Rheem and Ruud furnace code 68: no blower communications

Furnace control display or LED

68

“No Blower Communications”

(-)96V & (-)(-)96MDV, (-)97V, (-)98V, (-)802V UPFLOW/HORIZONTAL & (-)(-)80MDV, (-)802V DOWNFLOW & (-)(-)80DDV · 92-24161-124-12 p. 120; 92-24161-126-04 p. 104; 92-24161-159-03 p. 101; 92-24161-148-07 p. 73; 92-24161-149-06 p. 68
Technician

What it means

68 says the furnace control (I.F.C.) cannot communicate with the blower motor. It is a code of the communicating furnaces with an ECM blower: the 96V, 97V, 98V and 802V 92-24161-124-12, p. 120; 92-24161-148-07, p. 73. The card rates it critical, and the furnace does not run in any mode 92-24161-124-12, p. 120. The 96V diagnostics chart gives 68 fault level 2, a critical fault, at priority 3, behind only 30, 93 and d1 (96V-chart).

If 68 appears during heating, the gas valve closes at once and the flame goes out, the blower stops, and the furnace shuts down without the blower, with an inducer post-purge. After that nothing runs, thermostat calls included, until the fault clears 92-24161-124-12, p. 120.

The card lists four causes 92-24161-124-12, p. 120; 92-24161-148-07, p. 73:

• The wires to the blower motor have been disconnected, or there is a poor connection.
• There is no line voltage at the motor.
• The furnace model data is faulty or corrupted.
• The motor has failed catastrophically.

The model data comes from a factory-installed model data card, wire-tied to the furnace, from which the control receives model-specific data. The manual says the card should never be removed from the furnace except during replacement of the control 92-24161-124-12, p. 92.

Check these first

Rheem’s owner’s manuals have no code list and no reset (92-20802-128-03; 92-20802-130-02). For a furnace that will not operate, the last of their operating instructions gives two steps 92-20802-128-03, p. 4; 92-20802-130-02, p. 4:

1. Turn off the gas to the furnace by “To Turn Off Gas To The Appliance”: shut off the manual gas valve in the gas supply piping outside the furnace casing, set the thermostat to its lowest setting, turn off all electric power to the appliance if service is to be performed, remove the burner access door, turn the gas control knob or switch to OFF and replace the door 92-20802-128-03, p. 4. In that list the power step is conditional, but the manual’s warning is to turn off electrical power to the furnace before removing the front access door 92-20802-128-03, p. 7, and its operating instructions turn off all electric power before the burner access door is removed 92-20802-128-03, p. 4. Full steps: shutting the furnace down.
2. Call your service technician or gas supplier 92-20802-128-03, p. 4.

The causes of 68 are inside the furnace: motor wiring, line voltage at the motor, the model data and the motor itself. The owner’s manuals give no electrical check; their warning is to disconnect all electrical power to the furnace before servicing 92-20802-128-03, p. 6; 92-20802-130-02, p. 6, and they leave routine maintenance to a qualified installer, service agency or the gas supplier 92-20802-128-03, p. 7.

When to call a licensed technician

The card’s solutions are service work, one of them on line-voltage wiring 92-24161-124-12, p. 120; 92-24161-148-07, p. 73:

• Checking the wiring, connectors and terminals to the blower motor, and repairing or replacing them.
• Checking the line-voltage wiring, connectors and terminals to the power factor correction choke and the ECM motor, and repairing or replacing them.
• Replacing the furnace memory card with the correct replacement part “from ProStock”, as the card puts it.
• Replacing the motor.

The manual warns against putting a control or memory card from another furnace or another component, such as a condenser or air handler, into the furnace 92-24161-124-12, p. 92. The owner’s manuals say installation and service must be performed by a qualified installer, service agency or the gas supplier 92-20802-128-03, p. 1.

Notes for different models

Series	Where	Wording	Source
96V, 802V	fault card	“NO BLOWER COMMUNICATIONS”	92-24161-124-12, p. 120; 92-24161-148-07, p. 73; 92-24161-149-06, p. 68
97V	fault card; the solution field could not be extracted	“NO BLOWER COMMUNICATIONS”	92-24161-126-04, p. 104
98V	fault card, title only	“NO BLOWER COMMUNICATIONS”	92-24161-159-03, p. 101
96V, 97V, 98V	diagnostics charts	“No Blower Communications”, fault level 2, priority 3	96V-chart; 97V-chart
Fault code label 92-103343-01-00 (listed on the RGGE and RGJF support pages)	label, no models printed	“No Communications with Blower Motor”	92-103343-01-00, p. 1
92P, 92T, 95P, 95T, 96P, 96T, 801S, 801P, 801T, 802P	code list	no 68	92-24161-111-17, p. 87; 92-24161-122-12, p. 88; 92-24161-144-09, p. 39; 92-24161-146-05, p. 40

Related model data codes on the communicating furnaces: d1, “NO MODEL DATA”, stops the furnace, while d4 and d6 are non-critical card problems; all three are described on the same cards 92-24161-124-12, p. 112. The 97V card gives the same status and causes as the 96V card 92-24161-126-04, p. 104.

For Ruud, the documents show only the replacement-parts line “www.myrheem.com/myruud.com” in the 802P manuals 92-24161-146-05, p. 50; 92-24161-147-04, p. 46 and the model name R801T on both a Ruud and a Rheem specification sheet (G22-556 Rev 8; G11-662 Rev 7); none ties a Ruud furnace to a series on this page.

Related Rheem and Ruud codes

• 61 “BLOWER FAULT – BLOWER UNABLE TO RUN”
• 66 “Blower Cutback”
• d1 “No Model Data”

See also

• Heat pump vs gas calculator
• HVAC and furnace tax credits in 2025 and 2026: 25C, 25D, 30C

Other gas furnaces: Carrier, Goodman, Lennox

All Rheem and Ruud codes

Rheem and Ruud is a trademark of its owner. How House Works is not affiliated with or endorsed by Rheem and Ruud.