Trying to beat the heat.

If you don't live in Texas you may have missed the horrible terrible sweltering lovely weather we've been having. I can't remember the last day that it didn't get over 100°F. Yeesh.

So with the utility bill soaring like Icarus, we decided something had to be done. We have a large front window that is great for natural lighting.  It also gets pretty full afternoon sun so it was really heating up the living room.  We bought thermal curtains for that window and we also replaced the thermostat.  Here's the original thermostat.

I think the technology behind these was invented in 1950. It wasn't very accurate and the a/c always seemed to be running without end, which coincidentally sounded like money being siphoned out of my wallet. So I bought a digital programmable thermostat and replaced it.

The thermometer is housed in the front piece. It's a spiraled piece of metal that will expand and contract with the temperature. As it increases the metal expands and swings to the right. Assuming it's calibrated, expansion and contraction of metal is a fairly constant calculation.

Here's the temperature set mechanism. The left lever sets whether it's auto or constant and the right lever sets whether you're heating, cooling or off.  The bottom lever lines up with the thermometer on the front (so you can see what you're setting it to) and changes the tilt of the mercury bulb at the top. As the temperature increases, the mercury expands and moves across the bulb, completing the open circuit. It's actually pretty clever. But again this is all assuming it's calibrated correctly. And as I found out removing it, the bottom screw anchoring the unit to the wall was not actually holding anything. This meant that the whole thing could swing which invalidates the pitch of the mercury bulb. This explains why sometimes I would smack it and the a/c would come on or go off. Lovely.














But never fear, I pulled that dinosaur off the wall and installed the new one. It's pretty. Ignore the now-exposed unpainted portion of my wall back there.

And look, it lights up! ooooh. aaaaah.

Here's hoping that, like Icarus, the energy bill will also plummet back to Earth.


********update************

I just realized that the mechanism of the old thermostat would have to work in reverse for heating the house.  The heat would stay on unless it was warm enough to cause the mercury to expand and complete the circuit, at which point it would cut off.