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Testo 550i I App Operated Digital Manifold for air Conditioning, Refrigeration Systems and Heat Pumps – with Bluetooth

  • Based on 121 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Monday, Nov 17
Order within 9 hours and 38 minutes
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Style: Digital Manifold


Features

  • Dependable: The testo 550i with its rugged housing (IP54) was particularly created for harsh environments, offering the reliability needed by HVACR technicians
  • User-friendly: With its compact design, 2-way valve block and automated probe connection, the HVAC meter provides convenient handling in difficult to access environments
  • Smart App: Take advantage of clearly visualized documentation from a smartphone or tablet. Remotely operate service and maintenance tasks and send results directly from the job site
  • Efficient: The wireless manifold determines high and low pressure as well as evaporation and condensation temperature. Optionally add suitable accessories for an enhanced performance
  • Accurate: Thanks to its unique measurement technology and extremely sensitive pressure sensors, the air conditioning meter achieves particularly quick and easy measurements

Description

testo 550i – Remote and accurate measurements via App Installation and maintenance of air conditioning, refrigeration systems and heat pumps has never been more convenient. With its durable, metal 2-way valve block, rugged housing, suspension hook and extremely compact format, the manifold is ideal for harsh working environments. Keep your refrigerants up to date and accurately measure high and low pressure along with evaporation and condensation temperature. The automatic connection to Bluetooth probes achieves flexible and easy measurement of a variety of parameters. Operated via app, the wireless HVAC instrument offers remote measuring and monitoring of data with a clearly structured visualization. Results can quickly be stored and sent directly from the job. Technical Data Temperature measuring range: -58° to +302°F / - 50° to +150°C Temperature measurement accuracy: ±0.9 °F / ±0.5 °C Pressure measuring range: -15 to 870 psi / -1 to 60 bar Pressure measurement accuracy: ±0.5 % of full-scale value Vacuum measuring range: -15 to 0 psi / -1 to 0 bar System requirements: requires iOS 7.1 or newer; requires Android 4.3 or newer; requires mobile end device with Bluetooth 4.0 Scope of Delivery: ✓ testo 550i including instruction manual, calibration protocol and batteries

Product Dimensions ‏ : ‎ 3.03 x 4.29 x 2.36 inches; 1.31 Pounds


Item model number ‏ : ‎ 550i


Batteries ‏ : ‎ 3 AAA batteries required. (included)


Date First Available ‏ : ‎ January 25, 2021


Manufacturer ‏ : ‎ Testo SE & Co. KGaA


Best Sellers Rank: #194,440 in Industrial & Scientific (See Top 100 in Industrial & Scientific) #260 in Indoor Air Quality Meters


#260 in Indoor Air Quality Meters:


Customer Reviews: 4.3 4.3 out of 5 stars 121 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Nov 17

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
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  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Great tool for HVAC techs
Style: Temperature and Humidity Kit
Pretty easy to use. Easy to set up. I loaded the Testo app on my phone and on a cheap tablet (both are android devices). The app worked perfectly on both. The clamps and thermohyrgometers connected instantly to my phone and tablet.
Reviewed in the United States on July 20, 2025 by DRod

  • More must have HVAC tools
Style: Temperature Kit
Best money I’ve spent, high quality tool and built to last.
Reviewed in the United States on May 29, 2025 by Keith Holt

  • Excellent quality and a good price.
Style: Temperature Kit
I purchased and returned several sets of gauges, both analog and digital before landing on this Testo set. These are the real deal. Easy to use and very accurate. There are some good looking china copycats that seem to be loaded with features but they fall flat in use and have horrible documentation and support. Testo is what you would expect with German made products and they do deliver all the way around. The interface is easy to use and read and each item is durable. There is no reason to buy "big yellow" when these are such a better deal. Nobody has more wireless sensors than these guys either. ... show more
Reviewed in the United States on September 4, 2023 by RV Patriot

  • Great setup
Style: Temperature and Humidity Kit
Absolutely love this set up testo came up with got so tired of buying lens covers for the yellow jacket guages. Absolutely love all the accessories purchased as well can keep up with all pressures temp differences and send it to a customer with the invoices. Couldn't beat the prices i paid at any local hvac wholesalers ... show more
Reviewed in the United States on October 16, 2024 by Dennis K Pitts

  • Very poor quality – not professional at all
Style: Temperature Kit
The app is unstable and constantly crashes. The clamps feel cheap and unreliable, the materials are low grade, and the “gauges” are not real gauges but tiny whistles that are completely useless for proper diagnostics. This is not professional equipment, just an overpriced toy. On top of that, I was charged a fee for the return. Totally unacceptable. ... show more
Reviewed in the United States on September 11, 2025 by Aleksandr

  • Fantastic Entry-Level or Primary Digital Manifold
Style: Digital Manifold
With six years of experience in the HVAC/R industry, I've had the opportunity to work with various tools and equipment. Recently, I acquired the Testo 550i manifold and have been evaluating its performance. Connectivity and Compatibility The 550i connects seamlessly to my iPhone and iPad, allowing for convenient data monitoring. However, I was initially disappointed to find that it's not compatible with the Testo Smart Probe app. Fortunately, the new Testo Smart app is similarly intuitive and user-friendly. Accuracy Assessment I compared the 550i's pressure readings to a Fieldpiece manifold and two Testo 549i units. The results showed a deviation of only two tenths of a psi on both high and low sides, indicating acceptable accuracy. Design and Build The 550i's compact design facilitates easy handling and storage. Its robust construction suggests durability and resistance to regular use, which is essential for a tool that's frequently used in demanding environments. Conclusion Based on my experience, the Testo 550i manifold demonstrates satisfactory performance, accuracy, and design. Although compatibility with the Testo Smart Probe app would be beneficial, the new Testo Smart app is a suitable alternative. Overall, the 550i is a reliable option for HVAC/R professionals seeking a high-quality manifold at a low price point. ... show more
Reviewed in the United States on August 23, 2024 by Robert

  • The one.
Style: Digital Manifold
I’ve had digital gauges for over 20 years and actually quit using testo over a decade ago because I didn’t have stock in Duracell. These are awesome. Small , accurate and even an old school guy can link them to my phone and use them zero problems. Case is aluminum which I found out because I already put a gash in them but so far they appear to be bullet proof. ... show more
Reviewed in the United States on June 13, 2024 by CW

  • Very nice
Style: Temperature Kit
Durable I have the probes too and a set of 550’s, depends on what I’m doing, but worth the money, good stuff
Reviewed in the United States on May 30, 2023 by Tom D Root

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