Q:

How can I add "smart" functionality to an old thermostat?

I recently moved to an apartment, and my roommate and I were talking about how much better it would be if we had a smart thermostat. We're going to ask the landlord about an upgrade, but I thought I remembered seeing systems somewhere that allowed you to smart-ify a traditional thermostat (very technical term, I know). It's one of the ones with just an up and a down button, nothing else.

A:

Devices exist which are basically heaters with timers, which can be mounted under a traditional thermostat to bias it toward turning the heat off sooner. By juggling the two settings, this can be made to work somewhat like a setback thermostat.
Mostly obsolete, since not very efficient, but useful in cases where the owner forbids installing a real smart thermostat.

