No heating call. Upon arrival system was operational. Attempted to recreate issue but was not able to. Homeowner stated it has occurred in the past 2 days early in the morning except for today. He hears the system power up for about 10-20 seconds then power off, and will continue this way, he only feel cold air. I have attached a list of possibilities. If issue persist or worsens we will need to come back out. If system only acts up in the morning we will want to schedule appt closest to that time. System operating at time of departure.
