Gas Leak Problem

[HootonJack]

Propane company installed large tank for on-site service today. Spent 3 hours trying to find a leak that they were detecting. It was intermittent and tough for them to pinpoint but finally traced it to the water heater. Again - the valve was showing it was leaking - then not. They capped it off for now. Anyone have a clue why this would happen??

Thanks Jack