Rheem R802VA07542117MSA Error Code *T082_F: Supply Air Sensor Fault (Two-Stage Only)

What Does Code *T082_F Mean?

On your two-stage, variable-speed R802VA07542117MSA, the supply air sensor is a thermistor that measures the temperature of heated air just after it leaves the heat exchanger and enters the supply ductwork. The Bluetooth Communicating IFC (Integrated Furnace Control) reads this sensor together with the return air sensor to know the temperature rise across the furnace, which is one of the inputs it uses to run the variable-speed blower correctly. Rheem flags T082_F as a two-stage-only fault because single-stage versions of this control do not carry this supply-side sensing. The code is logged when the thermistor's resistance reads outside the valid range, typically from a failed sensor, a disconnected wire, or a corroded connector.

Because the supply air sensor is a monitoring input rather than a combustion-safety device, the furnace does not lock out. Rheem rates T082_F as low severity, so the burner still lights and warm air is still delivered. What is lost is the control's ability to accurately watch discharge temperature, so it can no longer use that reading to fine-tune airflow or to notice when supply temperatures are running high.

T082_F is the supply-air member of this board's air-temperature sensor group, which also includes T081_F (return air) and T084_F (outdoor air). It is separate from the cooling-system EXV superheat sensors, T085_F, T086_F and T088_F, and from T087_F, which watches the control board's own temperature. All of these are low-severity monitoring faults and must not be confused with the furnace's hard-lockout codes.

Because supply and return sensors are read as a pair for temperature-rise math, T082_F and T081_F sometimes appear together when a shared harness or connector is disturbed. If the code appeared only once and then cleared, a loose connector is more likely than a fully failed sensor.

What You'll Notice

• The alphanumeric display shows "T082_F", or the LED blinks the code one digit at a time with a roughly three-second pause between digits
• The furnace still lights and delivers heat, so registers feel normal
• Airflow may seem slightly less finely matched to the heat call than before
• The fault stays logged in the Bluetooth contractor app history after a power cycle
• No lockout occurs and the thermostat continues to be answered

Common Causes

How This Is Diagnosed

A technician locates the supply air thermistor in the discharge airstream and its connector at the control board, then measures the sensor's resistance and compares it against the expected value for the current air temperature. An open or out-of-range reading indicates a failed thermistor, while a good reading at the sensor but a bad one at the board points to a broken wire or a loose or corroded connector.

The harness and plug are inspected for heat damage, chafing and corrosion and the connector is reseated, since the supply-side sensor sits in a warmer location than the return sensor. If the resistance is correct and stable at the board yet the code persists, the control's sensor input is evaluated. This is informational only; this work is not homeowner-safe.

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 code remains active and you want the furnace to regain accurate supply-temperature monitoring
• You also see the return air code T081_F, suggesting a shared harness or connector problem
• The code keeps clearing and returning, hinting at an intermittent connection rather than a dead sensor
• You want the correct two-stage supply sensor part confirmed for this specific model before a repair

✓ Verified against manufacturer service manual — March 2026