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Help!
20 year old Ruud 90 Plus condensing gas furnace with JCI G961DAJ-2401 controller keeps blowing its 24V AC 2 Amp fuse. I tightened the wires, nothing looks wrong.

I measured the current for each step:

mA       Step
84       Start. No call for heat.
260      Draft induction motor on.
770      Gas valve open, flame on
880      Blower motor on
300      Gas valve closed
84       Blower motor off

Photos:
https://photos.app.goo.gl/63jWLBLmiqGFB56U8

I am measuring the current in series with the inline fuse from the 24V AC transformer on its way to the Johnson Controls controller board.

I’m stuck. Any ideas?