Short answer:
If your faucet is spitting air after turning the water back on, air is trapped in your plumbing lines. This is normal after a shutoff and usually clears once the air is fully pushed out of the system.
Why this happens
When water is shut off, air enters the pipes and replaces the water that drains out. Once the supply is restored, that trapped air has to escape somewhere — and it usually comes out through faucets first.
This can cause:
- Bursts of air and water
- Sputtering or spitting
- Uneven water flow
- Temporary pressure changes
This often happens after following steps like how to turn water back on after shutting it off safely, especially if faucets weren’t opened in order.
Step-by-step: what to do
1. Open the lowest faucet first
Start with a sink, tub, or hose bib on the lowest level of your home.
- Turn it on slowly
- Let it run until sputtering stops
- This allows air to escape without forcing it upward
2. Move up one faucet at a time
Once the lowest faucet runs smoothly:
- Open the next highest faucet
- Let it run until airflow is steady
- Continue floor by floor
This prevents air from being trapped in upper lines.
3. Remove and clean faucet aerators
If sputtering continues:
- Unscrew the aerator from the faucet tip
- Rinse out any debris
- Reinstall once water flows smoothly
This is especially helpful if you’re also experiencing low water pressure after turning the water back on.
4. Flush toilets last
After faucets are running normally:
- Flush toilets one at a time
- Let tanks refill fully
- Check for unusual noises or weak refill flow
What not to do
- Don’t open all faucets at once
- Don’t crank the main valve fully open immediately
- Don’t ignore continued sputtering for hours
- Don’t assume it’s “just air” if leaks appear
If air is forced too aggressively, it can contribute to issues like pipes banging after turning water back on.
When to call a professional
Call a plumber if:
- Air sputtering continues for several hours
- Water pressure never stabilizes
- You hear persistent knocking or vibration
- Faucets spit air days later
These can indicate pressure imbalance, damaged pipes, or a failing valve.
Safety notes
- Turn water back on slowly, especially in older homes
- Watch around sinks and exposed pipes for leaks
- Be cautious near electrical outlets if water sprayed
If you’re unsure your system was restored properly, review what to do immediately after shutting off water to your house before continuing.
Frequently asked questions
Is air in the pipes dangerous?
Usually no. It’s common after a shutoff and clears with proper bleeding.
How long should sputtering last?
Typically a few minutes. Large homes may take longer.
Why does one faucet still spit air?
Debris in the aerator or trapped air in a branch line is usually the cause.