During plumbing emergencies, the first step is to stop the flow of water immediately. Do this by turning off the main water shutoff valve or the shutoff valve for the particular fixture or appliance. You and each member of your family should know the location of these shutoff valves.
Locating the main water shutoff valve is discussed this link. Shutoff valves for fixtures and appliances can usually be found underneath sinks and toilets and behind clothes washers, water heaters and other appliances.
If the emergency is limited to a specific appliance or fixture, look for its shutoff valve and close the valve by turning clockwise. Turn off the main shutoff valve if the problem is a leaking pipe or if there is no shutoff valve for the particular fixture or appliance.
If a pipe leaks or breaks or if a joint should loosen, turn off the main shutoff valve to prevent water damage. If you turn off the main water supply, turn off your hot water heater by turning off the circuit breakers and the gas supply to the hot water heater. Failure to do so can cause the hot water heater to overheat, damage the heating elements and injure anyone who unknowingly turns on a hot water faucet.
Next, call a plumber or make temporary repairs yourself to stop the leak. Have the pipe replaced or the joint resoldered when it is convenient for a professional plumber to do so.
If your washing machine, dishwasher or other water-using appliance appears to leak, first check to see that the trap through which the appliance drains is completely open. Sometimes a partially-clogged drain can cause an overflow within the appliance. If the drain is clear, consult the appropriate appliance repair person.
Pipe insulation and freeze-resistant outside faucets are available to reduce the risk of freezing. Even with these products, problems can still occur.
If a pipe should freeze, thaw the pipe slowly with a hair dryer or towels soaked in hot water. Heating the pipe slowly may prevent the pipe from breaking. Do not heat the pipe with a torch. This has been the cause of many fires.
To prevent frozen pipes, drain water from outdoor faucets and pipes, remove and store outdoor hoses and never leave your home unheated during cold weather.
When the drain pipe from a tub, sink, shower or water-using appliance becomes clogged, turn off the faucet or appliance that flows into the drain.
Next, try to remove the obstruction with a rubber plunger. The rubber cup of the plunger should cover the drain opening and the water should come well up over the edge of the cup. Work the plunger up and down rhythmically 10 to 20 times in succession to build up pressure in the pipe. This does more good than sporadic plunges.
If the plunger does not work, call a plumber. Do not attempt using a snake or other tools. They can damage expensive fixtures. Never use drain cleaner to open a totally clogged drain. It will mix with the water to form a caustic solution.
If a toilet overflows, stop the water flow by reaching inside the toilet tank and pushing the tank stopper down into its valve seat. Hold until the tank fills and the water stops. Next, turn off the shutoff valve underneath the toilet or turn off the main water shutoff valve. Unclog the toilet.
A clogged toilet should be treated almost the same as a clogged drain. The trap is built into the toilet and is therefore less accessible. Try to unclog the drain with a plunger. If that does not work, call a plumber.
If a faucet wont shut off, turn off the water at the shutoff valve underneath the sink immediately. If there is no valve, turn off the main water supply shutoff valve. Call a plumber or repair the faucet yourself. There are a number of plumbing repair books on the market for do-it-yourselfers.
You should not attempt to repair cartridge faucets yourself. These faucets are exceptionally advanced and quite expensive. Call a professional plumber if you have any problems with a cartridge faucet.
If steaming water flows from a hot water faucet, do not touch the hot water faucet. Leave the faucet running. Turn off the electricity or gas supply to the hot water heater. Let the faucet run until cold water flows from the faucet (the water in the hot water heater is no longer overheated), then call a plumbing professional to repair the faucet or the hot water heaters thermostat .