Prepare for high heat. The hot closed-loop exchange pipes between the collectors and the solar storage tank call for special insulation that can withstand high temperatures. Ordinary foam insulation sleeves are not designed to hold up against the higher temperatures produced by solar collectors. UV-resistant rubber pipe insulation rated up to 220ºF works well but can be difficult to find locally. The piping coming out of the storage tanks is not subjected to the high temperatures present in the closed loop, and ordinary pipe insulation works well.