/FL8s/LC8S/LL8S. We keep the temperature set low while we are sleeping and while at work. When the sytem kicks on to start warming the house the system will come on but the fan is not blowing. We restart and then it works fine until the next morning. We had someone come out last year for the same thing and they said everything was fine it might have been a short from having the christmas lights on. This is the only time of year that this happens. What do you think? FYI it has been exceptionaly cold -15 one day and the 10 the next.