Get a "shop light" and position it near your vulnerable pipes and keep the bulb on. The heat from the incandescent bulb may raise the surrounding air temperature to above-freezing, protecting your pipes. We do this with our water wells in the Yreka, California area, where it never really snows but they sure get a lot of "Shasta dandruff" piling up during surprise winter storms. And people blame Thomas Edison for inventing "wasteful" bulbs that release too much heat!