Service to replace propane gas regulator (customer supplied):on a Rheem brand 40 gallon propane water heater. Installed new regulator but u it would not ignite. I observed that the water heater had a broken glass window for the burner compartment. I advised owner and he explained that a tech from another company attempted to light the unit with a torch the day before and he heard a gas explosion inside the unit. Payment received. Customer was provided an estimate to replace the damaged water heater with a new unit. Customer will contact the previous company to advise what he observed the previous tech do with his water heater and will contact us to replace.