Currently, I have a 3D printer in my office where I work with a removeable vent that I fit to the window. I'm looking to move it into my basement.
I'm getting an oil tank removed, and with it, I think the crew removing it intends to cut and cap the vent and fill lines that go through a concrete wall to outside the house.
I'm wondering if it makes any sense (or is incredibly stupid for some reason) to let them close the fill line (assuming it's gnarly in there) and throw a filter screen over the vent line (since I assume it'll be cleaner (or more easily cleanable) and attach my current in-line fan to the vent.
I can then basically re-create my window setup, but connecting the 3d printing enclosure to the fan (mounted to the vent) with the goal to vent the 3d printer outside without any fresh cuts in the concrete.
What I want to ask is the following basic questions:
- Can the oil vent pipe be used as a fan-powered exhaust for a small 3×3 enclosure
- Does having an exhaust in a room with a propane furnace and a heat pump hot water heater possibly cause CO issues? I've read that having negative pressure out of a room with a gas appliance can cause CO buildup, but I don't have an easy way to vent fresh air into the room.
The propane furnace IS set up with a fresh air intake and exhaust, and there's some kind of fresh air pipe in the corner of the room.
Best Answer
I doubt the vent is much less or more grotty than the fill pipe. The fill pipe may even be cleaner, since oil washed the accumulated crud in it down into the tank regularly, while the vent just sat there and got cruddy.
Major likely issue is needing a different fan, because such pipes are quite small diameter and will cause high back-pressure when used as an air vent. A pipe half the diameter is 1/4 the area, if you have 3" vent and 1.5 inch pipe. If you have a 4" vent pipe 1.5 inch pipe would be 1/7th the area.
A squirrel cage blower deals well with high back pressure, an axial fan much less so, and a mixed flow axial blower lands somewhere in-between. Typical computer fans are axial. I could interpret your drawing as possibly a mixed flow axial, but you didn't specify fan type or duct and pipe sizes, so it's all rather hand-wavy.
You could either sort out what, exactly, is going on with "some kind of fresh air pipe in the corner" which might have been there to provide fresh air for the old oil burner, or you could clean out both pipes (lots of soap and brushes) and do a sealed ventilation with intake and outflow one per pipe. If the fresh air intake is open and functioning, you might want to use both old oil pipes as exhaust vents for the printer, given that pipes are quite small compared to even small ducts. You could run an intake over to the corner with the fresh air intake.