With the temperatures consistently dipping below freezing this season make sure your hose bibs are protected.
If you have an interior cut off, make sure that is in the off position and then bleed the remaining water from the lines so it doesn't freeze. If you do not have a seperate cut off for the hose bibs, make sure you do not have any hoses connected. The hose will hold water in the spicket itself which could freeze, expand and comprimise the copper line.
Don't forget to replace air filters on a regular basis as well.
Stay warm this winter!