Best Digital HVAC Gauges Review in 2021 – New Guide

Best Digital HVAC Gauges

LAST UPDATED: January 13th, 2021

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Regardless of whether you are a professional HVAC specialist, a tech student, or a novice handyman, there is surely one digital HVAC gauge that awaits you.

To find the best, you must know exactly what features to look for. Clearly, there is no single best product for everyone.

Each has his or her own needs and HVAC requirements. Therefore, we included single unit manifold gauge meters as well as kits complete with hoses and thermocouples.

In the next few parts of this review, we will try to provide you answers to the questions like what are the digital HVAC gauges and exactly what makes them the most reliable in the market.

Best Digital HVAC Gauges Comparison

Last update on 2021-04-17 / Affiliate links / Images from Amazon Product Advertising API

Best Digital HVAC Gauges Review in 2021

We have considered important factors, such as budget and versatile functions to find the best digital manifold gauges available in the market today. Here is an overview of each.

Fieldpiece SM480V Digital Manifold Gauge

Fieldpiece SM480V Digital Manifold Gauge

If you are searching for the best rated digital HVAC gauge that has wireless features and 4 ports, then you are already looking at your first option – the SM480V.

In this package, you will get 2 type-K pipe clamp thermocouples, a built-in micron gauge, and a padded carrying bag that allows you to easily store and transport the digital manifold gauge set.

The digital display already shows every detail and information you need. From the low side and high side pressure to the refrigerant type and the target superheat.

When it comes to its wireless features, the TSH has a wireless mode that connects and syncs to the transmitter.

With that, you do not have to observe from your attic. You can simply leave the transmitter near the HVAC and the wet bulb outside to detect and send information to your digital manifold.

The only downside is that you will need to purchase the transmitter and wet bulb combo as it is not included in the set. Despite that, the convenience of its wireless feature is worth every cent you invest!

Aside from that, it also has a micron gauge that allows you to set the desired micron level. Once the set level is reached by the vacuum, you are instantly notified as it alarms you to check.


  • Has a micron vacuum gauge that counts the micron level and notifies the user
  • 4 ports for each hose – low side, high side, evacuation, and recharging
  • Holds over 70 refrigerant types
  • Comes with reliable wired pipe clamps for suction and liquid line temperature checks
  • Automatically calculates target superheat (TSH), simultaneous superheat, and subcooling
  • Water-resistant casing – IP54 rated
  • Has data logging which can store 9 full jobs


  • No major drawbacks

Fieldpiece SMAN360 3-Port Digital Manifold Gauge

Fieldpiece SMAN360 3-Port Digital Manifold Gauge

If you are looking for another Fieldpiece manifold gauge set, the 3-port SMAN360 should be worthy of your attention!

The 3-port gauge meter already comes with 2 pipe clamps with thermocouples, one for the wet bulb and the other for the dry bulb.

It is compatible with almost over 89 kinds of refrigerant types that are downloadable through the manufacturer’s site.

When it comes to the display, there has been plenty of improvement from the old Fieldpiece unit. It already has its three modes combined into one so that you will already have every detail and information you need on the LCD screen.

You will see the pressures on the top line, the superheat and subcooling on the middle line as well as the VSAT and LSAT on the bottom line.

Other information located in the middle area of the screen includes the refrigerant type, target superheat (TSH), suction line, and liquid line temperatures.

Since the device is already digital, of course, there will be no need for you to convert and calculate. The device calculates the TSH and converts units such as Celsius to Fahrenheit and vice versa.

The notable differences between the reviewed Fieldpiece SM480V and this SMAN360 are the number of available ports as well as the wireless feature. If you are not willing to shell out extra bucks for the feature, then this is your best option.

Finally, it has a carrying bag that allows you to use the gauge set in moist areas without having to worry about damaging it.


  • Has a built-in micron gauge to alarm the user once the desired micron level is reached
  • Downloadable refrigerant types through the manufacturer’s official site
  • Versatile carry-on bag allows hose connection and full usage in moist surroundings
  • Displays all the information on the LCD screen with an optional backlight


  • It has no wireless features

Related Comparison: Goodman vs Lennox HVAC Units

BELEY Refrigeration Digital Manifold HVAC System Gauge Set

BELEY Refrigeration Digital Manifold HVAC System Gauge Set

The third on the list is a digital manifold set by BELEY. It works amazingly for installation, testing, and maintenance of HVAC systems, car air conditioning systems, fridges, and cold storages.

In this set, you will get a 3-port digital manifold gauge, 2 temperature clips or clamps, and 3 hoses as well as a bag so you can carry the entire set in one go.

The digital manifold gauge set can test pressure conditions, overheating, vacuum pressure, and leakage, as well as temperature. It is compatible with over 89 refrigerants, including common types such as R410a, R22, and R12.

Most notably, this product has its straightforward use and simple options. On the interface of the device, you will find buttons for function, unit selection, refrigerant type, as well as other general buttons.

When testing pressure, recharging, and evacuating the HVAC system, you can easily hang the device near it, thanks to its hook feature! A design borrowed from the classic analog manifold gauge set.

Aside from that, you will find a clamp-on temperature probe socket on top of the device. This is where you can plug both clamp sensors to test line temperatures.


  • Has 89 kinds of refrigerant pressure-evaporation temperature database
  • Automatic calculation of subcooling and superheating
  • Able to test the percentage of vacuum measurements and pressure leak measurements, as well as leak time speed records
  • Has multi-unit pressure conversion


  • Shutoff valves must be bought separately as they are not included in the gauge set

AUTOOL lm120 Refrigeration Digital Manifold Gauge Meter

AUTOOL lm120 Refrigeration Digital Manifold Gauge Meter

Next on the list is the 3-port Autool digital manifold gauge. It is the same device as the previous one, except there are no other components and parts that come with it.

If you are looking to replace your old gauge meter, then you are looking at a reliable alternative.
Since the previous review talked about the set as a whole, let us tackle more about the manifold gauge meter here.

This instrument boasts material integrity and durability. It is made of engineered plastic and flexible non-slip silicone housing for comfort as well as safety of use.

A reliable 32-bit digital processing unit is installed for a highly precise data acquisition and pressure reading.

It has an LCD backlight display so you can easily see the numbers and percentages.
Pressure testing ranges from –101 kPa to 6 MPa, which translates to –0.1 bar to 60 bar.

For its maximum operating pressure, the standard hose has approximately 4.12 MPa or 600 PSI with a limit pressure of 3000 PSI or 20.68 MPa.

The reason for including such information is to make sure you acquire compatible hoses to match the pressure requirements.

In addition to all that, it has built-in 89 kinds of refrigerants that comply with the standard of American NIST.


  • Compatible with over 89 kinds of refrigerants including common types such as R22, R12, and R104a
  • Made of non-slip silicone casing for ease and safety of use
  • Has a hook for hanging near HVAC systems or car bars
  • Automatically calculates subcooling and superheating


  • Since it is a single digital manifold gauge meter, you will have to purchase the hoses, probes, and clamps

Related Guide: Anemometer for HVAC Review

DLG DI-517 Digital Manifold Gauge Set

DLG DI-517 Digital Manifold Gauge Set

For beginners, here is a digital manifold gauge meter that can fit inside your pockets! Yes, the DI-517 is a pocket-friendly gauge meter that works almost as efficiently as the big guys.

In this set, you will get the 3-port digital manifold and 2 clamp-on temperature plugs.
The digital manifold is compatible with over 89 types of refrigerants, which describes how well versatile it is.

It comes with a 32-bit data processor that delivers accurate and real-time results.
Some of the functions the manifold gauge can do are to process superheating and subcooling at the same time as well as display them on the LCD screen.

Aside from that, it uses 5 different units of measurement, including kilopascals (kPa), megapascals (MPa), pounds per square inch (PSI), bars, and inches of mercury (inHg).

One of the best features of this set is it’s lightweight. Compared to models or units under the same class, it is much lighter and extra durable.

Its compact design allows for extra ease in terms of portability. It is best for newer HVAC technicians or those studying the workings of HVAC and need a small device.


  • Durable and pocket-friendly manifold gauge meter
  • It comes with over 89 refrigerant profiles
  • Indicates a low power warning on the screen to remind the user to replace batteries
  • Converts Celsius to Fahrenheit and vice versa


  • Does not come with hoses or a carrying case

Uniweld USMAN5 SmarTech Wireless Digital Manifold Gauge Set

Uniweld USMAN5 SmarTech Wireless Digital Manifold Gauge Set

If you’re looking for a reliable digital manifold gauge set complete with temperature clips and hoses, the USMAN5 is the most suitable product for you!

What’s more? You also get a wireless module that allows you to view data through Uniweld’s SmarTech App for free!

In this set, you already get a carrying bag where you can put all the necessary contents and bring them in one go.

Apart from that, you have a 3-port digital manifold gauge, 2 pairs of thermocouple bead probes and temperature clamps, approximately 5 feet of color-coded hoses in red, blue, and black.

You can choose from over 111 refrigerant types as well as create a custom list for the ones that you often use.

The fittings allow for a micron gauge connection that should notify you once the desired micron level has been reached. With this, you will not have to check the vacuum every now and then.

Apart from the mobile application to view the activities of the digital manifold, it also enables you to view verified reports of system performance data through your email in PDF or CSV files.


  • The app is compatible with iOS and Android smart mobile devices
  • Automatic calculations of superheating and subcooling
  • Enables the export of verified report of system performance data as PDF or CSV files
  • There are color indicators that alert the user if the system is overcharged, undercharged
  • Includes 10 velcro straps for an organized hose and wire management


  • The micron gauge is not included in the product

Testo 550 Digital Manifold Kit

Testo 550 Digital Manifold Kit

Another medium-framed manifold gauge meter on the list is the Testo 550. Monitoring and viewing are enabled through a mobile application available for all iOS and Android users.

This kit already provides you with a 3-port digital manifold gauge with 3 color-coded hoses and 2 pipe clamp thermocouples. All of these can be organized inside a durable suitcase that allows you to easily transport it.

One of the most notable features of this brand is its ability to connect to a smartphone or any Wi-Fi-enabled mobile device through an application.

This allows you to remotely monitor the manifold gauge as it recharges, evacuates, and tests pressure and temperature.

The perks of it do not stop there. Since you can clearly view and monitor the activities of the manifold gauge set, you can document them for future reference and also choose to receive refrigerant updates.

It is compatible with almost 60 common types of refrigerants used on many refrigeration pieces of equipment.

In addition, the manifold gauge set comes with two temperature inputs—one for superheating and the other for subcooling.

With this, you can simultaneously check the temperature and obtain calculated results for almost all types of refrigerants.


  • Medium-framed manifold gauge that comes with a carrying case for portability
  • Enables remote monitoring through a mobile application available for iOS and Android
  • Automatic calculations of superheating and subcooling
  • Compatible with over 60 common refrigerant types


  • Does not come with a built-in micron gauge

DUOYI DY517A Refrigeration Digital Manifold Gauge Set

DUOYI DY517A Refrigeration Digital Manifold Gauge Set

The final product on the list is none other than the popular DY517A. This gauge is deemed one of the most reliable digital gauges. With its simple and straightforward functions, HVAC jobs can be done without any hassle.

In this kit, you will already get a digital manifold gauge set, 3 color-coded hoses for the service hose, low and high side pressures, as well as 2 pipe clamps thermocouples. All of these can be organized in one suitcase.

The functions of the digital manifold gauge include double pressure testing, dual temperature testing of both superheating and subcooling, multi-unit switching, and multi-mode function.

When it comes to the multi-mode function, the device can perform tasks simultaneously. In addition to that, it can also display digital readouts on the screen to enable users to efficiently gather relevant information.

It is compatible with over 89 types of refrigerant already built-in in the product, so there is no need for you to download each.

Aside from all that, the manifold gauge set uses a 32-bit digital processing unit, which allows you to perform tests and gather highly precise data.

To ensure the product is operating well, it has a low battery indicator, which reminds the user of the battery life.


  • Measures double pressure and temperature at the same time and delivers converted results
  • Automatic calculation of superheating and subcooling
  • Has over 89 built-in refrigerant types
  • Comes with hoses, thermocouples, and a carrying case


  • Does not have a built-in micron gauge

What to Look for Before Buying Digital Gauges?

What to Look for Before Buying Digital Gauges

In order to save you time and money from searching and purchasing the wrong item, take a look at some of the factors and features that make the digital gauges for HVAC.


This factor is one of the most common considerations. Yet, how do we really know if a product is durable if it hasn’t stood the test of time?

When it comes to digital manifolds, one thing is for sure, poor water-resistance does not make it durable.

One of the key things that you must look at is how its housing is welded. If it is welded in one piece, you can rest assured that it will be more durable than others that are screwed together.

Ease of Use

When it comes to ease of use, you have to consider some functions that save you from doing math and all the conversions.

With that in mind, look for a digital manifold gauge set that enables automatic calculations of superheating and subcooling.

Aside from that, there should also be an option to directly convert from one unit to another, depending on your needs.

Micron Gauge

A vacuometer and a micron gauge are add-ons that you must also search for. These make your job easier and prevent you from having to check the vacuum if it reached the desired micron level. This gauge alerts and notifies you so you can leave without worries.

There are manifold gauges on our list that already have built-in micron gauges, while others may not include those or allow for a connection.

A micron gauge is not a requirement to perform a complete evacuation. However, it is helpful and makes the job more convenient if there is an alarm to remind you to turn off the vacuum because the desired micron level is already reached.

Depending on your personal preferences and evacuation requirements, you may or may not consider looking for a product that has a micron gauge.


We want to enlist almost all 111 refrigerants in the market. But let’s be honest, you might only need less than 60 of them to work on plenty of refrigeration systems.

With that, a manifold gauge that is compatible with over 89 refrigerants should already be considered as a reliable option.

Bluetooth and Wi-Fi Connectivity

Since we are talking about digital manifold gauges, a product that is Wi-Fi or Bluetooth enabled should have an edge among others that do not have it.

For your own convenience, purchase a digital manifold gauge set that will allow you to connect your mobile device to it for remote monitoring and refrigerant updates.

Imagine how easy your job will be if you can perform other tasks or activities as the manifold gauge is testing, recharging, or evacuating the HVAC systems.

With a few swipes, you can already see if the desired levels, temperatures, and pressures have already reached.

If Wi-Fi and Bluetooth connectivity seem unnecessary to you, it is advisable to at least get a product with software or local data storage features.

Get the most out of a digital device by looking for the right technological advancements that make life easier.


When it comes to the display, you will want a product with a large LCD that has a backlight feature.
It should be able to display all the information you need, from the VSAT, LSAT, TSH, and subcooling, as well as low side and high side pressure. A low power indicator is also an advantage, so you will know when to replace batteries.

Aside from those, choose a product that displays the refrigerant type so you will know exactly the type required to be used for recharging Freon.

3-port and 4-port

Similar to analog or compound manifold gauges, digital devices also come with 3 ports and 4 ports.
The only significant difference between the two is the number of hoses needed as well as the convenience of vacuum and can replacement.

With a 4-port digital manifold gauge, you will not have to replace the vacuum with the refrigerant can because they already use separate ports and hoses.

Whereas with a 3-port, you will have to switch between the two once the process is done.

Digital Gauge Sets vs Compound Gauges

We have previously released a full review of manifold gauge sets, and the reason why we are making this comparison is to help you determine which best suits your application and personal preferences.

Digital Gauge Sets

Digital gauge sets are fairly new to many HVAC technicians. Despite its accuracy, training is required to fully grasp how to operate this modern device.

It has proven its accuracy in delivering results by eliminating the process of conversions.


The advantage of a digital gauge set is its accuracy. Human error is less likely to happen because the digital display already shows pressure readings. No conversion or math is needed at all.

Instant Calculation

In addition to that, these kinds of gauges allow technicians to work on an HVAC in a speedy manner. How so? These gauges allow for instant calculations.

Meaning, you simply connect the lines into the temperature probe, and you will instantly get a calculated readout of superheating and subcooling.

Data Transfer

Finally, most gauge sets today come with wireless communication, which allows for data transfer and viewing on a mobile device.

If not, software should be available for data streaming. This allows you to look at the previous results and compare them with current ones.

Disadvantage – Requires Training

While we already live in a digital world, using new devices would require training, especially for machines that are used for diagnostic testings. The only downside of using a digital gauge set is if you are shifting from the conventional ones. This will require some training to get used to the new device.

Compound Gauge Sets

Analog or compound gauges have already proven their accuracy and stood the test of time. The manifold gauge set has been passed on from generations of HVAC professionals, and to this day, they deliver reliable readings.

Sense of Self-Satisfaction

It makes you think more. Some professional technicians love working with analog manifold gauge sets because it gives them the feeling of performing the actual job.

From the readings down to the calibrations, operating conventional pieces often gives users the feeling of being one with the machine. Since you have to convert readings to saturation temperature, it makes you analyze the issue more.

This gives them a sense of fulfillment rather than digital equipment that hands over the information directly.

Frequency of Calibration

Another advantage of using this kind of gauge is its simple pin or needle calibration. These do not have to be calibrated every once in a while.

You can do this once a year or at least once every quarter if it is being used excessively.

Disadvantage – Human Error

The only disadvantage of using a compound manifold gauge set is its vulnerability to human errors.
Often, technicians find themselves committing human errors in operating and calibrating the manifold gauge set. This is due to overlooking readings and flawed conversions.


Ultimately, the final verdict depends on your preference, as well as whether you are a newer technician or a seasoned HVAC professional.

We personally suggest that if you are starting your career, it is best to get a compound gauge. Otherwise, get a digital manifold gauge set to optimize your time on the job.

Frequently Asked Questions

How do I measure superheat and subcool with digital manifold gauges?

Simply connect the lines at the same time. Next, you can refer to the digital display of the device. Low and high side pressure and saturation readings should already be visible.

With a push of a button, you will get instant calculations of the superheat and subcool. No math needed.

What does a micron alarm in digital manifold gauges do?

It basically allows HVAC technicians to be alerted when the desired micron level is reached by the vacuum.

This frees up the workload for the user. You can set this alarm through the micron gauge that comes with most manifolds.

Why do I have to test the subcooling temperature?

The subcooling temperature needs to be tested to know whether the cycling refrigerant reaches the HVAC’s thermostatic expansion valve or not.

What happens if I put too much refrigerant in the compressor?

Compressors work harder if you put in too much refrigerant. With that, there is a higher chance of overheating, which causes the compressor to wear faster.

Which is better between the 3-port and the 4-port digital manifold gauge sets?

The extra hose in a 4-port gauge is meant for the vacuum. With that, there is no need to switch from the vacuum to the refrigerant, unlike the 3-port gauge, which only has a single service hose for both.

If switching from the can to vacuum bothers you, then it is best to get a 4-port unit. Otherwise, many HVAC professionals would also recommend 3-port units to lessen the number of hoses.

Final Words

Searching for the digital HVAC gauges can be a tedious task, especially if you are a beginner and do not know where to look or what to consider.

With that said, we advise you to set your criteria out of the critical features and important add-ons we previously mentioned. This way, you will have a clearer vision of your ideal digital manifold gauge.

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