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Could be a bad control or at least one that's out of calibration (nothing you can do to re-calibrate). Keep in mind the circs won't run unless the boiler temp is above the lo limit set point. The lo limit is what maintains boiler water temp for DHW. The hi limit is the space heating function.
Yes, if the control is functioning as designed. The circs should run as long as there is a call for heat (unless the boiler temp is below lo set point). The burner runs when there is a call for heat and the boiler temp is below the high limit. During a call for heat once off on limit the burner won't fire again until temp drops below hi less diff. Lo should always be set below hi less diff.
What's the boiler temp? If it's below 150 the circs won't run and the burner should be firing.
The only time the circs will run and the burner not fire is if there is a call for heat and the burner runs up to hi limit then shuts off on limit. While the temp is falling back to hi - diff only the circ will run.