Found insulation stuffed inside boiler exhaust vent

2468ben

After a nice father's day present of a burst indirect WH, local company made quick work of replacing it, until they turned on the oil boiler (buderus) and noticed the airflow was low. It's direct vent, through the wall, so they took off the vent hood outside... and found a bunch of sooty fiberglass stuffed near the end.

Like more than a square foot of batt shoved in the 4" pipe. The pipe is insulated, intact and the vent hood is screened, so the batt's too big to migrate from the wall, or get snuck in by an animal.

Trying to figure out why and when. Only other recent work--
1. Boiler tune-up in April, then guy came back the next day when the burner kept turning off after half a second. Adjusted something, said direct vents are weird sometimes and left. Only guy who's been servicing it for many years, but a man of few words so I never really understood the boiler cycle/venting until the WH tech explained it.
2. MassSave blew some cellulose in the eaves, and did a before/after blower door test. My best guess is maybe they unscrewed the exhaust pipe, plugged it and forgot to take it out later?

Or is this some secret New England technique for reducing condensation and icicles in a wall vent, and I gotta stuff it back in there by December.

EdTheHeaterMan

My money is on the MassSave contractor. Sometimes their engineers are not of the "Rocket Surgery'' caliber. The term engineer is used sarcastically

mattmia2

Is it fiberglass with binder or the pure white stuff? Could maybe a piece that got sucked/blown from the combustion chamber somewhere.

2468ben

mattmia2 said:

Is it fiberglass with binder or the pure white stuff? Could maybe a piece that got sucked/blown from the combustion chamber somewhere.

fiberglass with binder, like it was pulled off an old batt. Not the pure white stuff.

mattmia2

Probably stuffed in for the blower door test.

HVACNUT

So MassSave is an oxymoron in this instance. 

Was the blower door test before or after the April tune up? 

Steamhead

Field makes a blocked-vent switch for oil boilers:

https://www.supplyhouse.com/Field-Controls-WMO-1-Oil-Fired-Secondary-Safety-Kit?utm_source=google_ad&utm_medium=shopping_neutral&utm_campaign=Shopping_Neutral_New_users&gclid=CjwKCAjwv8qkBhAnEiwAkY-ahmXGW0TpVr-azIHCj-7eMI5ElEYX2hYBRiyoHYVMzk2hYOxYoAtMtBoCcEYQAvD_BwE

2468ben

Thought I'd give an update on the off-chance it matters -

MassSave came by for an inspection, sweared up and down they never touch the exhaust for a blower door test, and thought maybe it was malicious. If it was then they did a real crappy job, and based on our few conversations, the only person my boiler tech doesn't like is George Soros.

Only other thing I noticed is that before, in freezing temps I'd see a little steam outside from the direct vent during a run. When they took out the batt in May, they adjusted the boiler again and now no steam. I assume that's a good thing for a non-condensing boiler?

SuperTech

mattmia2 said:

Is it fiberglass with binder or the pure white stuff? Could maybe a piece that got sucked/blown from the combustion chamber somewhere.

Buderus doesn't have any refractory insulation lining the chamber.  Someone put that there on purpose. 

Intplm.

This reminds me of the story about the mason who would install a pane of glass in a chimney passage. Then Brake the glass only after getting paid.

EBEBRATT-Ed

That is messed up.

Could have caused a C0 or soot issue.