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You probably removed the black wire to the Honeywell block in the 8124. Put it back and remove the blue wire; the blue one controls the burner low limit. Also turn the low limit knob all the way down – the one on the right – so the circulator will come on sooner. This will prevent sending very hot water out to cold piping and radiation expanding them suddenly.
One way is to change the control from an 8124G or H control to an 8148A which has no low limit and circulator temperature controls in it. But allowing the boiler to use the low limit feature of the 8124 reduces the temperature swing of the boiler and may help prevent leaks due to the ‘working’ of the seals from temperature changes in mild weather. So you could leave all wires connected and just turn the low limit side all the way down to 120F or so.