Plumbing – Water meter leak indicator moves once in a while

leakplumbingwater-meter

What is driving me a bit not sure recently is that the water meter leak indicator sometimes can move a bit over a long period (say an hour or a few hours). My water meter is a Procoder meter same as below.

I guess the smallest interval for the red leak indicator is 0.0001 cf which is about 0.1 oz or 2.8ml. Not sure if my reading is correct.

The red indicator sometimes can move a few intervals (~10ml) over a period of a few hours. But sometimes it just makes no movement over a period of a few hours. I wonder whether this is acceptable?

I cannot figure out what is happening. I do have a 40 gallon water heater and a water expansion tank (2.1 gallon). I sometimes wonder whether it can be just temperature fluctuation which causes either the water or the air in the expansion tank to contract/expand. Any suggestions?

Btw, I am doing this because the house had some pipe work and garden sprinkler lines done recently, and I am checking for possible leaks.

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Best Answer

Max, with that small of a “leak” I would not worry about it but I may try an experiment where you turn your water heater off for several hours and see if it is any different this test may be more accurate if some hot water was used after the water heater was turned off so the cooling down or cycling of the water heater might be eliminated as the cause but .0001 cult is a very small amount of water. And probably not worry about as it is not a consistent leak and may be due to water heater temp cycling.