Confused over gas vent clearances. One page states min 1 foot roof clearance up to 6:12 slope. Another page says all metal vents must be min 2 foot clearance. Can someone please clarify? Thanks.
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I just received an email from a student of the course with a good question. “Hello, I need help with the following question as my online research has provided conflicting responses. In Nova Scotia Canada, can a Coal Furnace and oil furnace (hot water baseboard) share the same chimney? The Oil furnace does have thermostat controls (2 zones, 2 thermostats) however the Coal furnace does not have any thermostat controls. Thank you.”
Good question. And the answer is inside this course at InterNACHI® - International Association of Certified Home Inspectors. A solid-fuel-burning fireplace, stove, or heating system must not connect to a chimney venting another fireplace, stove, or heating system. This is prohibited. (Refer to 2021 IRC M1801.12).
A solid fuel-burning appliance or fireplace must not connect to a chimney that serves to vent another appliance. Each solid fuel-burning appliance or fireplace must have its own dedicated independent chimney or vent. Solid-fuel appliances must not share a chimney with any other appliance or fireplace.
Here’s why. Solid fuel-burning appliances produce creosote on the interior flue liners of chimney stacks. Creosote is highly combustible. If there’s a chimney fire, other connections to the chimney could allow the fire to travel out of the chimney and into the building. Chimney passageways can become partially blocked by creosote formation, which can force vent gases from another appliance to exhaust back into the building.
Thank you for the checkup, I have been working on the course agenda with my regular work schedule. Have been a lot of traveling and some of these classes are pretty intense and working them as I can.
So I have two question here. First, is I was looking for the how to inspect fireplace, chimney and stoves checklist. But I am having trouble locating it. I had found it once before and now I can not seem to locate it. Does anyone have the link?
Second is I am inspecting a wood burning fireplace in a home. I have noticed that the inside of the fireplace is showing signs of efflorescence on the walls of the brick inside the fire chamber. The firebox itself sits roughly 6 feet up from ground level on the outside of the house. If there are no signs of efflorescence in any other locations and there are no signs of any capilary action below the firebox. Should it be dedueced that the capilary action that lead to the efflorescence was due to rain water getting in through the chimney cap?
There has to be moisture coming in at some point. What areas of the fireplace have you check? Have you checked the flue? Let me know what you have found. I am just beginning this course. Is that salty surface found anywhere else near or on the fireplace?
I’m very excited for this fireplace, stove, and chimney course! My other friends and family just don’t understand a statement like that. Thank you for such great material to learn from.