Fireplace Ash Dump

[Jerry Simon]

Masonry fireplace with an ash-dump door leading to an enclosed, masonry ash-dump chute (the kind with the metal clean-out door on the face of the chute, down in the basement). When I looked up into the chute with a mirror and a flashlight, I could see the metal flue pipe for the water heater.

The one masonry chimney has two flues; one for the fireplace and one for the water heaters. I always thought the ash-dump chute had to be isolated from any furnace or water heater metal flues that might be running into the same masonry chimney - usually I'll see a masonry/block wall built to separate the ash-dump chute from the metal water heater flue piping area.

Well...not that I always thought such, but I never saw such - where the water heater metal B-vent shared the enclosed ash-chute area. I worry there is a potential for fireplace smoke & CO to get into the water heater metal flue piping and perhaps enter the house. Sounds like a stretch for that to happen, but since I never saw such before, the question remains; is this set-up kosher?

Thanks for any thoughts, insight, code references...

[waynesoper]

Fireplace flue cannot be shared. NO, NO,NO NINE

[Jerry Simon]

Fireplace flue cannot be shared. NO, NO,NO NINE

Wayne,

My post is rambling and confusing. The chimney flues are not shared. The metal water heater flue pipe simply runs through the fireplace ash-dump chamber, on its way up its own chimney flue.

[Bill Kibbel]

I don't think there would be anything at all in the code or NFPA 211 about the construction of ash pits - just stuff about the door.

If this water heater B-vent was the "vent connector" from the water heater to a vertical flue, vent or chimney, I think it has to be completely accessible for inspection, cleaning and replacement.

[Tom Raymond]

"...it has to be completely accessible for inspection, cleaning and replacement."

Especially if you plan to dump the fireplace ash into it[:-banghea

If the ash dump door in the fire box isn't sealed the flues are being shared, and the CO, CO2, and water vapor from the water heater exhaust being drawn into the fire box can't help cumbustion any at the fireplace.

Tom