I usually wear a sweat band all summer long and keep them in the truck. A few weeks back, was out of the paste & and the spray on gell ( which is very handy to use but expensive)and no spare cloth. Well the sweat band is very versatile for the brazing. Loop one end over the valve cover and around the valve and back over the cover. Works great. Was handy using it at the air handler too to protect the the expansion valve sensor (Rheem likes to wrap theirs like Fort Knox).
Just wanted to pass that on. I've been brazing with the cheapest stuff on the market for over 20 years. PhosCopper 0% by Harris. It works. And a couple of years back, Copeland cast their approval of it, so that sealed the deal, finally. Anyone else out there use it?