Rheem and Ruud furnace code 0: standby, not a fault

Furnace control display or LED

0

“Standby”

Printed on 13 model series · 13 documents

(-)92P & (-)(-)92MSP, (-)92T & (-)(-)92MSX, (-)95P & (-)(-)95MSP, (-)95T & (-)(-)95MSX, (-)96P & (-)(-)96MDP, (-)96T & (-)(-)96MDT, (-)801S / (-)801P UPFLOW/HORIZONTAL & (-)(-)801MSS / (-)(-)801MSP; (-)(-)80MSS / 80MSP, (-)801S / (-)801P DOWNFLOW & (-)(-)80DSS / 80DSP, (-)801T UPFLOW/HORIZONTAL & (-)(-)80MSX, (-)801T DOWNFLOW & (-)(-)80DSX, (-)802P UPFLOW/HORIZONTAL & (-)(-)80MDP, (-)802P DOWNFLOW & (-)(-)80DDP, Fault code label 92-103343-01-00 · 92-24161-118-16 p. 87; 92-24161-154-03 p. 87; 92-24161-111-17 p. 87; 92-24161-120-16 p. 87; 92-24161-122-12 p. 88; 92-24161-157-04 p. 88; 92-24161-142-15 p. 39; 92-24161-143-14 p. 34; 92-24161-144-09 p. 39; 92-24161-145-10 p. 34; 92-24161-146-05 p. 40; 92-24161-147-04 p. 35; 92-103343-01-00 p. 1

Owner can check

What it means

0 is the display at rest. Rheem’s manuals say that in standby mode with no fault codes present the display reads 0 (zero) 92-24161-144-09, p. 39. The normal operation code cards define it as no fault present and no thermostat call present: the furnace is idle 95P: 92-24161-111-17, p. 87; 96V: 92-24161-124-12, p. 111.

Any fault takes its place. In the 96P code list 0 has the lowest priority, 24, and the control shows a lower priority number over a higher one 92-24161-122-12, p. 88; 92-24161-157-00, p. 88. When the thermostat calls, 0 changes to a mode letter: H for gas heat, h for low gas heat on two-stage furnaces, C for cooling or heat-pump heat, F for continuous fan 92-24161-144-09, p. 39; 92-24161-122-12, p. 88. On the communicating furnaces 0 also shows while the blower runs its off-delay after heating or cooling 92-24161-124-12, p. 93.

So a furnace that shows 0 and is not heating has no call for heat present at the control and no fault on the display. During a lockout the control shows the lockout code, even in place of C or F when it answers a cooling or fan call 92-24161-144-09, p. 40.

Check these first

From Rheem’s owner’s manuals for condensing and 80% furnaces, in their order 92-20802-128-03, p. 4; 92-20802-130-02, p. 4:

1. Keep heat from a television, lamps or radios away from the thermostat: the manual asks you not to let it influence the thermostat’s operation 92-20802-128-03, p. 4.
2. The manuals describe the thermostat’s switches: HEAT turns heating on when the temperature drops below the desired temperature, AUTO turns heating or cooling on as needed to hold the desired temperature, and OFF turns heating and cooling off. They do not tell the owner to check them when the furnace is not heating 92-20802-128-03, p. 4.
3. If the furnace will not operate, the last of the operating instructions is to turn off the gas to the furnace by “To Turn Off Gas To The Appliance” and call your service technician or gas supplier 92-20802-128-03, p. 4. The steps, with the manual’s warning to turn off electrical power before removing the front access door 92-20802-128-03, p. 7, are under shutting the furnace down.

The owner’s manuals do not mention the display or its codes (92-20802-128-03; 92-20802-130-02).

When to call a licensed technician

• The furnace will not operate. The owner’s manual’s step is to turn off its gas and call your service technician or gas supplier 92-20802-128-03, p. 4.
• A code replaces the 0. Read it with the rows for your series; pages for 57, 45, 22, 93, 61, 66 and 68 are linked from the Rheem and Ruud code list.
• Anything past the filter: the owner’s manuals leave routine maintenance to a qualified installer, service agency or the gas supplier 92-20802-128-03, p. 7.

Notes for different models

Series	Where	Wording	Source
92P, 92T, 95P, 95T, 96P, 96T, 801S, 801P, 801T, 802P	code list	“STANDBY”	92-24161-111-17, p. 87; 92-24161-122-12, p. 88; 92-24161-144-09, p. 39; 92-24161-146-05, p. 40
92P to 96T 2017 revisions, 96V, 97V, 98V, 802V, 801T Ultra Low NOx	normal operation code card	“STANDBY MODE”	92-24161-111-17, p. 87; 92-24161-124-12, p. 111; 92-24161-164-01, p. 32
96V	diagnostics chart	“System Off, Standby Mode no Thermostat Calls or Errors.”	96V-chart
97V, 98V	diagnostics chart	“System Off, Standby Mode No Thermostat Call Or Errors”	97V-chart
Fault code label 92-103343-01-00 (listed on the RGGE and RGJF support pages)	label, no models printed	“Standby”	92-103343-01-00, p. 1

The 801T Ultra Low NOx card title was read from the page image 92-24161-164-01, p. 32. On the diagnostics charts 0 has fault level 0, which the 97V chart defines as “Status (No Fault)” (96V-chart; 97V-chart). The troubleshooting legends in the installation instructions print standby as the letter O, while the code lists use the digit 0 92-24161-144-09, pp. 39, 50.

On the communicating furnaces the mode letter follows the thermostat’s demand: a first-stage call shows h even though the furnace ignites at high stage 92-24161-124-12, p. 92. The green LED blink legend of the RGPN, RGPS, RGLN and RGLS instructions has no 0; its codes are blink counts (92-24161-38-12, p. 39; 3 blinks, 2 blinks).

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

• H “GAS HEAT ON”
• h “LOW GAS HEAT ON”
• C “COMPRESSOR ON (COOLING OR HEAT-PUMP HEAT)”
• F “CONTINUOS FAN ON”

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

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