Why do you want to drain the boiler? Because of the rusty water. You should
only drain the boiler for repair work that requires draining. New water will
introduce fresh oxygen that will create new rust further corroding the
metal. Old rusty water has used up the oxygen and no longer corrodes.

"New & Improved - N/F John" wrote in message
news:zlRoj.831$Ou1.39@trnddc07...
What do you think of trying to capture the rust in the boiler by placing a
strong permanent magnet near the boiler drain? Remove the magnet and then
drain.

John