Rheem / Ruud furnace code 57: pressure switch stuck open

By Jason Dearmin · Last reviewed November 15, 2026 · How we check facts

Short answerRheem and Ruud furnaces show code 57 when the pressure switch is open while the inducer is running and it should be closed. On single-stage 801T and 95T furnaces Rheem calls it "pressure switch stuck open when should be closed"; on two-stage 96V and modulating 97V furnaces it is "high pressure switch open, inducer on high speed." Rheem's listed causes start with a blocked or improperly terminated vent or intake, too much vent length or too many elbows, and wind gusts.

What code 57 means on each Rheem furnace

The pressure switch proves that the inducer (draft) motor is pulling combustion gases through the vent before the furnace is allowed to light. If the switch does not close, the control will not open the gas valve. We compared code 57 in four Rheem installation manuals, which also cover the matching Ruud models:

Furnace series	Code 57 wording	Manual
(-)801T / (-)(-)80MSX single-stage 80%	Pressure switch stuck open when should be closed	92-24161-144-08
(-)95T / (-)(-)95MSX single-stage condensing	Press. switch stuck open when should be closed (described as "Pressure switch open")	92-24161-120-16
(-)96V / (-)(-)96MDV two-stage communicating	High pressure switch open, inducer on high speed	92-24161-124-08
(-)97V modulating communicating	High pressure switch open, inducer on high speed	92-24161-126-04

On the 801T, Rheem adds that if the low pressure switch does not close after 60 seconds of inducer operation, the control starts a five-minute soft lockout. On the 95T, 96V and 97V, the manuals say the inducer runs on high speed for five minutes, then turns off and tries another pre-purge, repeating until the switch closes or the heat call ends. On the two-stage 96V, if the high switch opens after the burners are lit but the low switch stays closed, the furnace drops to low fire and keeps heating.

Causes Rheem lists for code 57

The 95T, 96V and 97V manuals print the same nine causes, in this order:

Blockage or improper termination in either the inlet or exhaust vents.
The flue vent length and/or number of elbows exceeds the maximum specified.
Faulty or disconnected inducer.
Faulty control board (inducer relay).
High altitude kit not installed in areas of high elevation.
Loose or faulty wiring.
Disconnected, blocked, split or cut pressure switch hoses.
Wind gusts (sporadic).
Faulty pressure switch.

The first and eighth causes are the ones a homeowner can see. In winter, snow drifts, ice and frost can close off the plastic vent and intake pipes on a condensing furnace. Strong wind blowing across the terminations can make the switch open intermittently, which is why Rheem lists wind gusts as a sporadic cause. Everything else on the list, from hoses to the inducer relay, is a technician repair.

Related pressure switch codes on Rheem furnaces

Code	Meaning	Models
55	Pressure switch stuck closed when it should be open (96V/97V: high pressure switch closed, inducer off)	801T, 95T, 96V, 97V
44	Low pressure switch closed, inducer off	96V, 97V
45	Low pressure switch open, inducer on high speed	96V, 97V
46	Low pressure switch open, inducer on low speed	96V, 97V
65	Mid pressure switch closed when it should be open	97V
67	Mid pressure switch open when it should be closed (firing rates between 50% and 65% run at 70%)	97V

In the 96V and 97V manuals, codes 45 and 46 list almost the same causes as code 57 (the list for 45 leaves out the high-altitude kit). On a condensing furnace, also watch for code 59 (water sensed), which Rheem says is often a blocked condensate drain or trap. A blocked drain can back water into the collector box and affect the pressure switch as well.

Safety In its code 55 guidance Rheem tells technicians to remove any pressure switch bypass and treats a bypassed switch as illegal tampering. Never jumper, bypass or tape over a limit, rollout or pressure switch. If you smell gas, leave the house and call your gas utility from outside. If a carbon monoxide alarm sounds, get everyone outside and call 911.

Safe homeowner checks for Rheem or Ruud code 57

Note the exact codeWrite down the code, and on a single-digit display watch the full cycle so you know it is 57 and not 55 or 59.
Clear the outside vent and intakeFrom the ground, remove snow, ice, leaves or nests from the plastic pipes where they leave the house. Do not climb on the roof or take pipes apart.
Check for windIf the code appears only on very windy days, tell your technician. Rheem lists wind gusts as a sporadic cause and the fix may be a different termination.
Reset onceTurn the thermostat off for about 10 seconds and back on. If 57 returns, call a licensed technician to check hoses, the inducer and the switch.

Frequently asked questions

What does 57 mean on a Ruud furnace?

The same as on a Rheem: the pressure switch is open when it should be closed. Ruud U-series furnaces share Rheem's manuals, for example the U96V uses the (-)96V manual.

Can a dirty filter cause code 57?

Rheem does not list the air filter as a cause for 57. A dirty filter is more likely to cause code 22 (main limit open). Code 57 is about the vent, inducer, hoses and switch.

Why does code 57 come and go?

Rheem lists wind gusts as a sporadic cause, and in winter snow or ice can partially block the vent. If the code is intermittent, note the weather when it happens.

Sources

Installation Instructions 92-24161-124-08: 4-Position Condensing Two-Stage Communicating Gas Furnaces with ECM blower, (-)96V and (-)(-)96MDV series, Table 20 Fault Codes with Descriptions and Solutions (pp. 112-120) (Rheem (Rheem and Ruud brands)) Covers: Rheem R96V / Ruud U96V and (-)(-)96MDV two-stage communicating condensing furnaces with the dual seven-segment display.
Installation Instructions 92-24161-126-04: Upflow Condensing Modulating Communicating Gas Furnaces with ECM blower, (-)97V series, Table 19 Fault Codes with Descriptions and Solutions (pp. 95-104) (Rheem (Rheem and Ruud brands)) Covers: Rheem R97V / Ruud U97V upflow modulating communicating condensing furnaces with the dual seven-segment display.
Installation Instructions 92-24161-120-16: 4-Position Condensing Single Stage Gas Furnaces, (-)95T and (-)(-)95MSX series, section 16 Diagnostics and Fault Codes (Table 17 fault code list, Table 20 descriptions) (Rheem (Rheem and Ruud brands)) Covers: Rheem and Ruud (-)95T and (-)(-)95MSX single-stage condensing furnaces with a single seven-segment display.
Installation Instructions 92-24161-144-08: Upflow/Horizontal Single Stage Gas Furnaces, (-)801T and (-)(-)80MSX series, section 14 Diagnostics and Fault Codes (Rheem (Rheem and Ruud brands)) Covers: Rheem and Ruud (-)801T upflow/horizontal single-stage furnaces and (-)(-)80MSX upflow/horizontal furnaces with the seven-segment display control. Other Rheem and Ruud furnace series can use different controls.

Safety note: this page is general information drawn from the sources above. Gas, combustion and line-voltage repairs belong to a licensed professional. Your own equipment's label and manual take priority over anything here. Read the full disclaimer.