I am warmed by the memory of furnaces past

The living-room thermometer has slipped to 45 degrees F. in the three days since the boiler of my furnace ruptured. That first night I had arrived home from work to a cold house and water pooling on the basement floor. Thanks to superior insulation added six years ago, the house remains 15 degrees warmer than the outdoor temperature, so at least the water pipes are not in danger of freezing. Apparently others in my area of Maryland also own 50-year-old furnaces, because the valiant workers of Peterson Pump and Plumbing labored until 10 p.m. several nights this week to help all of us.

As I huddle over an emergency electric heater and wait my turn, my mind drifts back to furnaces I've known.

As a daddy's girl in the early 1950s, I spent a great deal of time with my father in thrall to furnaces. The old furnace in our four-level Victorian home in Ohio was a demonic thing that filled a large basement room. It required frequent tinkering even after Dad converted it from coal to the more efficient natural gas. I would crouch behind him as he fussed with it, peering around at the ugly, hissing beast in the pale shifting light of a bare bulb.

Defying cold winds and winter storms, that furnace heated its inner sanctum so thoroughly that my mother would send me straight to the basement in my drenched snow pants and wool sweater. If alone, I dashed past the sizzling machine to the clothesline strung in the abandoned coal room. When Dad accompanied me, it wasn't so scary. After he helped me hang the clothes, we would pass a peaceful hour before dinner in his cozy workshop across the hall as he repaired a broken lamp or chair, and I nailed pieces of wood into makeshift boats for the bathtub.

My grandparents' house near Lake Erie was heated by a different type of furnace: one that burned coal. Every Sunday visit included a strange ritual when the men excused themselves after dinner to "go see the furnace." With me shadowing Dad (partly to avoid kitchen duty), we wound down the dimly lit staircase to the netherworld.

Past the stacked Christmas decorations and dusty tree stand, past the new Dexter washing machine with its white porcelain tub and gyrator agitator, past cobweb-draped boxes of farming and hunting relics 70-plus years old, lay the furnace room. One more grimy turn and we entered the dark domain of a seething, spitting beast.

Intrigued and frightened by this fiery fiend, I cowered behind Dad as the men examined and discussed its every inch. They prodded its vast belching belly, poked at its fantastic metal arms twisting up through the ceiling, and finally pried open the mighty maw of the burn chamber itself. Crackling red flames burst forth in a shimmering mirage that could have inspired the underworld's Balrog of J.R.R. Tolkien's "The Lord of the Rings."

To my horror, Grandpa reached inside with a long iron tool and raked the glowing coals. Red and black sprays attacked his coveralls as he poured ash into a fireproof metal bucket. Then he shoveled in several loads of coal, spreading the lumps evenly in the intense heat.

I cowered against the wall, mystified by the lure this monster held for the men of my family. But I was also fascinated by their conversation about circulating radiators, the superiority of coal over wood, the costs of various fuels, and the merits of insulation.

As the installers finish their work on my new furnace, I smile, reflecting on how awed Dad and Grandpa would be with this tiny, tidy box of a furnace, merely 15 inches across, two feet long, and barely 30 inches tall. Thanks to new technology, this docile unit burns natural gas much more efficiently than my forebears could have imagined. It generates, Mr. Peterson says, 100,000 BTUs of energy. Its convection system heats our home effortlessly and cleanly, with neither coal dust to inhale nor clinkers to remove.

For my part, it's nice being toasty warm again as I enjoy both this convenience of modern invention and the memories that help me appreciate it.