Runaway Blast Pot Troubleshooting: Solve Deadman Shutdown Issues

If your deadman won’t turn off, it’s almost always due to a valve failure. Here’s how to troubleshoot the most common culprits:

Start by checking the control valve. Remove the bottom signal line from the control valve and depress the deadman.

If air flows through the signal when the deadman is released: The control valve is likely the issue.
- Solution: If you have a service kit, rebuild the valve. If you’re in the field without the kit, try removing the plunger, cleaning the control valve, and lubricating the plunger with grease or chapstick before reassembling. This may temporarily solve the problem.
If air doesn’t flow through the signal when the deadman is released: The issue may lie with the auto air valve. Move on to the next step.

Close the TeraValve and shut off the Ball Valve to isolate the air currently exhausting.

If air continues to exhaust without abrasive: The auto air valve is stuck in the open position, likely due to debris or friction between the plunger stem and the assembly.
- Solution: If you have a rebuild/service kit, rebuild the valve. If not, remove the diaphragm and puck stem, disassemble and clean the valve, apply a dry lubricant to the stem, reassemble, and test. If air ceases, the auto air valve is closing properly.
If air continues to flow: The issue may be with the TeraValve. Proceed to the next step.

Release the deadman. If abrasive continues to stream from the nozzle without any pressure, the TeraValve is not closing properly.

Solution: Rebuild the valve if you have a kit. If not, disassemble the valve, clean out dust and debris, and apply a dry lubricant to the plunger (avoid grease, as it can cause buildup). If the abrasive flow stops, the TeraValve and auto air valve are working properly.
If the abrasive flow doesn’t stop: This could indicate a larger issue. Contact us for further assistance.

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