We run several IVM600 Intelligent Valve monitors on a test system set up outside the back of our shop. It’s interesting to see how some common problems are picked up, and how the errors that are reported should actually be interpreted. In this example, we’ll see how two consecutive errors (and assumptions about the weather) show the valve almost freezing up.
Notes about the operating conditions:
- It’s January in Canada
- This valve monitor has a seat time set to 5 seconds.
- We’re pumping a 50% windshield washer antifreeze solution.
- The system is not insulated or heated.
This morning we checked an IVM6000 for errors, and the IVM reported:
5:36:12 Outlet Stuck #6 5:36:08 Inlet no Outlet
So what does this mean, How do you interpret these two errors in succession?
Answer:
- At 5:36:02 the pump panel started pumping.
- The Inlet no Outlet occurred when the seat time was violated.
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This means the valve’s internal disk only made it part of the way down and didn’t seat on the outlet.
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The pump then ran for another 4 seconds before the IVM reported Outlet Stuck.
- It (must have) reported Outlet Stuck because the previous dosing didn’t cause the cam to rotate the plunger.
Conclusion: This is a reasonable and plausible error since the operating conditions are very cold, it was 5:30 in the AM (likely the coldest point of the night) and internal icing could occur preventing the complete movement of the valve.
Corrective Action: If your system experiences freezing only very occasionally you may choose to ignore this type of error, and adjust the IVM sensitivity to medium or low. However, This is a sign that this part of the system is capable of freezing, and you may need to address that in some manner such as increasing the insulation around the valve.
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