Flue connection

[John Evans]

PVC vent from gas furnace connected directly to lined masonry chimney flue. This connection does not appear to be correct, any opinions?

[Larry D. Kage]

Some use the old chimney as a way to get the pvc pipe outside. Did the pvc run up and out the top of the chimney?

[John Evans]

The PVC does not continue to the chimney top. This termination may not provide adequate drafting. In addition, condensation may cause chimney deterioration. A water heater is also connected to the chimney flue. Same drafting and condensation concerns. From my research, high efficiency furnaces gas furnaces and water heaters should not be connected to a masonry chimney. This may be the first time I have seen a PVC vent connected to a chimney. Metal flue connections are quite common.

[Brian A. MacNeish]

Originally Posted by jevans

The PVC does not continue to the chimney top. This termination may not provide adequate drafting. In addition, condensation may cause chimney deterioration. A water heater is also connected to the chimney flue. Same drafting and condensation concerns. From my research, high efficiency furnaces gas furnaces and water heaters should not be connected to a masonry chimney (or existing oversized uninsulated metal chimney). This may be the first time I have seen a PVC vent connected to a chimney. Metal flue connections are quite common.

About 10 years ago, a family of four in Saskatchewan was killed by CO after their older metal chimney became blocked with frost/ice from condensation during a very long/cold spell of weather. The high efficiency gas furnace had been simply vented into the existing flue/chimney.

Read the HVAC manufacturer's instructions!!!!

[James E. Braun, CMI]

In Missouri, high efficiency furnaces got to be piped directly outside, no termination in chimney is allowed. I use to own a heating and cooling company, that is how I know.

[James H. Bushart]

Originally Posted by jbraun

In Missouri, Furnaces got to be piped directly outside, no termination in chimney is allowed. I use to own a heating and cooling company, that is how I know.

Not in most of Missouri. Furnaces are allowed to vent into the child's bedroom if that is where the unlicensed and unregulated HVAC tech puts it there.