Recurring Backflow / Abrasive Clogs

If you find that after a backflow or a abrasive clog, you get another immediately or even shortly after, the situation indicates that you have other problems waiting to be solved. There are two likely root causes.

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When troubleshooting recurring backflows, often the best place to start will be to perform a quick check of the systems that could cause this issue. This quick check consists of a three part test, in each part you will perform a Nozzle Purge and observe a different part of the WAZER.

For the first two tests, please remember to remove the abrasive hose from the nozzle.

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1. During the first test, run a Nozzle Purge and observe the Low Pressure Gauge on the Water Inlet Filter Canister. Make sure the needle can reach the green area on the gauge.

If the pressure gauge on your inlet filter does not reach the green zone, please make sure the water supply is on and the flush valve is closed. If the pressure gauge still cannot reach the green zone, confirm that your water input can supply 1 gal/min at 35 psi and reach out to Support.

2. During the second test, run a Nozzle Purge and observe the High Pressure gauge located on the side of the pump box. Make sure the needle can reach the green area on the gauge and does not fluctuate while water is exiting the nozzle.

If your High Pressure gauge needle does not reach the green zone or the needle fluctuates under pressure, please reach out to Support.

3. During the final test, reinsert the abrasive hose into the nozzle. Remove the other end of the abrasive hose from the abrasive catcher and cover this end with your finger. Keeping your finger over this end of the hose, run a Nozzle Purge. You should feel a strong suction through the abrasive hose.

If you cannot feel suction, please attempt to blow any blockages out of the abrasive hose by blowing compressed air through this end. If you still cannot feel suction, reach out to Support.

If either of the gauges do not reach the green zone or if you are unable to feel suction through the abrasive hose, please reach out to Support for further troubleshooting.

Checking the Nozzle Clearance

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Check: Is the Cut Bed Level?

• Root Cause: If the cutting bed is not level, your nozzle offset may be decreased at a low part of the cute piece. During the operation, the nozzle will touch one of the high parts of cut piece.

• Corrective Action: Leveling or Replacing the cutting bed will ensure that the nozzle does not touch the work piece.

Check: Is the Cut Bed too chewed up?

• Root Cause: If the cutting bed is completely used up, it may not have the rigidity to keep your material flat.

• Corrective Action: Flip or replace the Cut Bed will ensure that the work piece is well secured and the nozzle does not touch it.

Check: Were tabs enabled in WAM?

• Root Cause: If a part that is cut out floats up and gets between the nozzle and the work piece this will cause a back flow

• Corrective action: Enable tabs in WAM. The tabs only need to be large enough so the piece is just held

Check: Is the Z-adjusting knob tight before starting the cut?

• Root Cause: If the head were to drop into the work piece during the cut, it would cause a backflow.

• Corrective Action: Check that the knob is tight before every cut

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Checking the Abrasive System

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Check: Is the abrasive valve fully closing?

• Root Cause: If the valve doesn't fully close then abrasive will remain in the hose. This abrasive then gets wet and creates a clog in the abrasive hose.

• Corrective Action: Do a Quick Abrasive Valve Check

  • If it doesn’t feel smooth, Rebuild the Abrasive Valve

Check: Is the abrasive flow rate too high?

• Root Cause: Over time the abrasive orifice can increase in diameter, increasing the abrasive flow rate. Too high of a flow rate causes too much abrasive to enter the hose, leading to clogs.

• Corrective Action: Perform a Abrasive Flow Rate test and determine your flow rate. If it is outside of the ideal range, replace the abrasive orifice with the alternative sized orifice.

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Checking the Low Pressure System

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Check: Is the low pressure inlet supply below 25 psi or are there sudden drops in inlet pressure?

• Root Cause: Low supply pressure will cause the high pressure output of the pump tp dip momentarily. These dips mess with the suction of the of abrasive into the head and can lead to water and abrasive mixing in the abrasive hose. Lading to a clog

• Corrective Action: Make sure the inlet pressure is to spec and that no water hungry devices (utility sink, washer, etc) are turned on during a cut.

Check: Can your inlet water supply a minimum of 1 gallon per minute?

• Root Cause: If the inlet water supply flow is too slow it will not provide enough water to the pump to operate properly.

• Corrective Action: Make sure you are able to supply 1 gallon per minute minimum.

  • To test your inlet water supply, remove the inlet hose from the pump box and fill a 1 gallon bucket with it, if it cannot fill within 1 minute then your inlet flow is too low.

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Checking the High Pressure System

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Check is the orifice in good health? Follow the guide here to check the stream.

• Root Cause: A slightly damaged orifice will look similar to a working one once the stream has been focused by the nozzle. Despite how it looks the cutting potential is greatly reduced.

• Corrective Action: Replace the Orifice

Check:  Is there a knocking coming from the pump box.  

• Root Cause: When the orifice is broken the pressure setting device on the pump struggles to achieve pressure and make a loud noise

• Corrective Action Replace the Orifice

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