Keeping pipes from freezing is rarely a concern in most parts of the world, and you certainly don't need to turn up the furnace to "comfort levels" to do it.

Keeping pipes from freezing is rarely a concern in most parts of the world, and you certainly don't need to turn up the furnace to "comfort levels" to do it. 10 C / 50 F is more than sufficient with adequate safety margins, but many people will complain about being uncomfortable at those temperatures. That's where directional space heaters come in.