Anybody know what this is?

[billybek]

That isn't big enough to be combustion air for a gas fired appliance or a vent to remove products of combustion.
I wouldn't think that a central vac would be a possibility either as the box would fill up with dust an crap eventually.
I think Shaun nailed it with a radon ventilation system
Should have a pipe attached inside that goes to a small fan. The small fan pulls air from under the slab and vents it outside the house. The under slab is at pressure slightly lower than the basement preventing radon from entering the house.

[DerkPerk]

Originally Posted by cstreit

New furnaces require fresh air inlet.. Could have been one of those too...

This is way way too small and restrictive for any kind of appliance intake or vent.

Originally Posted by piscator

Entrance to the mouse disco? ;-)

This makes the most sense so far.

Originally Posted by Shaun @ Tru6

Radon relief vent

For radon, it should be above any other air entry point like a window.


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[Por_sha911]

It may have been the previous owners cobb job fix for some kind of ventilation.
Has the house been tested for radon?

[Zeke]

Originally Posted by cabmando

I'm on board with the central vac intake idea. I would think you'd know for sure though if you had a central vac at some point because unless someone did an extremely thorough job of removing it, you'd have plugs in the wall for connecting the vacuum tube and you'd probably have pipes that just come through the floor and terminate in the basement.. Central vac still seems like the most logical though.

For those asking about the furnace, you wouldn't terminate a furnace intake like that, or at least you shouldn't if you like your furnace to keep operating when it's cold outside.

Vacuum intake? You maybe should go back and look how a vacuum works.

[911 Rod]

Looks like a bat box to me. Did you find any empty coffins when you moved in?

[MRM]

If the prior owners replaced an old gas water heater with the current electric water heater it might be left over from then. If it is filled with insulation it sounds like it was an old vent or air intake that isn't being used anymore. If it is still open and air is flowing it was meant to ventilate or exhaust something current because if they removed something that used to use it they would have sealed it because they wouldn't have wanted uncontrolled air coming into the house. Is there a whole house air exchange in the utility room?

[flipper35]

Originally Posted by wdfifteen

I should have included that it opens into the furnace room. Whatever it vented was piped to it through a 1 1/2 inch pipe, I assume from someplace other than the furnace room.
MRM - there is an electric water heater in the room.

In the past, did there used to be a gas one?

[stevej37]

Originally Posted by wdfifteen

The furnace room opens into the garage. Its a big space. Anyway, it's a brand new furnace with piped in combustion air. The first furnace in the house (built in 1971) would have needed combustion air, but it's only a 2" hole. That's not much air.

Had my furnace replaced two months ago. New one has a 2 inch pvc for the intake air and the same size for the exhaust. The installer placed them about a foot apart, but he said the intake could have been placed on a diff wall if wanted.
I asked if it would be best to add a weather guard over the intake...he said "No..leave it open"

[wdfifteen]

Originally Posted by MRM

If the prior owners replaced an old gas water heater with the current electric water heater it might be left over from then. If it is filled with insulation it sounds like it was an old vent or air intake that isn't being used anymore. If it is still open and air is flowing it was meant to ventilate or exhaust something current because if they removed something that used to use it they would have sealed it because they wouldn't have wanted uncontrolled air coming into the house. Is there a whole house air exchange in the utility room?

They "sealed" it by stuffing fiberglass insulation in the hole and stapling insulation to the band board inside. The utility room is under the house, about 12'x20' and opens onto a two car garage. There is no formal way of mixing house air with the garage/utility room air. The house was built in 1972 and extensively remodeled in 2002. I'm guessing this is something left over from when the house was built.

[dad911]

From pics, it looks low to ground, second course of brick. You would never vent or intake furnace air below possible snow. Sometimes natural gas meters used to be mounted inside the basement, with a vent outside, but I've never seen them in plastic, I've only seen metal.

Not a vac intake, they would be in the rooms. Some installations duct the outlet through a muffler to the outside, and it's typically 2" pvc pipe.



In any event, unsolved mystery. Toss it, don't look back......

[cabmandone]

Originally Posted by Zeke

Vacuum intake? You maybe should go back and look how a vacuum works.

Ah c'mon man... cut me some slack! I was in between thoughts with people talking about Furnace vent (High E depending on size would use a 2" CPVC intake and exhaust) and central vac.

[cabmandone]

Originally Posted by wdfifteen

The furnace room opens into the garage. Its a big space. Anyway, it's a brand new furnace with piped in combustion air. The first furnace in the house (built in 1971) would have needed combustion air, but it's only a 2" hole. That's not much air.

For some reason I thought in one of the pics you posted that the old furnace was a two pipe system. High E furnaces could us a one pipe system with fresh air intake being drawn from the space. Someone could have poked the hole to allow air into the space so the furnace didn't draw negative pressure on the room. If your water heater was in the same room and wasn't high efficiency they very well could have added that 2" hole to allow for fresh air intake so the furnace wouldn't suck the pilot light out on the water heater.