Hey everyone! I'm working on rehabbing a late 1800s house and need some advice on the HVAC situation. Right now, I've got an oil-burning forced air furnace in the basement that heats the first floor, installed back in the 90s, plus an older fire-based furnace that I'm not using anymore. The chimney for the oil furnace runs up through the house and goes out through the roof, but the old wood-burning furnace's chimney is too large to remove through the basement door. There's a decent amount of space around the chimney in the finished areas because of how it was framed back in the day.
Here are my main questions:
1. Can I frame closer to the chimney because it only handles the oil exhaust now? Is there any risk?
2. Is it feasible to reroute the oil furnace's exhaust directly outside and potentially remove the chimney? I worry about the mess involved in removing such a large chimney, but I'm considering it since I might need to upgrade my heating system in the future. I would want to run new ducts for heating and cooling to the upstairs, and the chimney's current spot seems like a prime location for that.
Thanks for any guidance! I'm also planning to get some HVAC techs to quote a new system, but just looking for thoughts for now since the heating works fine for now.
3 Answers
Hey! Yeah, you might be okay with framing closer to the chimney for the oil exhaust, but definitely check your local building codes first. They can vary a lot, and it's important to ensure your chimney is safe and possibly re-lined if necessary.
As for the exhaust, you should also check your local codes on venting. It might be doable to run it outside, but consider how far away it must be from windows and how high it should be above the roof. If you're looking to remove the chimney altogether, I'd suggest just waiting until you get a clearer plan for the new furnace; it could save you a lot of hassle down the road if your plans change!
Just a heads up, you'll want to make sure your exhaust stack follows local codes. Usually, they need to extend above the roofline. And regarding the chimney stability, remember that old chimneys might not be safe—especially in the event of an earthquake or heavy weather. Have you considered heat pumps? They’ve been working out well for my neighbors!
If you have the budget, I say go for it! Removing the chimney could really open up your space. You might need to patch the roof, but the extra room could be worth it! I'd definitely recommend looking into a modern, efficient gas furnace. It’ll provide better heating and save on energy bills. Plus, venting it externally has its own challenges, but it's typically better to have it run inside if possible to avoid corrosion and condensation issues.