24 VAC or 115 VAC off fuse is open

Frequently, my furnace won’t kick on. The thermostat says it should, but nothing happens.

The LED is off which the furnace says is: 24 vac or 115 vac is off fuse is open

If I power cycle the furnace it will work fine for hours or days. The led code then indicates normal operation. Any ideas before I call an hvac guy?