When you turn on your faucets and notice that water is sputtering or spitting out air, you have air trapped in your pipes, a condition known as an airlock. An airlock works like a restriction, lowering the water pressure and smooth flow of water in your house. Sometimes it can completely shut off the water to your faucets.
Airlock in water pipes is caused by temporarily shutting off and draining water to the house by the homeowner or the area municipality during maintenance, allowing air to enter the pipes. In a well system the problem can also be caused by other factors such as a faulty pump, pressure tank or even drought.
Whenever you are performing any form of maintenance in your plumbing system like draining the water heater, installing a new toilet or bathtub, you need to first shut off the water and drain that which is already in the pipes.
Since a vacuum cannot exist in the pipes, air will occupy the space inside the pipes. When your turn on the water flow to the house, air will be trapped at the high points in your water pipes network creating an airlock.
The best way to bleed off air trapped in your water pipes is by shutting off the water to your house and then drain the water in the pipes and fixtures by turning on all faucets, and draining all appliances. Turn the water supply back on, and let it flow through all faucets for 15 minutes. Flush all toilets and run rinse cycles on the dishwasher and washing machine.
An airlock is different from a water hammer and will not damage your plumbing system. A water hammer occurs when water flowing to a certain faucet or appliance is suddenly forced to change direction as a result of the faucet being shut off.
An airlock will not clear itself. It acts like a restriction in the pipes and the only way to clear it is by blasting water at high pressure through it. Water pipes are hardly ever straight and that is why an airlock will not clear on its own, as it occupies the highest point of the pipes.
How to Get Rid of Air in Hot Water Pipes
Most of the time airlocks affect the hot water pipes than the cold water pipes, especially after draining the water heater. Any time you open a hot water faucet and there is no water coming out or the water is sputtering, you most likely have air trapped in your hot water pipes.
There are 2 ways of removing trapped air from your hot water pipes. The good thing is that both are really easy and quick.
Use this method if you have a double-handle kitchen or bathroom faucet. Here is how to do it:
- Block the faucet spout with your palm. Press your palm strongly against the palm to make sure that no water will flow out once the faucets are turned on.
- Turn on the hot water faucet all the way. If you have an airlock in the hot water line, you will feel no water on your palm.
- Turn on the cold water to the faucet all the way.
- Wait for 15-30 seconds.
- Turn off the cold water to the faucet.
- Remove your palm from the handle.
Once you shut off the cold water to the faucet and remove your palm from the spout, you will notice that water will flow out smoothly from your faucet, although the initial stream will be lukewarm.
If you do not have a 2-handle kitchen/bathroom faucet, there is still another way of getting rid of air from your hot water pipes. You will however need a hose and probably duct tape.
Here is how to proceed:
- Connect the hot water faucet to another working cold water faucet using the hose.
- If the connections have a potential to leak secure them with a duct tape.
- Turn on the hot water faucet followed by the cold water faucet.
- Let water run between the 2 faucets for about 10 seconds and then turn it off. The idea here is to blast the cold water through the airlock in the hot water pipe.
- Turn on a different hot water faucet and check if the problem has been fixed.
- You might need to do this about 5 times to completely fix the problem.
How to Get Rid of Air in Water Pipes
If trapped air in your water pipes is affecting all of your faucets and not just the hot water, the process to bleed off the air will be longer but totally doable. Here is how to do it:
- Turn off the water to your house. The water shut off valve to your house is located where the municipal water enters your property, closer to the water meter. It could also be on outside wall, or in the basement near the water heater. Turn the gate valve clockwise, or in the case of a ball valve put the lever at a 90 degrees angle to the pipe.
- Turn on all you cold and hot water faucets, starting with the one closest to the shut off valve to the farthest one. Do not forget outside spigots. Flush all toilets and drain the washing machine, dishwasher and fridge water line. The idea is to get rid of all the water in the pipes.
- When all the water has drained out, turn on the main house water shut off valve. Let water flow out through all the already opened faucets for 10-15 minutes to flush out all the trapped air. As a sign that air has been completely flushed from the pipes, water will flow from the faucets with a smooth stream and not sputtering.
- Flush all toilets to remove the air in the supply lines as well. Run a rinse cycle on the dishwasher and washing machine. Draw water from the fridge dispenser as well.
- Turn off all the faucets in the order of how your turned then off. This will make sure that you do not forget any of them.
And basically that is how to get rid off trapped air in your water pipes. Most of the tome this process will work and you do not need to call in a plumber. If unfortunately the problem is not solved and especially for folks using water from a well, call in a professional plumber to fix the problem.