Rheem Furnace Code D4
Warning
No valid model data on the model data card. The card plugged into position P6 is blank, missing or corrupted, but a good copy of the model data still lives in the control's memory, so the furnace should keep running normally.
Manual wording: “NO VALID MODEL DATA ON MODEL DATA CARD ... The model data card inserted into the slot at position P6 of the furnace control is corrupt and can not be used OR there is no model data card installed at all.”
Documented for: (-)97V, (-)96V communicating furnaces
Likely causes, most common first
- No information on the model data card (blank card)
- The card is not present
- The model data card has corrupted and cannot be properly read
What you can safely check yourself
- Nothing homeowner-serviceable. The furnace should still heat and cool normally with this code showing in standby.
When to call a technician
A technician should fit the correct replacement memory card. Never use a card from a different furnace or from a condenser/air handler.
A Rheem furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- Installation Instructions for Upflow Condensing Modulating, Communicating Gas Furnaces - (-)97V Series (92-24161-126-04) (Rheem Manufacturing Company, R97V series modulating condensing gas furnace (and R98V); TABLE 18 normal operation codes, TABLE 19 fault codes, pages 94-104) · checked 2026-08-25
- Installation Instructions for 4 Position Condensing Two-Stage, Communicating Gas Furnaces - (-)96V Series (92-24161-124-08) (Rheem Manufacturing Company, R96V series and (-)(-)96MDV two-stage condensing gas furnaces; TABLE 19 normal operation codes, TABLE 20 fault codes, pages 111-120) · checked 2026-08-25