Furnace not heating
Goodman, Amana and Daikin 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.
Goodman'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 IN YOUR BUILDING."
- "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."
Goodman, Gas-Fired Warm Air Furnace User's Information Manual, HIG-2002A (09/19), page 1
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."
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.
Goodman's own words:
- "SHOULD OVERHEATING OCCUR OR THE GAS SUPPLY FAIL TO SHUT OFF, TURN OFF THE MANUAL GAS SHUTOFF VALVE EXTERNAL TO THE FURNACE BEFORE TURNING OFF THE ELECTRICAL SUPPLY."
Goodman, Installation Instructions for *R9S80 & *D9S80*, IOG-2035C (07/2025), page 3
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 Goodman prints for that model's board, and quoted with its page. Nothing here asks you to open the furnace.
What this page reads for Goodman, Amana and Daikin
Each code is read from the table printed in Goodman's own document for your furnace's series, and quoted with its edition and page. The documents held here:
- *M9S80*U: Goodman IOG-2031 09/2021 (an earlier line)
- *M9S96: Goodman IOG-2029A 02/2022 (an earlier line)
- *M9S96*U: Goodman IOG-2032 09/2021 (an earlier line)
- *R9S80: Goodman IOG-2035C 07/2025
- *R9S80*U: Goodman IOG-2039B 01/2024
- *R9S96: Goodman IOG-2037A 09/2023
- *R9T80: Goodman IOG-2036B 12/2024
- *RVS80: Goodman IOG-2041 04/2024
- *RVS80*U: Goodman RS6621303r1 October 2025
- *RVS96: Goodman IOG-2042 04/2024
- *RVT80: Goodman IOG-2043 03/2024
- *RVT96: Goodman IOG-2044 03/2024
- DM80VC: Daikin IOD-2012H 06/2023 (an earlier line)
- DM96HS: Daikin RSD6612011r5 October 2017 (an earlier line)
- DM96SN: Daikin IOD-2029A 02/2022 (an earlier line)
- DM96VC: Daikin IOD-2008N 02/2022 (an earlier line)
- DM97MC: Daikin IOD-2007Q 08/2024 (an earlier line)
- DR80TC: Daikin IOD-2043 03/2024
- DR96TC: Daikin IOD-2044 04/2024
- DR96TN: Daikin IOD-2038A 09/2023
- DR96TN: Daikin RSD6612304 May 2024
- GM9C96: Goodman RS6612020r1 March 2023 (an earlier line)
- GM9S80: Goodman RS6621008 July 2021 (an earlier line)
- GMEC96: Goodman RS6612013r10 June 2020 (an earlier line)
- GMES80*U*: Goodman RS6621006r2 June 2020 (an earlier line)
- GMS8: Goodman RS6612006r7 November 2017 (an earlier line)
- GMVC80: Goodman RS6621004r3 October 2020 (an earlier line)
- GMVC96: Goodman RS6612010r6 November 2017 (an earlier line)
- GMVM97: Goodman RS6612015r3 April 2019 (an earlier line)
What it cannot answer yet
For these, the page says so instead of guessing:
- *R9T96, *RVM97, *R9S96-U and Daikin DR97MC: no maker-hosted manual is held
- older GMSS96, GMH8, GME8, GMH95, GMVC95 and GM9C80 furnaces
Questions
What should I do if my Goodman, Amana and Daikin 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. Goodman'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.