This picture shows an improperly installed gas fired water heater flue pipe. The flue pipe is pitched downward before it enters the chimney. The flue pipe should be as straight as possible with a minimum number of turns or elbows and should have an upward pitch of 1/4 inch per foot from the water heater to the chimney. The potential problem with an installation such as this one, is that exhaust fumes from the water heater could back out at the draft diverter hood. The exhaust contains carbon monoxide (CO) which is a deadly gas at high levels.
A gas fired water heater requires a permit from the local town/city Plumbing Inspector. The permit tag from the local plumbing inspector was not found on the gas pipe connection to this water heater tank. There may be potential legal, insurance and or unexpected hazards as a consequence for a homeowner when proper permits are not obtained.
Photo taken by Dennis Robitaille of Able Home Inspection.