Performed first year furnace cleaning; system was not getting up to temp upon arrival found a clogged 201 air filter the system was going out on high limit due to the clogged filter, I replaced the the 201 filter for the mean time no charge because we upgrading to the electronic air cleaner, I then removed and cleaned the burners along with the flame sensor, I then cycled the system on and checked gas pressures, then performed a combustion test verifying no CO in the airstream. This system is currently operating normal and heating at 48 degrees at this time. We will have to return to install the air cleaner. Job complete