Furnace won't heat

I believe what you're saying is that it goes normally until it should light. Is the click sound coming from the gas valve solenoid? Have a voltmeter to see if it has 24V for it to open? If it's clicking, I'd check for gas before the valve, any chance of an obstruction? The inside of the door panels usually have the key to the number of blinks and the problem. Sounds like the igniter is hot, but the gas doesn't arrive to get lit.

He might also check for an open coil on the gas valve. This in not uncommon. Do so with one wire on the coil disconnected.

He might also check the igniter.

I've got a small central-air furnace and the igniter goes away about every 5 yrs. It jes "burns" away, so there is zero ignition to the propane gas. I've replaced 2 in the last 10 yrs. I now keep a new one next to the main furnace, awaiting the next failure.

(Damn inconvenient to lose one's furnace at 3 o'clock in the morning and it's minus degrees, outside!) ;)

nb