Heat Exchanger Integrity Testing

Unison specialise in non-destructive Heat Exchanger integrity and holding time testing of all makes and models of Heat Exchangers.  Our Heat Exchanger Integrity Testing systems (HEIST and Pastest+) are the most advanced methods on the market for locating defects in a Heat Exchanger without having to open it up on site.

Leading the field with our unique, patented Heat Exchanger Testing technologies, Unison is revolutionising the way the food, liquid processing and pharmaceutical industries test their pasteurisers and plate heat exchangers by providing innovative, cost effective solutions to their everyday problems. Instead of having to rely on outdated methods of Integrity and holding tube testing, Unison empowers companies to take control of their own testing, allowing testing to be done quickly and effectively leading to reduced downtime and savings on cost.

Having tested thousands of Plate Heat Exchangers over their 80 years experience in the industry, Unison weren’t happy with the systems that were available and knew that we could develop unique solutions that would make daily self testing of Heat Exchangers possible. 

Testing on your equipment should be thorough, quick, and professional. Our expert testing services are outlined below. 

Maintenance support contracts are also available with 24/7 cover, 365 days per year.

Plate Heat Exchanger testing
with Pastest+

Unison’s Pastest+ is a non-destructive leak detection testing service for pasteurisers and plate heat exchangers. 

PasTest+ is a patented testing method which can rapidly detect small leaks in plate heat exchangers without the need to open the plate pack. Periodic testing using the PasTest+ system will reassure customers about the integrity of their plate heat exchangers, and could reduce the possibility of a product recall where product is heated or cooled by a plate heat exchanger. This rapid, accurate test allows several heat exchangers to be tested in a single day (Each takes just 1-15 minutes depending on the size of the equipment) which will reduce production downtime significantly.

PasTest+ uses only the local water supply which is pressurised and pumped through the high pressure side of the plate heat exchanger at a measured temperature. No saline, compressed air, or chemicals are introduced into the plate heat exchanger during the test. The newly released PasTest+ app allows users to accurately measure any change in pressure within the closed low pressure side, and any increase in pressure rapidly indicates the presence of a plate defect.

The PasTest+ produces rapid, accurate results and will provide our customers with the peace of mind and the necessary documentation that their heat exchanger plates are without defect, and can reduce the possibility of a product recall.

About PasTest+ PHE Testing
  • Use as a compact, handheld mobile unit or integrate into the existing system.
  • Does not require the introduction of any special or saline solutions or gases such as helium, only the facilities own process water.
  • Fast test times of 1 to 15 minutes dependent on the size of the heat exchanger.
  • Enables systematic self-testing to provide constant process integrity assurance.
  • Increase detection and early warning of defects – reducing the risk and potential cost of product recalls.
  • Back flushing ensures any small cracks are free from debris.
  • Suitable across dairy, food, beverage, brewery, pharmaceutical, bio-technology and industrial processing.
  • Validated by Campden BRI, the UK’s leading independent food and drink research organisation.
Holding Time Verification

We offer instrument calibration, product routing services, testing and training services in holding time verification.

Tank Testing

We understand the specific testing requirements of the processing industries. Our engineers are fully qualified in tank integrity testing and holding time verification testing. We provide full certification for every test.

Unison Engineering Experts in HEAT EXCHANGER Integrity Testing

Contact us for more info

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