Sleeping on a warm, heated brick bed during the coldest days of winter was certainly cozy, but there was one extremely tedious chore that came with it: after a while, you had to dismantle the bed and rebuild it completely.
This was, first, to prevent the surface of the bed from collapsing in the winter, and second, to clear out the ash from the flue. If you didn't, it wouldn't burn efficiently once winter set in, failing to heat the bed or warm the room and wasting a lot of firewood.
Besides, the adobe bricks from the bed's surface were a treasure in themselves.
The soot-blackened, acrid bricks were broken into pieces, and along with the black soot from the flue, thrown into the manure pit to soak and dissolve. This created top-grade farm fertilizer.
In fact, the soil for the vegetable garden at Shen Weimin's new house had been enriched by collecting the black adobe bricks from a dismantled old house and its old heated bed, crushing them, and spreading them as fertilizer.
