said by norbert26:year round . A few rooms can be heated by the gas stove / portable propane heater(s). Some rooms would be closed off .
Well, I googled a bit and there aren't real solutions to your problem, only PREVENTION tricks for short power outages, or just general usage.
However when I googled about draining those systems, it seems to be a yearly maintenance thing, so I guess doing that would prevent the pipes to freeze.
Next time, get a generator to hook up to your panel and you'll have a lot more comfort