Heat Exchanger Testing

At Unison, we specialise in non-destructive heat exchanger integrity and holding time testing. Our innovative solutions enable your company to test key heat exchangers quickly and effectively, by utilising cutting-edge technology to reduce the risk of product contamination and costly recalls. 

Our patented HEIST™ and Pastest+™ systems are the most advanced integrity testing methods on the market. Our mission is simple: we want to reduce your downtime, save on your costs, and protect the environment, by delivering innovative, cost-effective solutions to your everyday problems. 

Our products do not rely on outdated integrity and holding tube testing methods – we have developed a better way. Unison empowers your company to take back control, enabling quick and effective testing.





Solve your Quality Control Challenges with Pastest+™

It is a well-known fact that every pasteuriser and plate heat exchanger is vulnerable to cracks and other defects during its lifespan. 

These defects may cause severe contamination leading to health problems for consumers and a possible loss of reputation, forcing you to issue costly product recalls.

Of course, detecting these defects is necessary, but it is no easy task as it often requires the equipment to be completely dismantled, causing downtime and loss of production at a significant cost to the business. 

This is where Unison’s Pastest+™ can make a difference!

Introducing Pastest+™

Validated by Campden BRI, the UK’s leading independent food and drink research organisation, Pastest+™ is a non-destructive integrity and holding time test system for pasteurisers and plate heat exchangers.

Pastest+™ is transforming process equipment testing worldwide, resulting in substantial cost and time savings. Pastest+™ is the only system on the market that can do an integrity test and holding time verification test simultaneously.  Now, you no longer need to worry about costly production downtimes as Pastest+™ makes that time-consuming defect detection a reliable and faster process which only takes 1-15 minutes depending on the size of the equipment. This means that several of your key plate heat exchangers can be tested and back in production quicker than ever before. 

Our system only uses the process water supply, thus preventing any saline, compressed air, or chemicals from contaminating the plate heat exchanger during the test.

Pastest+™ versus other testing technologies

  1. Performs both integrity and holding time tests.
  2. Designed specifically for heat exchangers.
  3. More advanced technology than any other system (many of which are outdated and, in some cases, unreliable).
  4. Non-destructive PHE testing technology (no dismantling of plates required, and therefore minimum production disruption).
  5. Reduces downtime – takes between 1-15 minutes depending on the size of the equipment.
  6. Only uses process water to detect cracks as small as 30μs. No saline, compressed air, gases, or chemicals are introduced into the plate heat exchanger during testing.
  7. QR code with test results automatically generated with Pastest+ app. No handwritten labels and no possibility of operator manipulation or error.
  8. Stores all test and service history of each user’s PHEs directly in the Pastest+ app.
  9. Operator-friendly: compact in design and simple to use.
Pastest+™: A Seamless Testing Process

Here’s how our seamless testing process works.

Unison’s service engineers run a test on your plate heat exchanger using the Pastest+™ app and system, all without dismantling any plates and using only process water.

Capable of detecting small cracks to an accuracy of 30μs, Pastest+™ technology detects pressure increases in a closed volume of the plate heat exchanger. If a crack is detected, this will be shown on the Unison App, and a further inspection of the plate pack will be required.

Following the test, a QR code is generated and printed. Using this QR code, you can easily view the automatically generated test result details, which prevents any operator manipulation of the final results.

No more handwritten results.The Pastest+™ app automatically stores all of your test results, providing personalised access to your equipment test data. At the same time, it also saves a complete service history of all the customer’s PHEs within the app.


A Superior Testing Solution

  • Worldwide patented technology
  • Cost-effective and time-efficient
  • Performs both integrity and holding time tests
  • Designed specifically for heat exchangers
  • More advanced technology than any other system (many of which are outdated and, in some cases, unreliable)
      • Easier to use
      • No risk of introducing outside contaminants
      • Only uses the customer's process water
      • App-based recording of all data with zero risk of operator manipulation

Pastest+™ has been validated by Campden BRI, the UK’s leading independent food and drink research organisation. 

“The test was noted to be rapid,” stated researchers. “The technology was considered to be very effective for simplistic systematic testing the integrity of plate heat exchangers.”