VENTING PROBLEMS AND SIZING SEMINAR An appliance that does not meet minimum draft standards is a common follow up problem encountered by Weatherization auditors, technicians and supervisors. This one day session covers venting basics, vent system problems and fixes, mid efficiency appliances and vent sizing using the most current edition of the NFPA 54 code book. Recommended prerequisite for this seminar is the successful completion of the Gas Heating Systems Inspection seminar.