The best HVAC multimeter is by no doubt one of the must have hvac tools for a technician to keep on hand.
Their versatility is great when it comes to the troubleshooting and diagnosing of issues with HVAC units, appliances and electrical devices. They can even be used to test for faults with extension cords or to test the circuits running to light switches!
One of the main benefits of having the best HVAC multimeter is that it saves you from having to purchase and carry along different devices for performing different tests which take up more space in your kit that could be used for other tools and equipment.
What is a HVAC Multimeter?
A multimeter is a device that technicians will use to gauge certain information about HVAC units, appliances and other electrical devices.
They’re so useful because they give you the ability to measure a range of important metrics that include frequency, temperature, capacitance, resistance, voltage and current as well as a whole plethora of other useful information.
But the kind of information that you can draw from the device and the features that come with the best HVAC multimeter does depend on the model you choose.
Some are more specialized than others and there is quite a difference in quality and reliability between them too.
This article discusses the differences between the best HVAC multimeter models on the market to give you an idea on which is the most efficient, which has the best performance and which give the most relevant readings to suit to kind of job that you want it to help you with.
The first multimeter we’re going to have a look at is a Fieldpiece multimeter.
Yes, this is the much loved Fieldpiece HS36 which is practically an enhanced Fieldpiece HS33.
It is a well built, durable and user friendly piece of equipment that has all you need for testing and troubleshooting electrical devices.
The best feature on this multimeter which is not found on many others is its auto ranging feature. The fact that itis quick and accurate really makes your job so much more efficient and easier.
However, not everyone does like having an autorange and if that’s not for you, there’s plenty of other features to rave about.
The screen is lit by a bright blue backlight so you can see the readings, even if you’re working in the dark. It also has a magnetic hanger so you can put it somewhere within sight to free up your hands whilst probing, taking notes or doing something else.
It comes with detachable silicone test leads with a crocodile clip probe which is highly durable and allows you to operate it with one hand, so that your other hand can be free for multitasking.
What’s more is the dial is very tactile, you can tell when has switched between the selections and on top of it all, it comes with a neat carrying case to keep all of the components organized.
Just like many multimeters these days, a beeper is included for circuits that are over 30v to indicate whether it’s an open or closed circuit; a handy feature to have. What’s more is that it can measure in microamps! This allows you to get a more detailed view on the system your testing and to gauge a flame diode current.
It is certainly the best HVAC multimeter that you can get your hands on, a brilliant Fieldpiece multimeter that can even read a 400mf capacitor.
The UEi Test Instruments multimeter has so many applications and features for all of your circuit and appliance testing needs.
Just like the Fieldpiece HS36 Multimeter it has a brightly backlit display and a magnetic hook so you can place the device down and still read while being hands free!
It can read temperatures, test capacitance, measure voltage, frequency and resistanceof up to 40 mega ohms.
It can also perform a diode test and continuity. This is altogether a fantastic piece of equipment to include in your HVAC tool bag.
What makes this multimeter even handier is that there is storage for the test leads and has a durable crocodile clip style probe included. The dial is clear to see which setting you have on as it clicks into place and there is ample space between the selections.
This device is also able to tell you true RMS, has a work light built into it and auto-off to save battery life as well as many other great features that makes it well worth checking out!
This Clamp Fieldpiece multimeter is compact, has an easy to read screen and a high temperature resistance meaning that dramatic changes in temperature do not alter the thermometers accuracy.
Although it is a lesser product than the fieldpiece HS36, it is a more affordable alternative and still has all of the functions that a HVAC technician would use on a daily basis.
This meter can measure volts in AC/DC, temperature, resistance of up to 40 Mega Ohms, temperature and also gives true RMS readings giving you the heating potential of a particular voltage.
It has an auto select mode with which you just use the dial to set this mode up, connect the leads to the device or circuit you are interested in testing and the device will do the rest, giving you the most appropriate measurements.
Being compact it takes up little space in your inventory and having a clamp and a swivel magnet gives you the opportunity to work the meter hands free, which is always a great feature to have. The low battery indicator is useful too. This device takes 1 x 9 volt battery.
It’s compact, effective and athough it does have a limited array of functions, it does what a HVAC technician will need it for for the majority of the jobs they will encounter.
Desite it being such a simple tool, this Fluke HVAC multimeter is highly accurate and can give readings on AC currents to 400 amp, resistance to 4 kilohms, AC/DC voltage to 600 v.
The hook is highly sensitive and can measure in a conductor up to 30mm without disturbing the circuit. It’s a comfortable tool to use too, the button to open and shut the hook (or jaw) is not too small and offers good resistance unlike other multimeters out there.
What Makes The Best HVAC Multimeter?
As you can see from the multimeter choices above, there are some clear differences in between the products.
They have varying qualities and characteristics that can distinguish one from another which can be a pain when deciding on the one that will work best for you.
Ask yourself when deciding on the best HVAC multimeter, what’s most important to you?
I believe any technician would want the most reliable device that can give relevant information for the most reasonable price.
With that in mind, here’s some features, functions and qualities that determine whether or not the device is worth your money:
A clear, backlit, LED display that’s easy to read, even from an angle is such an advantage for a multimeter to have.
You may sometimes find yourself working in dim light or even no light and wouldn’t be able to do much without a backlit screen.
On cheaper devices, the wires connecting to the probes can become damage overtime and even sometimes come completely loose!
The probes of a decent multimeter will be built to last so you don’t have to replace them too often.
This is when the multimeter automatically changes its range to determine the voltage for you. This is great as it requires little input from yourself and is basically automating your work making it easier and quicker.
As mentioned above in the Fieldpiece HS36 review, not everybody likes or trusts autoranging and find in some multimeter models that it is inaccurate.
Tactile Range Selection
This refers to the dial or knob that you use to switch between the different ranges and modes that you’ll use. With some multimeters, the dial turns too smoothly that you’re not sure if it has actually selected the mode you want.
Ideally the dial would have some resistance and has a tactile and audible “click” that lets you know that it has switching form the last setting to the current one so you know where you are and you will be able to tell if the device is working.
A huge concern for those looking for the best hvac multimeter but who also wants to get the best value for their money is the accuracy of the product.
Stick to recognized and highly rated brands such as Fieldpiece and Fluke which I and many others recommend for their high quality products if you are ever unsure.
Compact & Portable
The HVAC multimeter is used by tecnicians very consistently. The more lightweight and portable it is, the more space it saves in storage and the easier it is to work with.
Sometimes bulkiness comes with more features though and a choice you will need to make is whether you want to sacrifice portability for more information displayed.
HVAC multimeter Features & Functions
Some of you may be new to the HVAC industry and just starting out on your career journeys. Others may have a wealth of experience with multimeters and just want to check they are not missing out on anything.
Eitherway, here are the basics you need to know when using your multimeter for HVAC purposes as well as some common features in multimeters that are designed to make your life easier.
You wont get far without being able to measure both AC and DC voltage.
A standard HVAC multimeter would be able to read up to 300V but ideally, so that you are prepared for all situations, have the best HVAC multimeter on hand to read up to at least 600V.
Pay attention to the increments that it measures to. Ensure your multimeter can measure in increments of 1mV for more accuracy.
The resistance of a circuit can indicate to you whether or not a system is working properly.
Resistance is measured in Ω (Ohms). You’ll want your multimeter to measure up to 5000KΩ (Kilohms) or 5MΩ (Megaohms) and to be able to measure in increments of 1/10Ω.
Amperature is the measurement of the electrical current that could be running through a wire or other components which is measure in A (Amps). This can be used to check if a wire or component has a current that’s too far under or over its capacity.
Having a multimeter that can measure up to 300A would be fitting for most residential HVAC work but for more heavy duty units, higher values would be required.
Continuity is used to determine whether the circuit is closed or open and most multimeters have a sound based function that beeps when the circuit is closed.
To check your multimeter: switch your multimeter onto this mode. On some multimeters it is paired up with the Ω resistance function (the multimeter is smart enough to know what you are trying to do), on others it is a separate function.
Cross the probe heads together and your multimeter should make a beeping sound.
Some multimeters, usually the more expensive ones, microamp readings are available which allow you to obtain much more accurate measurements of the current.
This is especially useful for very low capacity components and wires.
This is an especially useful function for HVAc technicians as it’s quite common for the capacitators in HVAC units to have a fault, causing a breaker trip and a failure in the compressor.
Being able to test the capacitor and diagnose this issue.
Sometimes its useful to be able to get accurate temperature readings on specific components within a HVAC unit.
The best HVAC multimeter choices give you the ability to ready the temperature from the device, saving you from having to carry a separate thermometer.
True RMS (root mean square) allows you to measure AC which is suaully measured on an expensive oscilloscope.
The true RMS feature gices readings in sinusoidal (sine) waves and nonsinusoidal waves.
True RMS is an accurate means of obtaining the DC value of an AC wave form.
Auto ranging ones of the features that makes the best HVAC multimeter despite some people preferring not to use it at all. It’s still great that the option is there for those who do need it or like to have it as an option.
Auto ranging detects where the range is on the measurement scale so you don’t have to waste time trying to determine that yourself so it is definitely handy to have.
I can’t stress enough how important having a back lit screen is. Working in the dark is hgihly frustrating, especially if you are working on an outdoor unit or in a crawl space with little lighting.
It’s just so valuable to be able to take your readings without having to juggle around with a torch in one hand, probes in another making your stressful and take longer.
Just like having a back light in dark environments, having a magnetic hook frees up your hands so that you can work more efficiently.
It not as necessary to have as the back light but it is still something you couldn’t live without if you already have it.
There often comes a time when you get distracted by another task, rest your multimeter down and forget about it; draining its battery.
Auto-off turns the multimeter off after a period of no use saving its battery life.
HVAC Multimeter FAQ
- Can’t I use any Multimeter for HVAC?
There are many multimeter options on the market but not all of them are the best HVAC multimeter and there are a few reasons for this.
The units that HVAC technicians service have certain amperage, voltage and resistance ranges that would fry a less specialized multimeter.
Just like a multimeter for an electrician, the best multimeter for HVAC is fit for purpose and has the capacity to have certain amperage’s run through it without fusing.
- Which is Better: Digital vs Analogue Multimeter?
The best multimeter for HVAC is going to be digital. They just have higher accuracy, more features and are able to display multiple results on one screen. Not to mention the auto ranging they can feature.
I’m sorry to say to those old school analogue advocates, but digital is just by far a more reliable choice.
- What is the Best Multimeter for Beginners?
For those that are new to the trade and just want to get some practise in, I don’t recommend spending more than you need to.
Even though the Fieldpiece HS36 or HS33 are attractive pieces of kit, you are unlikely to be using all the features that they have.
I would highly recommend the Fluke multimeter – Fluke 323 or Fluke 116 as they are simple, compact and easy to use. Perfect for a beginner HVAC tech.
- What is the Min/Max Mode?
This mode allows you to see the highest and/or the lowest readings that the HVAC measures on the component or circuit usually alongside their time stamp.
This gives you an idea of any trends that are occurring to better enable you to diagnose issues.
- What are the CAT levels?
The CAT levels are safety features that prevent your multimeter from receiving a current larger than it can handle.
They are ranked between Cat I to CAT IV and normally cheaper devices with lower capacities are ranked at CAT I.
- Why do some Multimeters have a clamp but others don’t?
The clamp which is sometimes retachable is an alternative to using the probe and is for measuring larger current carrying cables.
The spring loaded clamp multimeter hooks around the cable you are interesting in measuring and you can obtain your readings this way.
About the Author
Dave Miller is a HVAC technician with over 10 years in the industry. Dave created HeatTalk with the ambition for it to become a resource for individuals looking for answers, whether they be a layman, student or a professional.