Testing Hardware – QA and the Nest Thermostat 

I have had a Nest thermostat now for 3 years. For the first year it was great. Then, something shorted out in our furnace or something and it went haywire. 

Problem was, the furnace blower would try to start when the A/C was on. Not good.

A bug fix was to just disconnect the heat wire during the summer. But I am getting sick of that. 

  
And how can I prove that it isn’t a botched wire job or a screwed up Nest?

Most HVAC companies still don’t know much about Nest and that’s a shame, but their first line of defense would be to blame the Nest anyways.

Tonight I ran and picked up a $25 programmable thermostat and wired it up. All wires. To try to replicate the problem 

Well I hook it up and no problems. My guess is the Nest is borked. Now on to try to prove that.

In any event here is my test harness 🙂

  
So now the question is. Try to get it fixed/replaced or just buy a new one. After I get it sorted I will update this post.