Ruud U802VA050317MSA Error Code *A228_F: Internal Fault: Gas Valve 2 Relay Stuck Open (Two-Stage Only)
What Does Code *A228_F Mean?
A228_F applies to two-stage models only. It means the Bluetooth Communicating IFC has detected that the relay controlling gas valve 2 — the high-stage (high-fire) valve — is stuck open and will not close. Because the relay can't close, the control cannot energize the high-stage valve, so the furnace loses its high-fire stage.
This is not an uncontrolled-gas hazard: the high-stage valve simply can never be energized, so there is no risk of unwanted gas flow. In many cases the furnace can still operate on low fire, providing partial heat, but it cannot step up to high fire on demand — so on the coldest days it may struggle to keep up. A228_F is the opposite failure mode of A227_F (Gas Valve 2 Relay Welded Shut), and the high-stage counterpart of A226_F (Gas Valve 1 Relay Stuck Open) on the primary valve. Single-stage furnaces have no second gas-valve relay and will not show A228_F.
The relay is integral to the IFC, so the board is replaced rather than repaired. A technician installs a new IFC, programs it over Bluetooth with the model and blower data from the furnace's QR code, and confirms both low- and high-stage gas-valve relays operate before returning the furnace to full service.
What You'll Notice
- The furnace heats only on low fire and never steps up to high fire.
- On very cold days the home is slow to reach temperature.
- The contractor app shows A228_F on a two-stage unit.
- You do not smell gas — the high-stage valve is simply never energized.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Failed relay contacts on control board | Most common | ✗ Call a pro → |
How This Is Diagnosed
A technician confirms A228_F in the Ruud contractor app and identifies it as the stuck-open (no-energize) failure of the high-stage gas-valve relay on a two-stage furnace. They verify the control calls for high fire but no voltage reaches the high-stage valve because the relay won't close, while low-stage operation may remain normal; since the relay is part of the board, the IFC is replaced and programmed over Bluetooth for the model.
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 furnace runs only on low fire and will not step up, with A228_F shown
- The home cannot keep up on the coldest days
- The two-stage fault does not clear after power is cycled
- The control board needs replacement and Bluetooth programming to restore high fire
Frequently Asked Questions
Will my furnace still heat with A228_F?
Often yes, on low fire only. It loses high-stage (high-fire) operation, so on very cold days it may not keep up until the board is replaced.
Is A228_F a safety hazard?
No. The high-stage relay is stuck open, so the valve can never be energized — there is no uncontrolled gas flow. The issue is reduced heating capacity.
Could a single-stage furnace show A228_F?
No. It is a high-stage (gas valve 2) code that only exists on two-stage models.
✓ Verified against manufacturer service manual — March 2026