How would you seal this gap under central boiler hydronic baseboard heaters that only get warm, not hot.
How would you seal this gap under central boiler hydronic baseboard heaters that only get warm, not hot.
You need the gap. Baseboard heaters work by heating the air around it, causing it to rise. This rising air is replaced by the cool air being displaced. By having a gap under the heater, the cool air has a place to go and be heated. This causes a draft that allows the full room to be heated, not just the area around the baseboards. In essence, the gap allows the heater to be more efficient.
If you insist on covering it, use a sheet of decorative metal that is at least partially open to allow airflow through it. Even that will reduce efficiency, but it wont be as bad as blocking it.
9I am referring to the small 90° gap between the flooring and the metal where you can see bits of exposed concrete. Are you saying that gap shouldn't be sealed?
5My misunderstanding. I thought you meant from the heater to the floor.
To fix the gap you were talking about, you could do some acrylic caulking. You could do high heat silicone if you were worried about the heat, but the acrylic should be fine. Check the tube for the allowed heat range. The silicone will do vetter against the expansion and contraction, but you'd never be able to paint it. The acrylic would be paintable. But had a high chance of cracking.
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Caulking, a 100% silicone caulking shouldn't shrink. Just curious why are you trying to seal the gap?
3My approach would be to get a tube of silicone caulk that handles a decent range of temps and a length of hose that fits over the tip of the tube to reach under if the caulk won't reach on its own.
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