I would appreciate any help - I have had this problem for over a year. I even had a plumber come over and the water company but no luck. I intermittantly hear water going through my water meter in the basement - the dial on the water meter spins ever so slowly. I have isolated everything in the house: sprinkler system, washer machine and dishwasher, toilets, and oil fired hot water heater and hydronic oil boiler with baseboard and 1 radiant zone. At one time, when I had a ST12 domestic hot water extrol tank on my hot water heater tied into the hot side - if I closed the lever valve to the cold side of the water heater- it would stop<the sound of running water at the meter>. I was told to take the ST12 off the hot side and it would prolong the life of the ST12. Now that I have done that, shutting the supply valve to the hot water heater does not stop the dial from spinning. I am at my wits end - few things I haven't done - food coloring in toilet tanks to see if it leaks there and someone said it could be the sprinkler isolation swing valve might have gone bad. My water consumption is not ridiculous. I noticed this problem right after we had our kitchen redone. I was also noticing that there was warm water water in the toilets. That is not as obvious anymore. I checked for reversed pipes but did't find anything. Anyone have any suggestions? Thank you