How To Keep Pipes From Freezing
When water freezes, it expands as it cools. If the water is contained in a metal pipe, the force of the expanding ice can crack the pipe. Then, when the ice eventually melts, water will pour from the crack. If you live in a climate that has below freezing temperatures, you must take precautions to make sure that none of the pipes in your home will freeze. Note that this is not likely to be a problem with plastic pipe, since the plastic stretches when the ice expands. On the other hand, metal contracts with cold, so that the combination of expanding ice and contracting metal can cause cracks at only a few degrees below 32 degrees Fahrenheit--the freezing point of water.
To prevent a pipe from freezing, simply make sure that there is no water in any pipe that may be exposed to temperatures below 32 degrees Fahrenheit. If you are living in a house and maintaining a comfortable temperature there, all indoor plumbing is safely above the freezing point at all times. Your only concern is with outside faucets that are used, for example, to connect garden hoses to the water supply. The water in the pipe leading to an outside faucet can freeze, and the ice can extend in the pipe to a point inside the house.
To drain the water from a pipe leading to an outside faucet, first shut off the flow of water in the pipe by turning the control valve shut. The control valve is on the same pipe but inside the house. The wheel on the control valve is turned clockwise to shut off the flow of water. Now the outside faucet is opened fully and the water should flow out, because the pipe leading to the faucet should be tilted downward toward the outside. The control valve should have a drainage screw cap on the faucet side of the valve, and it also should be opened. This ensures complete drainage even if the pipe is not tilted correctly.
After the water has run out of the pipe, the handle of the outside faucet should be turned slightly so that it will not be fully opened, and it should be left open all winter. In the spring, the outside faucet is closed, the drainage screw cap is closed, and the control valve is opened.
If it is necessary to have water available outside the house during winter, your home should have an antifreeze faucet. A long rod to the valve inside the house connects the handle of the outside faucet. When the faucet is turned off, it closes this valve, and any water left in the pipe between the valve and the outside simply flows out of the faucet because of the downward tilt of the pipe. If your outside faucets are of this type, you don’t have to worry about freezing pipes.
If you are leaving the house empty for any period of time, you have to be concerned about indoor pipes freezing as well as outside faucets.
For short periods, such as a two-week vacation, you should leave the heat turned on low to keep the house at a temperature above freezing. The fuel cost is small compared to the trouble of draining all the water pipes.
For long periods, such as when closing a summer cottage for the winter, you must drain all the water from the plumbing and heating systems. Remember that during the winter, the temperature inside an unheated house is not very different from the outside temperature.
To drain the plumbing, first make sure that the main supply valve is closed. The water main is below the frost line so that you don’t have to worry about that freezing.
Now open all faucets in the house. This will drain all the water to the level of the lowest point in the water system, and this can now be opened to remove the remaining water. If there is no drain outlet in your system, you have to disconnect the supply pipe at its lowest point, which is usually at the main supply valve. If any pipes have loops or upward tilts, you must make certain that they are emptied. You should disconnect the section of pipe and pour out the water.
Water must be removed from all traps in drains. The purpose of a trap is to provide a water seal to prevent sewer gases from entering the house. Under normal use, the trap is filled with water.
To empty the trap, loosen the two large nuts with a monkey wrench, remove the trap completely, and pour out the water. Then connect the trap again and fill it with a liquid that won’t freeze, such as antifreeze. However, do not use alcohol or any other liquid that will evaporate before you reopen the house. About a quart of liquid is necessary for each trap in the house. Some traps have a nut at the bottom. To empty this type, it is only necessary to remove the nut and let the water drain out.
Water must be removed from all tanks, including toilet tanks and boilers. Each toilet should be flushed, and then the last half-inch or so of water in the tank removed with a sponge.
Boilers usually have a drain spigot at their lowest points.
Toilet traps must also be emptied. You can drive out much of the water with your force cup, but you may have to use a syringe to remove the rest. Refill each toilet trap with about two quarts of antifreeze.
Don’t forget to empty the water from traps in the floor drains in the laundry room, cellar, or garage, if you have any, and to refill with antifreeze.
If the house uses steam for heating you will have to make sure that the radiators are drained.
To prevent water from being held in the radiators by air pressure, you must remove an air valve from one of the radiators on a top floor. This will release the water in all the radiators so that it flows back to the boiler where it can be drained off.
Don’t forget to put back the valve before starting the heating systems again in the spring.