You ll often see this when someone on your block turns on their sprinkler system or a fire hydrant is opened.
Water meter leak indicator going back and forth.
Backflow can occur due to either back pressure or back siphonage which are essentially too high or too low of pressure in the system.
I recently noticed that the red triangle on the face of my water meter was moving back and forth by about 3 4 of a revolution.
The flow needle was turning slowly forward then backwards stopping then forward then backwards and stopping it just kept doing that.
So if there is a pressure build up from the street it would force water into the house and then the wheel would go backwards as the pressure equalizes.
I think it is water pressure fluctuations in the system.
That said i ve never seen it happen quite that much.
I have seen the flow indicator on older mechanical meters show a back and forth surging so i would say it s normal.
Backflow is when water flows incorrectly in the wrong direction.
When the pressure rises more water is forced into the home.
That means there is a leak between your water meter and your side of the shut off valve.
Each time it moved forward backwards forward it ended up a little past where it was.
So we are now back to the meter face now check if the meter s leak detector hand is moving.
There are several external signs that you can look for around your water meter to determine if you have a leak.
Thursday june 21 2018 most water meters have a leak detection spinner in the shape of a triangle star or arrow that can show low level water flow.
If the leak indicator or dial hand is still rotating then water is flowing somewhere between the meter and the shut off valve.
All is well with your system.
This would definitely make the meter spin backwards and warrants a call to your local plumber.
When the pressure increases some water goes into your system to equalize the pressure which makes the dial tick forward.
Then when the pressure decreases water flows out.
On my inspections i always look at the water meter to see if the flow needle is stopped when all the water is off in the home.
If it is moving forward clockwise there is water flow.
I looked at the meter next to it just for comparison it was stopped and steady.
I m not saying it is backwards just that it will act like that if there are pressure changes.
If it twists slowly back and forth that can be caused by fluctuations in water pressure and is not a leak indicator.
Today i saw something new.
When the pressure drops then the excess pressure in your system flows backwards again to equalize the pressures which makes the dial tick backwards.
I didn t have any fixtures etc turned on while this was happening.
If the meter is installed backwards the meter will do that.
It could be on the city side and if that is the case then you won t be charged.
If you walk out to your water meter and notice the area around it is wet and soggy or you see standing water and puddles then you have a leak with the water from the main line coming into your home.
