Understanding the Pentair WhisperFlo VST Communication Cable

If you’ve got a Pentair WhisperFlo VST pool pump—or you're thinking about upgrading—it’s natural to wonder what the communication cable is all about. Do you need it? What does it do? Can you install it yourself? We’ve got you covered with clear answers and tips to make things easy, whether you're a pool pro or a determined DIYer.

What Does the Communication Cable Actually Do?

The communication cable lets your WhisperFlo VST "talk" to a Pentair automation system like IntelliCenter or EasyTouch. It allows you to control your pump remotely, create custom schedules, and view real-time RPM and wattage usage right from your control panel or mobile app. Without the cable, your pump can still run just fine—you’ll just use the built-in keypad on top of the motor.

Do You Need the Cable?

If you’re running the pump by itself, you don’t need it. But if you're planning to automate your pool system or already have a Pentair control panel installed, the communication cable is key to unlocking all the smart features the WhisperFlo VST offers.

What Kind of Cable Is It?

The standard Pentair communication cable uses 4-conductor, RS-485 protocol wiring. One of the most common part numbers is Pentair 356324Z. You can find this cable pre-terminated and ready to install on our website or in-store.

Can You Make Your Own?

If you're confident with wiring and want a longer run than the standard 50-foot cable, you can make your own using 22 AWG shielded twisted-pair wire. Just make sure you’re using the RS-485 spec and connecting the wires properly to the COM terminals on both ends. A multimeter and a little patience go a long way here!

Where Do You Plug It In?

• At the pump: Remove the small side panel on the pump housing to access the communication port (usually marked “COM”).
• At the automation panel: Plug it into the RS-485 COM ports. These are usually labeled “Pump” or “Comm.”

Once everything’s wired up, your automation system should detect the pump automatically or allow you to add it manually in the settings.

What If It’s Not Working?

If your pump isn’t showing up in your automation panel, double-check the wiring order and ensure each device on the RS-485 network has a unique address. Power cycle both the panel and the pump. Still no luck? You might have a cable issue or a settings conflict.

Can You Connect More Than One Device?

Yes! RS-485 allows you to daisy-chain up to 8 devices on the same line. That means you can connect multiple pumps, heaters, salt systems, and more—just be sure they all have unique addresses in your automation settings.

Is It the Same Cable as IntelliFlo?

Not always. While the communication style (RS-485) is the same, the actual connectors and wiring order may differ slightly between pump models. Always double-check compatibility based on your pump and automation setup.

Where Can You Get One?

You can order the cable directly from Aqua Pool Supply:

• Pentair WhisperFlo VST Communication Cable
• WhisperFlo VST Pumps & Accessories
• Pentair Automation Systems

Helpful Tip

If you’re unsure whether your WhisperFlo VST is already connected, try checking your automation panel for any listed pumps. If it’s not there, it may just be a missing cable away from being fully integrated!

Need Help?

Our team here at Aqua Pool Supply is happy to walk you through installation or help troubleshoot your setup. We specialize in Pentair pool pumps and automation systems, and we stock all the parts you’ll need—whether you're local or ordering online.

Got questions? Reach out or stop by one of our locations in Phoenix, Scottsdale, or Las Vegas!