Suburban 180260 High Altitude Water Heater Burner Orifice #61

The Suburban 180260 High Altitude Burner Orifice is an OEM #61 LP gas burner orifice used on select Suburban SW-Series RV water heaters. This precision brass orifice is commonly used when derating a Suburban water heater for operation at higher elevations, where reduced oxygen can affect the burner’s air-to-fuel mixture.

Suburban water heaters are certified to operate without modification at elevations up to approximately 4,500 feet in the United States. Above that elevation, Suburban states that burner deration may be required to maintain proper combustion.

Models It Fits

The Suburban 180260 #61 burner orifice is used with select 6-, 10-, 12-, and 16-gallon SW-Series water heaters, including applications within the:

• SW6 Series

• SW10 Series

• SW12 Series

• SW16 Series

This includes various pilot and DSI configurations depending on the model, serial number, and burner system installed.

Suburban’s current factory parts manual lists 180260 as the #61 burner orifice and associates the surrounding burner components with 6-, 10-, 12-, and 16-gallon SW models.

What Is Considered High Altitude?

For Suburban RV water heaters in the United States:

• Up to 4,500 ft: No altitude modification is normally required

• Above 4,500 ft: High-altitude deration is required due to thinner air that produces a smaller flame

• Below 4,500 ft again: The high-altitude deration should be reversed

Suburban specifies approximately 4% deration for every 1,000 feet above sea level.

For example, Suburban gives an 8,000-foot elevation as an example where the water heater should be derated by approximately 32%.

Why High Altitude Changes Burner Performance

As elevation increases, air density decreases and less oxygen is available for combustion.

A water heater that is properly tuned at lower elevation can begin running too rich at higher elevations because the burner is still receiving the same amount of propane but has less oxygen available to burn it completely.

Improper combustion at altitude may cause:

• Yellow or lazy burner flame

• Soot accumulation

• Burner flame lift-off

• Pilot outages on pilot-equipped models

• Reduced heating efficiency

• Irregular burner operation

• Incomplete combustion

Suburban specifically warns that improper high-altitude operation can result in poor combustion and increased carbon-monoxide risk.

What the 180260 Orifice Does

The 180260 #61 orifice meters LP gas flow into the burner assembly.

When used as part of a proper high-altitude deration, the correctly sized orifice helps compensate for reduced oxygen availability by changing the amount of propane delivered to the burner.

This helps maintain a cleaner and more stable fuel-to-air mixture at elevation.

Important – Return to Standard Configuration at Lower Elevation

A high-altitude setup should not necessarily remain installed when the RV returns to lower elevations.

Suburban specifically states that once the water heater returns to an elevation below 4,500 feet, the high-altitude deration and any associated pilot adjustments should be reversed for proper operation.

This is especially important for RV owners who regularly travel between mountain regions and lower elevations.

180260 vs. Complete High-Altitude Burner Assembly

Some SW-Series applications may use a complete burner/orifice assembly rather than replacing only the individual orifice.

Suburban 525023 is a burner assembly with orifice commonly listed for:

• SW6-Series models after serial number 953401118

• SW10-Series models after serial number 953601021

Because Suburban changed burner and gas-valve configurations during SW-Series production, verify the model, serial number, and existing burner setup before determining whether you need the 180260 individual orifice or a complete burner assembly.

Signs High Altitude May Be Affecting Your Water Heater

High-altitude deration may need to be considered if the water heater:

• Operates normally at lower elevation but poorly in the mountains

• Develops a yellow or sooty burner flame at elevation

• Produces soot around the exterior exhaust

• Experiences burner flame lift-off

• Loses the pilot flame at higher elevations

• Has noticeably reduced heating performance

• Shows signs of incomplete combustion only when camping at higher elevations

These symptoms do not automatically mean the orifice needs to be replaced. LP gas pressure, regulator operation, burner cleanliness, airflow, and burner alignment should also be checked.

Do Not Drill or Modify the Orifice

The 180260 is a precision-sized #61 orifice.

Do not attempt to enlarge, drill, ream, or clean the opening with a wire, needle, or drill bit. Altering the opening changes LP gas flow and can create an unsafe combustion condition.

If the orifice is damaged or restricted and cannot be safely cleaned, replace it.

Installation Notes

Changing a burner orifice directly affects propane combustion.

Before servicing:

1. Shut off the LP gas supply.

2. Allow the water heater to cool.

3. Verify the water heater model and serial number.

4. Confirm that high-altitude deration is actually required.

5. Install the correct burner/orifice configuration.

6. Leak-test any disturbed LP gas connections.

7. Verify burner flame and combustion after installation.

Suburban recommends that burner/orifice changes for high-altitude deration be performed by a qualified dealer or service agency.

Product Specifications

Manufacturer: Suburban / Airxcel
Part Number: 180260
Part Type: LP Gas Burner Orifice
Orifice Size: #61
Material: Brass
Fuel: LP / Propane
Application: Select Suburban SW-Series RV Water Heaters
Primary Model Families: SW6, SW10, SW12, SW16
High-Altitude Threshold: Generally above 4,500 ft in the United States
Related Burner Assembly: 525023

Important Fitment Note

The Suburban 180260 is a #61 burner orifice commonly used for high-altitude SW-Series applications.

Suburban considers water-heater operation above approximately 4,500 feet to be the point where deration may become necessary. It's simple... The higher the altitude, the thinner the air which in turn means the smaller the flame. It simply doesn't create the same amount of heat. The correct burner configuration depends on the water heater model, serial number, existing gas valve, and elevation.

If the RV returns to elevations below 4,500 feet, Suburban recommends reversing the high-altitude deration for proper operation.