Boiler Vent - repairable

Old 12-17-19, 10:55 AM
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Boiler Vent - repairable

There's rust on lower part of the vent and I'm not sure if it's repairable or the cost of repairing it is high that I'm better off replacing the boiler.

It looks more complicated than the vents parts at the big box stores.
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Old 12-17-19, 11:29 AM
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The narrower section at the bottom and attached to the boiler extends up into the next wider section but leaving a gap about an inch all around rather than make a tight fit up there.

It is not hard to find a new section of narrower pipe to replace the old rusty section with (after the older section rusts out leaving a hole in it). It is more difficult to obtain or fabricate some smaller pieces of sheet metal to keep the lower section centered within the next, wider, section and look good to an inspector contrasted with using coat hanger wire to hold it in place and also tie the wider section to the ceiling joists above for support..

Furnace cement (comparable to putty or caulk but that withstands high temperature, can be used to seal the new narrower section to the top of the boiler.

This kind of venting uses the high temperature of the exhaust gases to rise up the chimney/vent pipe and not come out the gap between the lowest narrow pipe and the next wider pipe above,
Old 12-17-19, 02:35 PM
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The issue is getting the old draft hood off. Its apparent you have flue pipe condensation issues.

You need to address this when replacing the boiler. Often its from cast iron heat emmitters and the boiler not getting up to temp fast enough.

You most likely need some type of boiler bypass piping installed on the new boiler of primary secondary piping scheme installed to combat the issue.

Last if you do want to replace the draft hood, they are boiler specific. The distance from the top of boiler to the bottom of the draft hood is a specific distance per each size boiler.

You may find writing stamped on the draft hood showing this #.

Then you can often make your own to replace.

IMO because of the condensation I would thing the heat exchanger on that boiler is so clogged and rusted that I would just replace the boiler. Most likely you have draft issues because of that and dangerous deadly CO gas may be being released in the home.
Old 12-17-19, 02:37 PM
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