Fighting issue withh RPJ 2 unit. Furnace turns on, lights up for 20-30 seconds, then shuts down right before the blower kicks in. Get 2 red flashing lights sometimes. Shut it off for a couple of minutes, and then 70% of the time it will run appropriately, and 30% of the time it will restart 2 or 3 times and will shut itself down until I restart the cycle. At least at 3:00 AM I'm able to restart the furnace eventually. I cleaned contacts, unplugged and replugged everything unpluggable. Do I need to call a contractor?