Is there a way to identify bad connections that are still connected but are prone to overheating (loose screw, badly applied wire nut, etc)?
I just moved in a newly built house and started to wonder if those kind of things could be identified or perceived before some outlet start melting due to a loose wire somewhere in the circuit.
PS: I'm not expecting it to happen. Neither I think that the electrical was poorly done, but I've seen that happen more than once in properly done wiring...
The only way I would know how to do it is to go and buy an inexpensive Infrared Thermometer. You can buy them anywhere for less than $60.00. Then you can walk through and "site" any device that appear to be warmer than normal. Start with you panel and survey every breaker. Then you can go to every device and check it. Did I mention you should make sure the circuit is on a load for at least an hour. I would use a small 1500W heater for a load source on receptacles. This is something you can do over time. If you are just shooting a receptacle head or an AC disconnect the temperature should rise to at least 5 - 10 degrees above normal temp. Really loose connections will rise much more than that.
There are circuit breakers specifically designed to detect the conditions you are talking about. They contain a small digital signal processor that listens for the telltale sound of arcing. I talk like it's a sound, it really is - if you've ever had a loose connection on a speaker or headphone, you've heard it.
They are called AFCI breakers.
I imagine in a new build, your panel isn't CH, QO, or an obsolete panel like Pushmatic... so the AFCI breakers shouldn't be too expensive, probably in the $30 range.
If the house is super new, there's a good chance some of your breakers are already AFCI.
This won't hunt down the fault, but it will prevent it from burning your house down. when you get a trip, then you take apart each (now dead) outlet and look for trouble. There's no realistic way to find them in advance as they can develop over time.
If the breaker slot is already occupied by a GFCI breaker, you can either use a combo AFCI/GFCI breaker, or relocate the GFCI function downline to the first receptacle. Unfortunately AFCI receptacles are not common.
All my panels are the kinds where GFCI breakers are prohibitively priced, so I am fond of sticking a junction box 6 inches away from the panel and sticking GFCI receptacles there, then feed the LOAD wires back into the service panel to serve the circuit I'm protecting.
