Suburban Furnace Bottom Duct Kit | 520576 | SF-20/25/30/35 Q/FQ

Complete your Suburban SF furnace installation with the Suburban Furnace Bottom Duct Kit w/ Gasket (Part #520576). Genuine Suburban OEM rectangular bottom duct kit — includes the metal inlay, gasket, and manual. Fits SF-20/25/30/35 Q and FQ variants and most other SF furnaces from Suburban.

What This Does

The bottom duct kit is the rectangular ducted airflow interface that mounts to the bottom of your Suburban SF furnace. When your existing bottom duct is:

• Damaged or corroded from age
• Missing entirely after a furnace swap
• Leaking around the gasket — reducing heating efficiency

...this kit provides everything needed to restore proper ducted airflow at the bottom output.

Just Need the Gasket?

If you already have the duct kit installed and only need to replace the gasket, see the Suburban Furnace Rectangular Bottom Duct Gasket (070853). Note: Suburban no longer requires this gasket for SF furnaces — it's optional.

Compatible Suburban SF Furnace Models

Fits most SF furnaces from Suburban, including:

• SF-20Q / SF-20FQ
• SF-25Q / SF-25FQ
• SF-30Q / SF-30FQ
• SF-35Q / SF-35FQ

Since Suburban builds the Furrion FFG20RA and FFG30RA furnaces on the same platform (identical to the SF-20VHQ/SF-20Q and SF-30VHQ/SF-30Q respectively), this kit is also applicable to those Furrion furnaces.

Related Furnaces

If you're servicing a compatible Suburban-built furnace:

• Furrion FFG20RA 20K BTU LP Furnace (Suburban SF-20VHQ/SF-20Q equivalent)
• Furrion FFG30RA 30K BTU LP Furnace (Suburban SF-30VHQ/SF-30Q equivalent)

What's Included

• Rectangular bottom duct kit
• Metal inlay
• Gasket
• Manual

Cross-Reference Part Numbers

• Part Number: 520576

⚠️ Professional Installation Recommended

Installation involves furnace disassembly and gasket sealing to prevent air leakage. Installation should be performed by a qualified RV service technician unless you have prior experience with Suburban furnace service.

Genuine Suburban OEM

Key Features

• Genuine Suburban OEM bottom duct kit
• Part number: 520576
• Rectangular bottom duct configuration
• Fits most Suburban SF furnaces: SF-20/25/30/35 Q and FQ variants
• Also fits Suburban-built Furrion furnaces (FFG20RA, FFG30RA)
• Includes gasket for proper sealing
• Complete kit — includes metal inlay and manual

Specifications

• Brand: Suburban
• Part Number: 520576
• Type: Furnace Bottom Duct Kit (Rectangular)
• Compatible Furnaces: Suburban SF-20/25/30/35 Q and FQ variants (fits most SF furnaces); Suburban-built Furrion FFG20RA, FFG30RA
• Included: Rectangular duct kit, metal inlay, gasket, manual
• Condition: New