Rheem R802VA07542117MSA Error Code A221_F: Configuration Data Restore Failure

What Does Code A221_F Mean?

Fault code A221_F on the Rheem R802VA means the Integrated Furnace Control (IFC) tried to reload its configuration data from onboard non-volatile memory when it powered up, and that reload failed. Configuration data is separate from the model data covered by A222_F — it holds this installation's operating settings, the parameters a technician sets up rather than the fixed specifications of the furnace model itself. Because the Bluetooth Communicating IFC design keeps this data in memory rather than hard-coding it at the factory, the board depends on being able to read it back correctly every time it starts.

A restore failure here means that memory read came back corrupted, blank, or unreadable. That can happen from a power surge that damaged the memory cells, gradual wear of the non-volatile memory over time, or — on a freshly installed board — configuration that was never actually written in the first place, since a brand-new IFC has nothing valid to restore until a technician programs it.

A221_F and A222_F are the configuration-data and model-data versions of the same restore-failure problem, and they can appear together on a board that lost both records at once, such as after a surge or a botched initial programming session. Seeing only one of the two narrows down which specific memory record is affected, which helps a technician decide whether a partial reprogram is enough or the board's memory itself is unreliable.

A power cycle alone does not fix A221_F, because cycling power is exactly what triggers the failed restore attempt in the first place — the missing data has to be rewritten through the Bluetooth contractor app before the furnace will run correctly again.

What You'll Notice

• The furnace fails to start a normal heating cycle after being powered on
• The alphanumeric display shows A221_F
• The furnace behaves as if never configured, even though it previously ran normally
• The fault appears after a power outage, surge, or a new board installation
• Repeated power cycling does not clear the code

Common Causes

How This Is Diagnosed

A technician connects to the IFC with the Rheem contractor app over Bluetooth and checks whether any configuration data is present, and if so whether it reads as valid or corrupted. If the fault started after a known power event, the technician also looks for other signs of surge damage on the board before assuming the memory failure is isolated to this one record.

The technician then attempts to write a fresh configuration through the app. If the write is accepted and the board retains it through a subsequent power cycle, the memory is functioning and only needed reprogramming. If the board cannot hold newly written data, that indicates a failing memory chip on the IFC and points toward board replacement rather than repeated reprogramming.

When to Call a Professional

This code involves components that are not homeowner-serviceable, so have a licensed HVAC technician diagnose and repair it. Keep in mind:

• The display shows A221_F and the furnace will not run a normal cycle
• The fault appeared after a power outage or surge
• Configuration was reprogrammed previously and the same fault has come back
• A221_F and A222_F both appear at the same time, suggesting broader memory trouble on the board

✓ Verified against manufacturer service manual — March 2026