When it comes to car wash vacuum systems, the size of the hose you choose can make a big difference in cleaning efficiency. The two most common hose sizes—2 inches and 1.5 inches—each offer distinct advantages depending on your cleaning needs. Understanding the differences between them will help you make the best choice for your car wash business.

Hose Size Breakdown: Airflow, Suction, and Air Velocity

Think about taking a deep breath with your mouth wide open—you pull in a lot of air quickly. Now, imagine doing the same thing but with a straw in your mouth. You’re still using the same effort, but the air is being forced through a smaller opening, making it feel more powerful even though less air is moving. This is exactly how vacuum hose sizes work.

Before diving into the specifics, it’s important to understand two key terms:

• CFM (Cubic Feet per Minute): Measures the volume of air moving through the vacuum. A higher CFM means more air is being pulled in, making it better for covering large areas.
• Air Watts: Measures the actual suction power or "pull" of the vacuum. A higher Air Watts value indicates stronger suction, making it better for lifting dirt and debris from surfaces.

The bigger hose sucks more air with less pull, while the smaller hose sucks less air with more pull.

On the 3-motor single-hose stainless steel commercial vacuums we sell, a 2" hose delivers 210 CFM and 415.4 Air Watts, allowing for greater airflow. This makes it ideal for general-purpose cleaning and picking up larger debris while reducing the risk of clogging. In contrast, a 1.5" hose on the same vacuum system provides more focused suction with 165.9 CFM and 662.3 Air Watts. The smaller opening forces the same suction power into a concentrated area, increasing air velocity and making it more effective for deep cleaning carpets, upholstery, and tight spaces. While these numbers are specific to these commercial vacuums, the relationship between hose diameter, airflow, and suction power remains the same across different vacuum systems.

Best Uses for Each Hose Size

A 1.5" hose is the preferred choice for self-service car washes that want to impress customers with the strongest possible suction. Since the smaller diameter creates a more powerful, concentrated pull, customers will immediately notice how well the vacuum lifts dirt, sand, and pet hair from carpets and upholstery. Additionally, because it takes slightly longer to clean a vehicle with a 1.5" hose, customers will spend more time using the vacuum, ultimately increasing revenue per session.

For commercial fleets where porters clean multiple vehicles quickly, a 2" hose may be the better option. The higher airflow and reduced chance of clogging make it ideal for efficiently removing larger debris, allowing workers to move from vehicle to vehicle more rapidly.

A 2" hose is also a great choice for commercial car washes, especially in locations where customers may accidentally vacuum up larger debris that could clog the hose. If the hose becomes clogged, the entire vacuum system can stop working, leading to downtime and maintenance issues. The larger diameter of the 2" hose helps prevent this by allowing bigger particles to pass through more easily, keeping the vacuum running smoothly.

Which Hose Should You Choose?

If you operate a self-service car wash, a 1.5" hose will create a superior experience for customers, making them feel the vacuum is more powerful while also increasing the amount of time they spend vacuuming—resulting in higher revenue. If you manage a fleet washing operation, a 2" hose will allow porters to clean vehicles more quickly, making it the most efficient choice for high-volume environments.

For high-traffic commercial car washes, a 2" hose is highly recommended to minimize clogs and keep the vacuum system running at full efficiency. This ensures customers can continuously use the vacuum without frustrating downtime or maintenance issues.

Both hose sizes serve a purpose, and having both in your car wash setup ensures you can tackle any cleaning challenge effectively. Need help selecting the right vacuum system for your business? Contact us today for expert recommendations!