Unter Dog

I work as an electronics engineer in heavy duty off road . My company has 100's of thermal chambers, and I can off the record explain what we use and why. Most of these chambers run 24-7. You probably don't need someone who's base is centered mostly around ruggedizing electronics, but definitely can answer any questions on the side.

I'd generally worry about your electrolytic caps, as at higher temperature you can generally say 10 C lower doubles lifespan. I'd assume you'd get an acceptable lifespan out of your silicon and caps if you are running 85C max and 75-80C normally with a normal consumer load cycle. Note a year is 8760 hours. Note caps are generally rated in hours at their max ripple current at a specific temp. https://www.xppower.com/Blog/Electrolytic-Capacitor-Lifetime-in-Power-Supplies (there are a ton of articles online like this i just grabbed one quick). Electrolytic caps many times are the weak link in a system. I design high reliability electronics for harsh environments and for most components higher temperature lowers life (things like NAND flash have caveats) but at what point does it not matter anymore which can only be answered by you. Electomigration is a common failure mode https://www.sciencedirect.com/topics/materials-science/electromigration for silicon for time at temp. Read up if you are interested. One also thing to note is the rate at which things change temp also affects reliability as coefficient of thermal expansion differences can cause long term failures like solder joint cracks and internal part delamination as stress/strain occur when parts expand/contract at different rates.

We only use de-ionized water for our flux cleaning process. For manual cleaning we supply our techs 99% isopropyl. Tap water can contain a lot of crap you don't want left on your PCB.

I dislike my Neato. It scratches wood floors when it’s silicone brush gets full of hair/dirt.

Is this for a 12 volt automotive system like a car?

You could also use a zener/bjt combo for a poor mans regulator. An in-line LDO would work also.

Add a comparator with small hysteresis controlling a FET. Requires designing it though.

14" blade