What’s the Difference Between a Barometric (Parametric) CIS Tank and a Regular Ink Tank System?

Question:
I’ve heard the term “parametric tank” used in printer setups. Can you explain the difference between a parametric (or barometric) Continuous Ink Supply System (CIS) tank and a regular ink tank?

Answer:
Thank you for contacting us, and we sincerely apologize for the delay in getting back to you. We know how important it is to understand your printer system setup, and we want to make sure we give every question the thoughtful and detailed response it deserves. We at BCH Technologies are grateful for your engagement and support, especially through our YouTube channel (https://youtube.com/@bchtechnologies). Your feedback is instrumental in helping us expand our technical content and support resources for the entire printing community.

Now, regarding your question, this is a great one. It often comes up when customers are setting up or modifying their printers for continuous ink systems.

🔍 Barometric (Parametric) CIS Tanks: How They Work

A barometric or parametric CIS (Continuous Ink Supply System) tank is an external ink tank system that relies on atmospheric pressure and gravity to regulate ink flow. It does not use internal vacuum pressure or active pumping, making it a passive yet highly effective delivery system.

Here's a breakdown of how this system functions:

• The setup consists of two parts per color: a large reservoir and a small barometric chamber.

• The tank system is vented to the atmosphere through a small air hole—this balances internal and external pressure.

• As the printer uses ink, a small vacuum forms in the line, causing ink to draw from the large tank into the barometric chamber.

• The barometric chamber regulates the pressure so the ink doesn’t free-flow or siphon, even when full.

• The ink will only flow if the printhead is situated between the ink levels of the large and small tanks.

  • If the printhead is above the large tank, ink may flow backward into the tank.

  • If the printhead is below the small tank, gravity may cause ink to flood the printhead.

This self-regulating system allows for stable ink flow without the need for dampers at the cartridge or head end. It’s especially useful for pigment or dye-based ink setups where consistency is critical.

We have a detailed explanation and primer guide on barometric tanks, which you can read here:
How to Prime CIS Tanks (https://bchtechnologies.com/blogs/news/how-to-prime-cis-tanks).

🧪 Regular (Non-Barometric) Ink Tanks

In contrast, regular ink tanks are just containers holding ink—these don’t rely on atmospheric balancing. Instead, they require a one-way damper to regulate the ink flow. These systems are common in DTF white ink setups, where flow control is vital to prevent backflow or ink starvation.

Regular tanks can be as simple as a mason jar with a tube connected to your printer. The control mechanism is the damper—specifically, a real one-way damper like the BCH V2 top-load dampers, which you can find here:
Improved V2 Top Load White Ink Damper
(https://bchtechnologies.com/products/improved-version-2-top-load-white-ink-damper-for-dtg-dtf-fits-most-models-l1300-l1800-l300-l350-l355-l550-l801-l800-l850?_pos=3&_sid=520a2f914&_ss=r)

⚠️ Important Note:
The word damper is used loosely in the industry, and many components labeled as "dampers"—especially in EcoTank printers—are not true one-way valves. For controlled systems like DTF white ink, it's essential to use verified dampers that prevent backflow and allow ink to flow only in one direction.

Printer setups and modifications often involve physical and pressure-based mechanics, making them tricky to diagnose or resolve without hands-on access. That’s why we can’t offer remote repair or troubleshooting services. However, if you're local, we do provide in-person diagnostic and repair services through our repair facility (https://bchtechnologies.com/printer-repair-service). Please be aware that service is offered on a first-come, first-served basis, and due to high demand, it might take a few weeks for availability.

Our repair offerings can cover full printers or individual components, and we’ll guide you through your options. If you'd rather tackle the problem yourself, we recommend starting with online tutorials. Visit our YouTube channel homepage (https://youtube.com/@bchtechnologies) and use the search icon next to the “About” tab to find videos on your specific topic. Given that we’ve produced hundreds of videos over the years, using YouTube’s built-in search tool is the most effective way to find exactly what you need—and you might also discover helpful content from other creators.

Thanks again for your question and for using our products—we’re always here to support your journey into the world of precision printing!