Hi I think you will have discussed this point before but being new to small boilers, I wondered what your opinions were as we are divided on it at BHR. With copper boilers, should you drain them fully after each running, or at the end of the season? Cheers Ken MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.