Dometic DFLD40121
For a large motorhome or fifth wheel with a doorless Dometic furnace to replace.
Amazon $1,153.56$1,153.56
The Dometic DFLD40121 is the better RV furnace overall, rated 3.0 to 2.2. The Dometic DFLD40121 leads on value. The Dometic DFLD40121 costs $247.18 less ($1,153.56 vs $1,400.74).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
Dometic DFMDH35111 Essential
For a long trailer or motorhome that needs 35,000 BTU and smoother starts on a weak battery or generator.
Amazon $1,400.74$1,400.74
Which should you buy?
- Choose the Dometic DFLD40121 for value ($28.84 per 1,000 BTU ($1,153.56, 40,000 BTU) vs $40.02 per 1,000 BTU ($1,400.74, 35,000 BTU)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every 35,000 BTU and up RV furnace; a clear win is highlighted. How we rank explains each one.
| Factor weight | Dometic DFLD40121 | Dometic DFMDH35111 Essential |
|---|---|---|
| Overall rating | 3.0/5 | 2.2/5 |
| Value 40% | 63 $28.84 per 1,000 BTU ($1,153.56, 40,000 BTU) | 38 $40.02 per 1,000 BTU ($1,400.74, 35,000 BTU) |
| Power draw 35% | 50 12 V amp draw not published (neutral score used) | 14 11.1 A running, 0.3 A per 1,000 BTU |
| Warranty 25% | 0 warranty not published, scored as none | 0 warranty not published, scored as none |
Specifications
| Dometic DFLD40121 | Dometic DFMDH35111 Essential | |
|---|---|---|
| Heat and power | ||
| Input capacity | 40,000 BTU | 35,000 BTU |
| 12 V amp draw | - | 11.1 A |
| Discharge | Ducted | Ducted |
| Fit | ||
| Height | - | 7 in |
| Weight | 35.5 lb | 33.5 lb |