We don't often have enduring freezes in the Valley, but when we do, it's important we take important steps to make sure our pipes don't burst. Here are a few ideas:
1. Open the access hatch to your attic. This will cause you to lose heat in the home, of course, but the idea is to get heat into your attic to keep pipes warm.
2. Wrap exposed pipes in an insulating material. It does not need to be anything special. Towels and other items can work well.
3. Drain any outside piping, including hoses. My pool refill pipe runs above ground, so I unscrewed the fill valve and let the pipe drain out. If you can't drain a pipe, wrap it if possible.
4. Leave a light on (not fluorescent) in any outdoor storage areas (with pipes) that don't get heat. Light bulbs generate heat, and can keep a small area warmer than not having a bulb on. The higher the wattage of the bulb, the more heat it generates, but don't exceed the rating of the fixture.
5. Open vanities under sinks to allow heat into them.
6. Leave water dripping slightly from both the cold and hot faucets. This is my least favorite, as it wastes water, but it is effective.
7. Sprinkler lines, if buried properly, and the freeze isn't too long, might be ok. It just depends. If you have a quick and easy method of blowing out the lines, it's not a bad idea.
8. Turn up the furnace a bit. This will help keep exterior walls, the attic, and pipes warmer as well.
These steps will help. Not taking action could lead to pipes bursting. When that happens, most people call the fire department...whose people arrive in a truck filled with thousands of gallons of water. :) Good luck!