Definitely agree with other to turn off power, drain water lines, and add antifreeze to all PVC traps. The hot water tank should be turned off BEFORE draining water.

If the lines have already frozen and burst, you may have damaged the washer and dishwasher intake switches and drain pumps if you have these. They have standing water in them that can freeze and expand. I own a camp up in Maine and have dealt with every one of these issues. Good luck. Hope you get to it before any of this happens.