Is the Gas Valve on Your Water Heater Leaking?
The new water heater was just installed and now it’s time to test it. Cold water in hot water out, no leaks. Now it is time to test the gas. The gas detector is showing a presence of gas. All the gas connections are tightened and then a retest is performed. Still, a trace of gas is detected. Is the gas valve bad? The short answer is no.
According to North American requirements that are outlined in UL429, ANSI Z21.21/CSA 6.5 and ANSI Z21.78/CSA 6.20, maximum external leakage is 200cc/hr. These standards and values have been deemed safe by the respected agencies listed above and have been established for decades.
Electronic gas detectors do not quantify the gas detected in the atmosphere. These detectors only identify gas in the vicinity in parts per million. With many variables such as the heater placement, fresh air turnover, and other gas appliances in the room it is nearly impossible to correlate gas detector readings to a valve’s leakage rate. Although these detectors can distinguish gas below the safe leakage rate of a valve it often leads to misplaced safety concerns. This results in the unwarranted replacement of expensive gas valves that meet all safety requirements.
| 
