Suburban SF-42VHFQ 40K BTU Ducted RV Furnace | Front Gas | LP

Heat your large RV with the Suburban SF-42VHFQ 40,000 BTU Ducted Furnace (References SF-42F, SFV-42F, 2591A). Top-of-line Suburban SF-FQ series ducted furnace with horizontal OR vertical installation flexibility for large RV floor plans.

⚠️ FQ Variant — Gas Connects at the FRONT

Gas line connects at the FRONT of the unit. Plan for gas line routing if your existing installation has gas connecting elsewhere.

40,000 BTU Heating for Large RVs

• BTU Input: 40,000 BTU/hr
• Direct Spark Ignition (DSI) — single-stage
• Direct Discharge
• LP propane fuel

Horizontal OR Vertical Installation

Same dual-orientation flexibility as other SF-FQ series units — fits in areas that fixed-orientation furnaces can't.

Ducting Requirements

• Supply ducts: 4 × 4" diameter
• Return air: 55 sq inches

Electrical

• Voltage: 12V DC

Wide Suburban Replacement Compatibility

• SF-35FQ, SF-35VHFQ
• SF-42FQ, SF-42VHFQ

⚠️ Replacing a Dometic DFMD/DFLD or Atwood AFMD/AFLD? Read This First

The SF-42VHFQ can also replace Dometic DFMD/DFLD and Atwood AFMD/AFLD furnaces at 35K BTU or greater (Atwood/Dometic HydroFlame 40K BTU furnaces), with two critical fitment differences:

• Width difference: Dometic/Atwood furnaces are 1" WIDER than Suburban. Plan for the 1" gap.
• Gas line side: Dometic/Atwood have gas on the LEFT side; this Suburban connects at the FRONT. Gas line will need re-routing.

What's Included

• (1) Suburban SF-42VHFQ furnace
• Vent assembly
• Mounting screws
• Installation manual
• Original Suburban manufacturer box

NOT Included: Access door (sold separately).

2-Year Suburban Manufacturer Warranty

⚠️ Professional Installation Required

RV furnace installation involves working with propane gas, 12V DC electrical, ducting, and structural mounting. Installation should be performed by a qualified RV service technician. Always leak-test gas connections after installation.

Pairs with Suburban SF Series Repair Parts

If you're servicing or restoring a Suburban furnace, consider these related repair parts:

• Igniter electrodes: Suburban 525009 (broad SF/SFV compatibility) or 525051 (SF/SFV Q and FQ specific)

Key Features

• Genuine Suburban SF-42VHFQ 40,000 BTU ducted furnace
• FQ variant — gas connects at front
• Horizontal OR vertical installation
• Direct Spark Ignition (DSI), single-stage, direct discharge
• 12V DC, LP propane
• 4 × 4" duct supply, 55 sq in return
• Replaces: SF-35FQ, SF-35VHFQ, SF-42FQ, SF-42VHFQ; Dometic DFMD/DFLD, Atwood AFMD/AFLD (35K+ BTU / HydroFlame 40K) with fitment caveats
• Includes: Vents, mounting screws, manual, in original manufacturer box
• Dimensions: 7.5" × 17" × 20"
• Weight: 29 lbs
• Backed by 2-year Suburban manufacturer warranty

Specifications

• Brand: Suburban
• Model: SF-42VHFQ
• Cross-References: SF-42F, SFV-42F, 2591A
• Type: Ducted RV Furnace
• Heating Input: 40,000 BTU/hr
• Fuel: LP (Propane)
• Ignition Type: Direct Spark Ignition (DSI)
• Stage: Single
• Discharge Type: Direct Discharge
• Gas Connection Location: Front (FQ variant)
• Installation Orientation: Horizontal OR Vertical
• Voltage: 12V DC
• Supply Ducts: 4 × 4" required
• Return Air: 55 sq inches required
• Dimensions: 7.5" × 17" × 20"
• Weight: 29 lbs
• Replaces (Suburban): SF-35FQ, SF-35VHFQ, SF-42FQ, SF-42VHFQ
• Replaces (Dometic/Atwood): DFMD, DFLD, AFMD, AFLD (35K+ BTU); HydroFlame 40K BTU — with fitment caveats
• Includes: Vent assembly, mounting screws, manual, in original manufacturer box
• Access Door: NOT included (sold separately)
• Warranty: 2-year Suburban manufacturer warranty