vent connector slope

What do you think about this vent connector slope for a natural gas fireplace/stove.

Could be fine…I’d have to see the manufacturer’s install instructions to be sure.

I’d be more concerned if that chimney was located on an outside wall where it will be cold upon unit start up. It will then have to push a column of cool/cold heavy air up out of the flue before it can warm the flue and get the recommended draft for efficient, safe operation. Those of us that have been in WETT for a number of years would like to see exterior chimneys (even the insulated steel metal types) banned. A chimney should always be installed through a warm area of the house so that’s its warm with a column of light bouyant air creating draft without help or chance that it will draw.

In 1989, I worked on the local portion of a cross-country study on IAQ. It found that 39% of oil and gas installations had draft problems and were borderline for gas spillage upon startup!! Some corrected within seconds but some took almost a minute…too long to be spilling combustion gases into a living space! It would take very little to tip the scales to longer or constant spillage.

WETT #572
Master System Advisor

Thanks, great information. Very good reminder regarding the chimney location. This chimney was actually an external chimney installed several years after the home was built with a 2 inch gap between the masonry and the cladding and lateral supports every 10 feet. I sometimes find spillage on gas appliances with my carbon monoxide detector until it reaches its steady state.