If for some reason the power fails during freezing weather follow these steps to reduce or eliminate damage to the pool:
Turn off the breakers to the pool equipment
Open the air bleed on the filter (if frozen pour warm water over it to help free it up)
Remove the drain plugs for the the pumps and the filter and put them in a safe place (I put them back into the pump basket)
Remove the heater plugs or open the heater valves
Put all 3 way valves into the all open position to allow water to flow freely between and back into the pool.
To prevent skimmer damage put a one-liter bottle half filled with anti-freeze into the skimmer, this will help prevent expansion.
Any pipes that cannot be drained need to be wrapped with electrical heat strips available at any hardware store.