Air-Sealing Penetrations from Gas/Electric Lines
the74impala
| Posted in General Questions on
The area below the rectangle the lines emerge from is what I would describe as an ash pit. I think I can seal it below where the line come in there, but in the fireplace, I would like a solid bulkhead fitting or rubber flange to seal them the best they can be. I have looked at a variety supply website, but haven’t found what I am looking for yet. The gas line would have the 3/4 – 1/2 reducer replaced then black pipe mounted to the interior of the firebox with the shutoff at the end. The flex conduit just goes to an outlet box.
Any ideas?
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Replies
Seems to me the electric wire is rated for something like 75°C so it would seem safe to fill the gap with foam insulation (Greatstuff)
Walta
I was hoping to have something that was more mechanically rigid or significantly more flexible and retentive.
You won't find a grommet that will seal into an irregular hole like that.
I would use Great stuff as Walter mentioned. If you want something a little more durable than that, use Loctite's Titefoam, which is denser and more solid than Greatstuff (and it costs more too).
If you want something rubber-like, you could possibly use elastomeric roof sealant, but I really wouldn't recommend trying that. Canned foam is really the right product to use here. If you want to limit how much canned foam you use, I'd cut a block of XPS to mostly fit the hole, then foam that block in place and foam the lines into holes in the block.
Bill
Boy, I didn't say what I should have. I plan to use a piece of metal or plastic, like cutting board material, to cover over the rectangle. Then have holes in it to allow those through. The bulkheads/ fittings would then keep things sealed up. Sorry for the lack of information. The can foam makes sense based on what I first posted. I will caulk/foam to seal the edge.