Lennox · Furnace

E272 Soft lockout - recycles exceeded, pressure switch opened

High severity EL296UHVLennox SL280UHVLennox ML180UHELennox SL297NV

What the control is telling you

Last recycle was due to the pressure switch opening.

Applies to: EL296UHV(X) series furnaces (integrated control 103130-XX and 107045-XX)

Likely causes

  • Low switch stuck closed at start
  • High switch not closing
  • Vent or inducer problem

Test and repair steps

  1. Check whether the low pressure switch is stuck closed at start of the heat call.
  2. The control checks that the pressure switches are open before the inducer starts; a switch closed at that point blocks ignition.
  3. Check high pressure switch closing on a heat call.
  4. Measure operating pressure with a manometer and compare to the set-point tables.
  5. Inspect the vent, intake and inducer for restriction or improper operation.
  6. Check the condensate trap and the condensate hose screens at the cold end header box for blockage (power off; twist and pull screens, rinse); prime the trap with 10 fl. oz. (300 ml) of water if dry. If furnace and coil drains are combined, the A/C drain must be vented or the pressure switch will not work properly.
  7. Warning: Never bypass the pressure switch.
  8. Clears when a heat call completes successfully.

Settings for these units

Recommended filter size by cabinet width · EL296UHV

Cabinet widthSide returnBottom return
17-1/2 in.16 x 25 x 1 in. (1)16 x 25 x 1 in. (1)
21 in.16 x 25 x 1 in. (1)20 x 25 x 1 in. (1)
24-1/2 in.16 x 25 x 1 in. (2)24 x 25 x 1 in. (1)

Number in brackets is the quantity of filters.

Filters are field supplied and installed outside the furnace; inspect monthly.

Recommended filter size by cabinet width · Lennox SL280UHV

Cabinet widthSide returnBottom return
14-1/2 in.16 x 25 x 1 in. (1)14 x 25 x 1 in. (1)
17-1/2 in.16 x 25 x 1 in. (1)16 x 25 x 1 in. (1)
21 in.16 x 25 x 1 in. (1)20 x 25 x 1 in. (1)
24-1/2 in.16 x 25 x 1 in. (2)24 x 25 x 1 in. (1)

Number in brackets is filter quantity; filters are field supplied.

Never run the unit without a filter installed.

Models that show this code

34 models in EL296UHV, Lennox SL280UHV, Lennox ML180UHE, Lennox SL297NV

EL296UH045XV36BEL296UH070XV36BEL296UH090XV36CEL296UH090XV48CEL296UH090XV60CEL296UH110XV48CEL296UH110XV60CEL296UH135XV60DML180UH045E36AKML180UH045XE36AKML180UH070E36AKML180UH070E36BKML180UH070XE36AKML180UH070XE36BKML180UH090E48BKML180UH090E60CKML180UH090XE48BKML180UH110E60CKML180UH110XE60CKML180UH135E60DKSL280UH060NV36ASL280UH070V36ASL280UH080NV48BSL280UH080NV60CSL280UH090V36BSL280UH090V48BSL280UH090V60CSL280UH100NV60CSL280UH110V60CSL280UH135V60DSL297UH040NV36BSL297UH060NV36BSL297UH080NV48CSL297UH080NV60C

Other codes on the same units

  • E250 Limit switch circuit open
  • E252 Discharge air temperature too high
  • E270 Soft lockout - no flame after max retries
  • E271 Soft lockout - retries exceeded, pressure switch opened
  • E273 Soft lockout - recycles exceeded, flame failure
  • E274 Soft lockout - limit opened
  • E275 Soft lockout - flame out of sequence, now gone
  • E276 Watchguard calibration failure

Save it for the next call

Star this code in the HVACopedia app and keep the whole library on your phone for jobs with no signal.

Open the app

Source: Lennox EL296UHV(X) Unit Information / Service Literature, Table 5 Ignition Control 103130-XX Diagnostic Codes, p.36; Ignition Control 107045-XX Diagnostic Codes table, p.43, Troubleshooting: Heating Sequence of Operation flowchart, p.110-112. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.