Tuesday, September 12, 2023

Digging a Hole Where the Furnace Gets In

Kindly forgive the Beatles song stretch. Today is a brief post covering a considerable amount of sweat and effort: getting the furnace moved into the crawlspace.

Can You Dig It?
dig hole
In my last post, we cut a hole in the old kitchen floor just inside the door to the garage. The hole is one floor joist wide, allowing the most narrow dimension of the furnace (~11cm or just over 14inches) to pass through. We decided that the height (depth?) of the other side of the hole would be the largest of the 2 remaining dimensions of the furnace. We could have used the next-smallest. We figured that whichever dimension remained would need to be available between the bottom of the floor joist and the ground. Since the plastic-sheet covered dirt floor was 2 feet (60cm) +/- from the bottom of the joist, we would need to dig. The furnace has one side that's about 28-1/2 inches (72cm) and it stands 33-1/2 (85cm) tall in it's original alignment. Our choice was to dig down 4 inches or so for the size of the hole or dig down almost a foot (25cm plus wiggle room). I suppose the mount of dirt to move is the same, its just a question of depth versus width. Still, it just seemed like digging shallow and wide felt like less dirt.

With the hole cut in the floor, I grabbed a 5 gallon bucket and the post-hole digger. I filled a bucket, hauled it up and outside and spread the dirt around a low spot on our lawn. I did that at least a dozen times. Once the main rectangle was dug, I considered that once the furnace was in the hole, we needed to tip it one way or the other to get it flat so it could slide around. So, the edge of the rectangle that faced towards the furnace final destination was cut down on an angle so we could pull that bottom edge up and away from the hole. I figured that if I had 28 inches from the bottom of the hole to the top of the dirt as measured from the inner edge of that floor joist, it could effectively hinge. By the nature of how this tip, though, that front edge will come up between the joists and not have an issue. It wasn't until after completing the dig, that I pieced that together and determined that I dug out more than I needed to. Ultimately, it is better to have too much room than not enough.

Venting Some Venting
venting set aside
With direct access into the crawlspace, Boo and I looked towards the location where the furnace would ultimately reside. Our view was impeded by supply venting routed all over. There are 2 main runs, heading in opposite directions: one towards the hole we just dug and the other going away. From these main trunk vents, the smaller round vents are attached. Where the 2 main runs come together is a large box (plenum?) where the conditioned air leaves the furnace and enters the system. All of this stuff needed to get shifted out of the way before we could bring the furnace down.

We started with the vent that ran from the box towards the hole. This system is old, and held together mostly by faith and tape. Boo removed the tape at the box, and the vent detached easily. She cut down the cloth webbing that suspended the vent from the floor joists and the whole thing dropped to the floor. She slid it to the side. I followed suit, removing the vent running the other way by the same steps. This left the big box.

the box
The box was simply hung from the floor by a lip that was less than 1/2". I lifted the edge of the lip with a bladed screwdriver, pressing the lip up and inward while sliding the screwdriver along the edge. The lip simply folded under the floor. Once the final side of the box's lip was so treated, the box fell to the floor of the crawlspace. I was (and still am) amazed that a heat system constructed in the late 1940's was held together without any fasteners. I removed the connectors attached to the box that allowed the vents to connect and then lifted the box out through the hole.

blocked with soot
The last thing I tried to complete before lowering the furnace was removing all the soot from the clear-out. I foolishly thought that I could dig out the soot that was at the clear out down in the crawlspace. Well, it looked like the clear out had maybe never been cleared out. I was able to remove a full trashbag of soot and was unable to reach any further up into the chimney. Looking down from above (through the original oil? wood? coal? furnace-to-chimney access, I could tell there was at least another foot of solid soot I could not reach. So, Boo and I decided that we would bring in a professional. Many years ago, I had used British Brush to clean and repair chimneys at various houses. Well, they are out of business so we hit Yelp / the Yellow pages and solicited bids. In the end, we have some chimney repair from when the furnace was in the dining room, probably a new liner from the cap to the clear-out and then a safe connection to which we can attach the furnace. My biggest concern about this whole furnace move was to safely manage the exhaust and not accidentally create a CO or CO2 issue inside the house. Having a professional will help.

This is where we are left off. We have the venting removed, the furnace freed, an access hatch built and the hole dug for moving the furnace. We decided to leave everything just like this until after the chimney folks do their thing so they have the greatest mobility. We have some family events coming up, so the work needed to come to a stand-still anyway. We will pick this up after that.

As always, thanks for following along-

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