Problem: Thermostat calls for heat, pilot igniter sparks repeatedly, I can hear gas flowing, but the pilot never lights. Eventually the pilot fails to prove, and the furnace shuts down. Is it possible that the spark isn't hot enough to light the gas?
If I light the pilot manually, the pilot proves, and the furnace cycles normally.
Once it was lit manually, it functioned properly for a few cycles. After being shut down for a day or two, the pilot fails to light again.
The flame sensor shouldn't come into play until after the pilot lights. The gas is flowing, and the spark is sparking. The flame sensor isn't involved yet.
It's a Carrier furnace. Not sure of the model, but I think it's 58GP or GS.
**Normal ignition sequence:** Heat Call Pilot valve opens Igniter spark Pilot lit Pilot proves Main valve opens Main burner lights Operating temperature reached Blower turns on.
If the pilot was lighting but the main burner was not, then I might look at the flame sensor. Since the furnace works when the pilot is manually lit, I'm going to say the flame sensor is good.
@TheEvilGreebo That's a defeatist attitude. I would go with the far more optimistic "Moderating - if you aren't pissing someone off, you can always randomly ban people"
