Furnace not heating

York, Luxaire, Coleman and Champion furnace not heating? Read the code for your model

Stop first: these are not a code to look up

If you smell gas

Leave the building now. Do not touch light switches or use a phone inside. From outside, call your gas supplier, or the fire department if you cannot reach them.

York's own words:

  • "What to do if you smell gas:"
  • "Do not try to light any appliance."
  • "Do not touch any electrical switch; do not use any phone (including cell phone) in your building."
  • "Leave the building immediately."
  • "Immediately call your gas supplier from a neighbor's phone. Follow the gas supplier's instructions."
  • "If you cannot reach your gas supplier, call the fire department."

York, User's Information Manual: All Residential Multi-position Gas Furnaces - 33 in. Models, 6100761-UUM-C-1124 (2024-11-04), page 2

If a carbon monoxide (CO) alarm is sounding, or someone feels sick

Get everyone outside into fresh air now, then call 911 or the fire department from outside.

The U.S. Consumer Product Safety Commission's words (none of the furnace makers' documents held here prints what to do when a CO alarm sounds):

  • "Never ignore an alarming CO alarm! It is warning you of a potentially deadly hazard."
  • "If the alarm signal sounds do not try to find the source of the CO:"
  • "Immediately move outside to fresh air."
  • "Call your emergency services, fire department, or 911."
  • "After calling 911, do a head count to check that all persons are accounted for. DO NOT reenter the premises until the emergency services responders have given you permission. You could lose consciousness and die if you go in the home."
  • "If the source of the CO is determined to be a malfunctioning appliance, DO NOT operate that appliance until it has been properly serviced by trained personnel."

U.S. Consumer Product Safety Commission, Carbon Monoxide Fact Sheet, "What should you do when the CO alarm sounds?" (fetched 2026-09-24), page 1

If you see flame while the thermostat is not calling for heat

This is a stop condition. Do not reset or restart the furnace. Call a technician or your gas supplier now.

York's own words:

  • "Should overheating occur or the gas valve fail to shut off, turn the external manual gas valve in the gas supply line to the furnace to the off position and let the furnace cool off before shutting off the electric power supply."

York, User's Information Manual: All Residential Multi-position Gas Furnaces - 33 in. Models, 6100761-UUM-C-1124 (2024-11-04), page 8

If a reset button on the furnace tripped again after it was pushed

Do not push it again. Call a technician.

Answer the safety questions first. Then pick the brand, say what you see on the furnace without opening it, and give the model. The code is read from the table York prints for that model's board, and quoted with its page. Nothing here asks you to open the furnace.

Field brief
Stop first a gas smell, a carbon monoxide alarm, flame while the thermostat is not calling for heat, or a reset button that trips again after it was pushed: each is answered at the top of this page, before any code. before any code
The code, by model read only from the table York prints for your model's board, quoted with its edition and page. The documents held here for York, Luxaire, Coleman and Champion: 14. 14 documents
No reset step this page gives no reset or repair step, and nothing here asks you to open the furnace. A maker's reset words are shown only as the manual's words for a technician. manual's words only

What this page reads for York, Luxaire, Coleman and Champion

Each code is read from the table printed in York's own document for your furnace's series, and quoted with its edition and page. The documents held here:

  • 33 in. multi-position furnaces (TM, TL, TG, RGF, P9C, PLC): York 1010352-UUM-N-0121 (Copyright 2021 by Johnson Controls; Supersedes: 1010352-UUM-M-0120)
  • 33 in. multi-position furnaces (Y8/Z8, Y9/Z9, RL18, RG19): York 6100761-UUM-C-1124, Supersedes: 6100761-UUM-B-0423, dated 2024-11-04, Copyright 2024 by Johnson Controls
  • DGAA/DGAH: York 5165697-BUM-C-0818 (Supersedes: 5165697-BUM-B-1216)
  • TL8E/RUF18: York 6767341-UIM-A-0426, dated 2026-04-01, Supersedes: Nothing
  • TL9E: York 5894307-UIM-B-0920 (Supersedes: 5894307-UIM-A-0320)
  • TM8E: York 5594752-UIM-B-0419 (Supersedes: 5594752-UIM-A-0119)
  • TM8V: York 1034867-UIM-D-0616 (Supersedes: 1034867-UIM-C-0615)
  • TM8Y: York 5052632-UIM-D-0217 (Supersedes: 5052632-UIM-C-0616)
  • TM9E: York 6019630-UIM-F-0423 (Copyright 2023 by Johnson Controls; Supersedes: 6019630-UIM-E-1122)
  • TM9V: York 5402851-UIM-A-0917 (Supersedes: 1083294-UIM-I-0817)
  • TM9V: York 5750149-UIM-D-1219 (Supersedes: 5750149-UIM-C-1019)
  • TM9Y: York 5052617-UIM-G-0817
  • TM9Y: York 5750144-UIM-D-1219 (Supersedes: 5750144-UIM-C-1019)
  • YP9C/CP9C/LP9C/TP9C: York 1083292-UIM-F-1116 (Supersedes: 1083292-UIM-E-1016)

What it cannot answer yet

For these, the page says so instead of guessing:

  • York's newest lines (Z8, Z9, Y8, Y9, RL18, RG19): only their owner's manual's few light states are held, not the board's code table
  • 80% modulating models
  • Guardian and Fraser-Johnston furnaces

Questions

What should I do if my York, Luxaire, Coleman and Champion furnace smells like gas?

Leave the building now. Do not touch light switches or use a phone inside. From outside, call your gas supplier, or the fire department if you cannot reach them. Do not look up a code first. York's own "what to do if you smell gas" words are quoted at the top of this page, with the document they are printed in.

Why does this page ask for the model before it reads a code?

Because the same number of blinks can mean different things on different boards from one maker. The documents held here show it in several families, among them York, Goodman, Lennox, Allied and Nordyne: a count that is a stop condition on one board means something else on another. So a code is read only from the table printed for your model's series, and where two held documents for that series print one code with the same meaning (a misspelling or a unit written two ways) it is answered once and both are cited, while where their meanings differ it asks which unit you have and never guesses.

Can I reset the furnace myself?

This page gives no reset step. Where a maker's table prints reset words for a code, they are shown as the manual's words for a technician. Rheem's installation instructions print "DO NOT jumper or reset this switch" for its rollout switches. If a reset button on the furnace trips again, stop and call a technician. Nothing here asks anyone to open a door.