Questionable lightning strike/surge

[Norm Cal]

The sensor tubing from a pressure switch on a water booster pump separated from the pump housing and caused a flood in my office on floor below.
A commercial liability insurance claim is being denied. The insurance co. is claiming that 'acts of god' are excluded and provided a report showing 500 ground strikes within a 5 mi. radius, the closest being 0.1 mi from the property.
A forensic engineering company attributes this to a 'fused' contact in the switch. One line terminal is damaged due to arcing, with carbonization of about an inch of that wire. The pump was disposed of and we only have photos to examine. The contact itself does not appear fused or fried. The plastic portion of the switch close to the terminal screw is slightly heat damaged but does not appear charred at all. The switch cover above that terminal is slightly out of shape and looks like it was gently heated over time as opposed to a zap(to my intelligent eye since I'm not a professional).
The pump was located in the ceiling in the office above mine and in all likelihood was not maintained. From my reading, I learned that switches stick and are subject to surges and arcing/pitting for many reasons unrelated to lightning.
This incident occured over a weekend when the pump was not in use. Would a surge cause the contacts to make contact if they were in a 'resting state' (in off position)?
Even if this occured and the pump ran continuously, should this cause the tubing to separate from the barb fitting it was attached to? The steel spring clamp holding it in place was not found.
I would appreciate some insight into this situation which displaced me from my office of many years with great expense.
Thanks,
Norm

[Brian A. MacNeish]

Originally Posted by Norm Cal

The sensor tubing from a pressure switch on a water booster pump separated from the pump housing and caused a flood* in my office on floor below.
A commercial liability insurance claim is being denied. The insurance co. is claiming that 'acts of god' are excluded and provided a report showing 500 ground strikes within a 5 mi. radius, the closest being 0.1 mi from the property.
A forensic engineering company attributes this to a 'fused' contact in the switch. One line terminal is damaged due to arcing, with carbonization of about an inch of that wire. The pump was disposed of and we only have photos to examine. The contact itself does not appear fused or fried. The plastic portion of the switch close to the terminal screw is slightly heat damaged but does not appear charred at all. The switch cover above that terminal is slightly out of shape and looks like it was gently heated over time as opposed to a zap(to my intelligent eye since I'm not a professional).
The pump was located in the ceiling in the office above mine and in all likelihood was not maintained. From my reading, I learned that switches stick and are subject to surges and arcing/pitting for many reasons unrelated to lightning.
This incident occured over a weekend when the pump was not in use. Would a surge cause the contacts to make contact if they were in a 'resting state' (in off position)? NO!!
Even if this occured and the pump ran continuously, should this cause the tubing to separate from the barb fitting it was attached to? Possibly.
The steel spring clamp holding it in place was not found. Most likely didn't have one as was the case with my pump. A picture of the tubing should show whether it had a hose clamp installed or not.
I would appreciate some insight into this situation which displaced me from my office of many years with great expense.
Thanks,
Norm

* Had that happen about 14-15 years ago with the jet pump serving my current house. Luckily, a friend, who also had a jet pump, was babysitting both his and my kids that evening and realized that the pump was not shutting off. He went to the basement and shut the pump down and cleaned up the 10-12 gallons on the workshop floor.

The pressure carrying tubing had been simply slipped on over the barbed spigot and was not clamped in place. I put a very small hose clamp on and have not had a problem since.