Hot Water Tank Catastrophic Failure
Ruptured Tank Wall
Heavy Tank Sediment
Pressure & Temperature Valve Testing
A 75-gallon L.P. gas-fired hot water tank catastrophically ruptured causing significant water damage. Initial non-destructive inspection revealed a foot-long breach of a welded seam and significant bulging of the tank wall at the seam. We participated in destructive testing and the inspection focused on the seam weld, relief valve, and sediment build-up. Testing of the temperature control unit showed normal function. The relief valve was sent to an independent test facility for pressure & temperature response testing.
The relief valve tested normal but is still suspect because of significant sediment accumulation in its inlet and outlet. While not conclusive, it appears the failure was a result of significant over pressuring within the tank due to the sediment build-up in the tank’s bottom and the inlet and outlet relief valve, which allowed the water to overheat, flash to steam, and rapidly expand.