Keeprite NG furnace code "fail to ignite"

One other thing.

The Sequence of Operation depends on whether you're using a single, or two-stage thermostat. If you're using a two-stage stat, pull the W2 wire at the terminal strip, otherwise the furnace is going to "see" a High Heat call, which somewhat negates what I've said above.

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24VAC signals applied to W1 terminal of FCB.
• Same response as single stage thermostat operation described above except the burners, inducer, and blower will not go to high
heat rate, and High Heat Fan speed unless a W2 signal is applied.
24VAC signal applied to W1 and W2 terminals of FCB.
• Same light−off routine as described for the signal stage thermostat operation except burners light at High Heat rate, the inducer
remains on high speed after ignition, and the FCB will delay High Heat blower operation for the 30−second High Heat Fan
On Delay.
NOTE 6) The FCB responds without delay to the presence or loss of W2 (with W1 constant). W1 & W2 result in high inducer, High Heat
rate, and High Heat Fan speed. W1 only results in low speed inducer, Low Heat rate, and Low Heat Fan speed.