I'm guessing you mean for under the pot and not in it because they are not waterproof. I don't thing they have enough watts to do much for heating, they are only 500w.
I read somewhere that you should not solder or splice the wires because it changes the resistance of the wire. I ended up buying longer ones for my Love controllers.
I found a scrap yard that had 500+ kegs and they were getting ready to chop them up for scrap. I bought 30 of them for $10 each and then told the owner of our LHBS about them. He bought the rest and is now selling them for $70 each.... If I had the money and the storage area for them I would...
I'm guessing if there is no access to brewing supplies pools will be scarce also. I helped brew beer in Kuwait and it was not even worth the trouble because of the lack of good fresh ingredients.
All new mini fridges have the lines on the sides. They are always touching the skin so if you cut a hole in the plastic on the inside and stick your finger through the foam you can locate them easily.
That is an interesting idea, I just don't know how much business you will get, after someone rents once they will most likely build/buy their own. A BOP is probably a more viable option so you can teach people at the same time.
An electrician will be able to help you get 120/240v power over to your brewery with no problem but you need the automation part in a schematic for them to understand what you are doing.
Yes, they are pool filter housings. When I get them they look like crap and it takes a lot of work to clean them up and convert them but you can't beat the price. I pay $30 for the pot and about $30 to have the couplings welded on if I pre-drill them first.
They are 240V 20A plugs. Who would use a 7A plug on a heating element?
They are about $2 each and are letter "H" on this page...
http://www.mouser.com/catalogviewer.aspx?page=1312&highlight=161-PX0596%2f63&catalogculture=en-US&catalog=645
Chlorine won't give you headaches but it will make the beer taste like band aids. What you had was fusel alcohol from fermenting warm, it will give you nasty headaches after just a couple beers.