Verified answer

I ran into the same issue you're having about 5 years ago for my furnace. Turns out there was a faulty relay on the circuit board, which was not powering up the induction blower to start the heating sequence, and like your issue, sometimes flicking the power switch for the furnace, a time or two, would get that relay to work.

I'm a handyman, not an HVAC tech, but could hear the relay struggling sometimes, so I just replaced the circuit board and all is well.

My wife's aunt lives down the street and has the same furnace, also had the same issue we had the following year. She called me up to have a look, and hers was the same relay as mine, that was failing.

There is instructions on one of the service panels doors on the furnace, that will tell you how to sequence the induction blower, the igniter, and the main blower (but not the burners), to make sure they work properly.

Hers, like mine, failed the same way, and said I could replace the circuit board for under $300. To get a second opinion, she called a heating/cooling company, and they talked her into replacing the 13 year old furnace to the tune of $4k.

While there are many other things that could cause your furnace issues too, get two opinions from trusted sources.

Good luck.

And you have electric, gas, propane, steam, geothermal ______________? Please never heat with coal or wood as these fuels are filthy and will pollute your neighborhood.

Could be a bad thermostat or a bad control board. Call a heating technician.

May require a new thermostat.

You didn't even hint at the type of heating you have. Based on what little you say we can only narrow our GUESS to everything that can go wrong.

I recommend having someone actually inspect the unit.

My current focus is creation and evolution