Dometic DFLD40121

Last updated: November 3, 2026

Dometic DFLD40121

3.0/5#8 of 8 in 35,000 BTU and up RV furnaces
3.0

For a large motorhome or fifth wheel with a doorless Dometic furnace to replace.

40,000 BTUInput
DuctedDischarge

Check price at Amazon$1,155.54

Price checked November 3, 2026. As an Amazon Associate we earn from qualifying purchases.

Pros

40,000 BTU for large rigs
Doorless with a rear gas manifold

Cons

Amp draw not published by Dometic
12 V draw likely above 12 A on a big furnace

How it scores

The rating comes from 3 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.

Value $28.89 per 1,000 BTU ($1,155.54, 40,000 BTU)63
Power draw 12 V amp draw not published (neutral score used)50
Warranty warranty not published, scored as none0

Specifications

Heat and power
Model number	9108923366
Input capacity	40,000 BTU
Discharge	Ducted
Fit
Weight	35.5 lb

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Fogatti RF035AR 35,000 BTU

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The ducted version of the Fogatti 35,000 BTU furnace.

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Suburban SF-35VHFQ (2587A)

#7 in 35,000 BTU and up3.2Full review

For a 35,000 BTU swap where the RV has no exterior furnace door.

Amazon $1,230.63

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