Okay so the title kinda spills it but I'll tell the story all the same. TLDR at the bottom.

This story actually did happen today, actually just a little while ago, so the shame is still deep in my heart. It starts this morning while I was attempting to adjust the temperature in my house and my thermostat just up and dies. I tried to fix it but it's done for. No heat or A/C until it's fixed and since this is south Texas we kind of needed both today. But I'm relatively handy so we'll just buy a new one and fix this.

We end up spending the day out just doing family stuff and along the way I pick up a new thermostat. I opted for a fancy wifi enabled smart device type thing that not only looks cool but can apparently read my mind and make sure the house is always at the proper temperature. I have some doubts about its telepathic powers but it looks cool so I bought it.

We got home around dinner and I get straight to work. First things first I watch a video online on how to install it. Unfortunately my house has older wiring so there are some extra steps but it seems easy enough. I decide to head up to the attic to install the first part. This ends up requiring my wife's help due to small spaces but she's good with tools and able to squeeze into the space required so we get that wired up pretty quickly. Next we head back downstairs to wire up and install the actual thermostat which goes really quickly and we're ready to flip the breaker on and......nothing. Just nothing.

The next hour is spent rechecking and rewiring everything we've just done. There are 10,000 trips up and down the stairs. My hand starts getting chafed from the number of times I've flipped the breaker on and off to check things. My brother in law, who's a general contractor in another state, is called and consulted. He has interesting but ultimately not helpful thoughts. Finally I cave and call my HVAC guy. Thank you Jesus he's nearby and although on his way somewhere he'll u-turn and come see me real quick.

My guy, we'll call him Saul, finally pulls up. It's late, I'm tired, and everybody is miserable. But Saul is an HVAC genius who's been bailing me out for 15 years so we're good. I explain to Saul what's going on and we head inside. He does a quick check over of the thermostat, wiring seems okay, but there's no power running to it. He heads up to the attic. It's not even 10 seconds later and "hey, did you try closing this door switch before you powered it on or no?"

My jaw drops....the door switch.

Now for the uninitiated the door switch is a switch that cuts power the furnace when the side panel is opened. It's a safety thing so you're not in there working on live electrical parts. I'm familiar with the overall concept but hadn't considered that my furnace had one. I'd also left the panel wide open the whole time because I never close stuff back up until I'm sure my work is good. It's kind of a bad habit.

He pushes the switch in and everything comes to life. So now the problem is fixed but I'm definitely an idiot. Saul calls down that he'll check over my wiring real quick before he closes everything up. I'm hoping he takes his time so that I can come up with something good to tell my wife. That hope is dashed about 20 seconds later when I hear my wife from the other room: "Hey (big brother), it was the door switch. He needed to put the side panel back on first." There may or may not have been laughing IRL but there definitely was in my head. Saul comes down from the attic and announces it all looks good. I sheepishly ask how much and he declines payment. "I'll just tack it on the next time you have a problem." It's generous of him and eases the sting a bit. I see Saul out, put away my tools, and slink off to my office to eat a cold dinner and share my shame online.

TLDR: Replaced house thermostat. Didn't work. Ended up calling professional who shows up and points out that there's a switch on the furnace that needs to be closed in order for it to get power. Much shame for missing little thing.