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Maddog0808 · Oct 22, 2009, 06:39 PM

My Carrier hasn't been used for a couple of seasons, I have tried just about everything I could find on this issue online. When I set the thermostat to the desired temperature the blower motor comes on but the surface igniter doesn't glow, I did the component test by jumping the 24V/COM and TEST connections and the hot surface igniter glows in this sequence, and it sounded like the other components did work as they were supposed to. The last LED code I could figure out seemed to be 12. Any help would be greatly appreciated. Let me know if any more information is needed. Thanks in advance.

T-Top · Oct 22, 2009, 07:34 PM

Code 12 is blower on after power up. Saying: your thermostat is calling for heat or cooling after you turn the power to the furnace off and then back on. Code 21 gas heating lock out: Manual reset time. Mis-wired gas valve or defective control relay. Turn the thermostat to off and kill power to the furnace and then turn back on. Turn thermostat to heat and make it call for heat. What did the system do?