"Tic-tic-tic-tic." "Phoomph." "Gosh!"
That is what you want to hear when it's 10 below. The gosh, however could be a problem.
The tic-tic-tic is the furnace's igniter. The phoomph is when the gas catches. The gosh is the water moving through the pipes. But when the gosh turns into GOWRSH GOWRSH GOWRSH, sounding something like Goofy the Disney cartoon dog shouting in distress, well, something's amiss.
I called the furnace repair people to schedule a tuneup, and the conversation's translation goes like this:
Dispatcher: "There will be a base charge of $49.99, with the expectation that they will find a problem costing 10 times as much."
Me: "That's fine. Will the $49.99 charge be applied to the inevitable repair?"
Dispatcher: "Yes, we'll wrap that into the total charge so you don't feel like you're getting taken, but you'll have no basis for understanding the final total anyway, so it doesn't matter. Also, it's not a furnace. It's a boiler."
Me: "Thanks! See you between 5 a.m. and 4:45 p.m."

