I live in the Portland area and never winterize .. but I have 110 avail, dump the water tank and leave my agua hot on electric at the lowest temp .. 40. since you dont have electric that changes things most of the year nothing would be needed. We. camp in virtually every month. However Portland does have a week or two that it can get down below 20 and not above freezing. This year there was no need. In the past I have bitten the bullet and winterized using the blow out method dumping the water tank and HW heater when I had one. Your only other choice is to watch the weather and turn on the furnace those few days.. Short 20deg nights and warming above freezing days (normal) I have done nothing but I wouldn't take the risk esp if you arent close by to tend to it in a hurry.
