Back upstairs to the window project. With some prying and some sawzall work on the nails and caulk, we removed the window, frame and all. It was already in the 40s and with this huge hole in the side of our house where once there was a window, things were cooling off rapidly in there. Erika stapled up some plastic to keep the wind out.
The replacement window is a good deal smaller than the original window, so we knew that we would need to frame in the rough opening a bit. We measured up the replacement window and rough opening and split the work: Erika took to assembling the vertical framing members and I took to the horizontal.
It felt good to be doing something that we know how to do (and, we couldn't have said that 6 or 7 months ago). No instructions, and barely any pausing. One two three, we were nailing in our frame and trying to fit the window in place. We did have to trim about 5/16 of an inch off the bottom spacers but after that, the window went in, we leveled and plumbed it, and nailed it in place. Done. Well, for the night. We need to caulk it up and trim it out, but that's nothin'.
Erika also stapled some plastic to the outside of the house, over the (basically non-existent) bathroom window that we're about to replace, and also hung a wool blanket over the inside of it. At least now the bathroom isn't 20 degrees colder than the rest of the house!
Before calling it a night, we went outside to check on the furnace, which we planned to just let burn out since we couldn't circulate that heat through the house. Since we had the circulating pump for the furnace turned off, the furnace had reached a very high temp and shut itself down. It brought to light something I hadn't noticed in the manual, and that's that the high/low setting is controlled by one box with two dials, and what I thought was the high temperature aquastat is actually a high temperature safety cutoff aquastat. Good to know. We turned its pump back on and cooled the water a bit. It returned to a normal temp and restored power to itself and we let it burn out.
Now, to figure out what's going on with the rest of the system...