Hello! I am looking for advise on winterizing an oil fired hot water boiler. While I don't intend to shut down the system completely, I would like to keep it as low as practical. The house is in a rural area of Pa. so there is also the chance of an occasional power failure. I think I have a pretty good handle on the winterization of the boiler itself, but the domestic hot water supply also comes off the boiler, and here is where I am unsure of what to do . I know that I can't put boiler anti-freeze in that zone. Any help would be appreciated. Thanks!

Isolate and drain that part of the system. To make sure it is completely drained use compressed air to blow out any residual.