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AMERICAN STANDARD DIAGNOSTIC REFERENCE AMERICAN STANDARD SILVER S8X1 FURNACE CONTROL DISPLAY (2024 IOM) DOC AMERICAN-STANDARD-CP2

American Standard S8X1 furnace code CP2: Second-stage compressor

CP2 YOUR LIGHT: THREE-CHARACTER DISPLAY: CP2, ALTERNATING WITH BLOWER TAP — MATCH IT ABOVE

Info — not a fault

What does CP2 mean on an American Standard Silver S8X1 gas furnace display? CP2 means the thermostat is calling for second-stage cooling or heat-pump operation. On the S8X1 this is a normal demand display, not a furnace fault.

Safe checks before calling

If you expected gas heat, check whether the thermostat is set for cooling or heat-pump operation.

Questions about this code

What does CP2 mean on an American Standard Silver S8X1 gas furnace display?

CP2 means the thermostat is calling for second-stage cooling or heat-pump operation. On the S8X1 this is a normal demand display, not a furnace fault.

Does American Standard S8X1 furnace code CP2 mean I need a repair?

CP2 needs no repair. If the home is uncomfortable while it shows, a technician should check the outdoor equipment and thermostat staging rather than the furnace burner.

How much does it cost to fix American Standard S8X1 furnace code CP2?

CP2 is a normal display and implies no repair bill. Cost arises only if a separate cooling or heat-pump problem is diagnosed.

Applies to

S8X1A040M3PSCA · S8X1B040M2PSCA · S8X1B060M4PSCB · S8X1B080M4PSCB · S8X1C080M5PSCA · S8X1C100M5PSCB · S8X1D120M5PSCA

Different American Standard generations use different code maps. If your series isn't listed, don't assume this meaning — check your blower-door label.

Verified against Installation, Operation, and Maintenance — Upflow/Downflow/Horizontal Gas-Fired,1–Stage and2–Stage Induced Draft Furnaces with High Efficiency Motor, p.55

Last verified 2026-10-07 · page updated 2026-10-07 · how we verify

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These codes use the same american standard silver s8x1 furnace control display (2024 iom) system.

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