Replacement for AFMD35121 Furnace in 2018 Keystone Cougar 27SAB
Updated 12/15/2025 | Published 11/11/2024
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Question:
what is the replacement furnace for an AFMD35121 from a 2018 keystone cougar 27SAB?
asked by: Harvey B
Expert Reply:
Hi Harvey; the DFMD35 series (same as your AFMD35121) has been discontinued. This leaves you with two options. You can either downsize to a 30k Btu unit or move up to the 40k unit. The 30k will fit in your existing space but you will have a little less heat.
If you go up to the 40k unit it will probably require enlarging your opening since it is 2" taller. You also need to match door for door or doorless for doorless when choosing the replacement. The 40k units measure 20" deep x 9" tall x 16-1/2" wide and cutout varies based on the door as seen below.
You can choose from the following based on Btu, door/doorless, and door color:
-Dometic RV Furnace - LP Gas - Automatic Pilot - 12V DC - 30,000 Btu - White Door # DMC98RR
-Dometic RV Furnace - LP Gas - Automatic Pilot - 12V DC - 30,000 Btu - Black Door # DMC38RR
-Dometic RV Furnace - LP Gas - Automatic Pilot - 12V DC - 30,000 Btu - Doorless # DMC54RR
-Dometic RV Furnace - LP Gas - Automatic Pilot - 12V DC - 40,000 Btu - White Door # DMC68RR
-Dometic RV Furnace - LP Gas - Automatic Pilot - 12V DC - 40,000 Btu - Black Door # DMC48RR
-Dometic RV Furnace - LP Gas - Automatic Pilot - 12V DC - 40,000 Btu - Doorless # DMC72ZR
(click to enlarge)
(click to enlarge)
Product Page this Question was Asked From
Dometic RV Furnace - Propane - Automatic Pilot - 12V DC - 30,000 Btu - White Door
- RV Furnace
- Doored
- 5th Wheel
- Motorhome
- Travel Trailer
- 30000 Btu
- 16-1/2W x 7T x 20D Inch
- White
- Dometic
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- Article: Thank you!
Robin H.
12/15/2025
Hi Harvey, how did things go with replacing the AFMD35121 furnace in your Cougar? Did you end up choosing the 30k or the 40k Dometic model for your setup? Your update could make it easier for others facing the same decision.