Suburban 261618 Water Heater Vent Cap – 3 Inch

The Suburban 261618 Vent Cap is an OEM exterior wall vent designed for select Suburban tankless / on-demand RV water heaters installed in RV sidewalls measuring approximately 2 to 3 inches thick. The vent provides the proper exterior termination for the water heater’s combustion exhaust system and is an important part of a safe, complete installation.

The 261618 is the 3-inch vent version in Suburban’s vent-cap family and is commonly used with the Suburban Advantage / Nautilus IW60 on-demand water heater.

Models It Fits

The Suburban 261618 is used with:

• Suburban IW60 Nautilus On-Demand Water Heater

• Suburban Advantage Tankless / Continuous Water Heater

• Select Suburban tankless replacement installations requiring a vent for 2"–3" RV wall thickness

Suburban’s parts documentation identifies 261618 as the vent cap for installations with 2 to 3 inch wall thickness.

Wall Thickness Fitment

Choose the Suburban vent cap based on the thickness of the RV sidewall:

• 261616 – 0" to 1" wall thickness

• 261617 – 1" to 2" wall thickness

• 261618 – 2" to 3" wall thickness

Using the correct vent length is important to ensure the water heater exhaust terminates properly through the RV exterior wall.

Replaces Older Part Number

The 261618 supersedes older Suburban vent cap number:

• 260595

Suburban IW60 parts documentation specifically directs customers from 260595 to 261618 for 2"–3" wall thickness applications.

Some current retailers may also reference 260618 alongside 261618 for the 3-inch vent application.

What the 261618 Vent Cap Does

The vent cap provides the exterior termination point for combustion gases produced by the water heater.

It passes through the RV sidewall and connects the water heater’s exhaust system to the exterior of the coach. Correct vent sizing is important because the required length depends on the thickness of the RV wall.

When You May Need a Replacement Vent Cap

A replacement may be needed if the existing vent is:

• Bent or damaged

• Corroded

• Missing

• Improperly sized for the RV wall

• Being replaced during installation of a Suburban tankless water heater

• Being changed because the original water heater installation used a different wall thickness

Estimated Install Time

Approximately 15–30 minutes, depending on access and whether the water heater or exterior panel is already removed.

Tools Required

• Screwdriver

• Basic hand tools

• Appropriate RV exterior sealant

• Tape measure for confirming wall thickness

Installation Notes

Before ordering, measure the actual RV sidewall thickness at the water heater opening.

The 261618 is intended for walls approximately 2 to 3 inches thick. If your wall is thinner, use the corresponding shorter Suburban vent cap.

Always make sure the exterior vent is properly sealed and installed according to Suburban’s water heater installation requirements.

Product Specifications

Manufacturer: Suburban / Airxcel
Part Number: 261618
Replaces: 260595
Part Type: Water Heater Exhaust Vent / Vent Cap
Vent Length: 3 Inch
Wall Thickness: 2"–3"
Material: Metal
Application: Select Suburban Tankless / On-Demand RV Water Heaters
Common Model: IW60 Nautilus / Advantage Tankless

Important: The 261618 is selected by RV wall thickness. For 0"–1" walls use 261616; for 1"–2" walls use 261617.