Carrier high efficiency furnace blower not turning when thermostat set to on position

If you have a voltmeter, with the thermostat in the heat position and turned several degrees above room temperature, check for 24volts across terminals W and C. If you do not have 24 v there, the problem is in the thermostat or the wires between the furnace and the thermostat.

If you do have 24 volts between W and C, the problem is in the furnace....No idea what brand of furnace you have or whether or not its a high efficiency or not, so here's some generic things to look for.
Look for a "manual reset limit switch" in the furnace vestibule or towards the top inside on the front panel. Also some manufacturers have a manual reset limit switch mounted on the blower. Check for 24v on the gas valve...if its a three terminal valve, the middle terminal is usually a dummy. The two outside terminals should be the 24v to the coil that causes it to open on a call for heat.

Oh yeah, once the pilot was lit manually, make sure the knob was rotated from "pilot" to the "on" position.

You could have open pressure switch caused by a vent blockage if its high efficiency. But if its high efficiency, there should be a set of LED's to blink a failure code. If so, count the blinks and look for the list of failures on the inside of the door of the furnace.

This answer pertains to your question which is similar to another I just provided some input for.

If you have a voltmeter, with the thermostat in the heat position and turned several degrees above room temperature, check for 24volts across terminals W and C. If you do not have 24 v there, the problem is in the thermostat or the wires between the furnace and the thermostat.

If you do have 24 volts between W and C, the problem is in the furnace....No idea what brand of furnace you have or whether or not its a high efficiency or not, so here's some generic things to look for.
Look for a "manual reset limit switch" in the furnace vestibule or towards the top inside on the front panel. Also some manufacturers have a manual reset limit switch mounted on the blower. Check for 24v on the gas valve...if its a three terminal valve, the middle terminal is usually a dummy. The two outside terminals should be the 24v to the coil that causes it to open on a call for heat.

Oh yeah, once the pilot was lit manually, make sure the knob was rotated from "pilot" to the "on" position.

You could have open pressure switch caused by a vent blockage if its high efficiency. But if its high efficiency, there should be a set of LED's to blink a failure code. If so, count the blinks and look for the list of failures on the inside of the door of the furnace.

Hi smargyle,

Welcome to fixya!

I can provide you with diagrams for the old Carrier therm and for the new Filtrete therm. But, I would need to know what the model numbers are for each therm plus how many speeds AC you have.

Please reply back with that information and we will get your AC back in working order.

Thanks,

Handie Andie

carrier infinity 96 furnace went to turn down the thermostat and their was no power to it and the furnace doesnt run

Is this a gas furnace if so is it high efficient if so is there an led light on the furnace blinking a code usually seen through a window at the furnace. is the thermostat battery operated if so is it a new battery and are the aif filters new. These would be my first steps to check hope this helps

Did the installer check the amperage at your thermostat and then adjust the heat anticipator? Or you may need to have the blower time settings changed to suite your needs. Get them back in to check.

I would have the the burners cleaned, you may be hearing a clog starting to form at the valve on the furnace.

Most furnaces have a photo cell if it gets dirty the photo cell does not see a flame so it trips the reset button on flame failure.