If you're trying to maintain an HVAC system without a good quality multimeter, you should think twice. It's not a piece of cake to get the best HVAC multimeter without proper knowledge. Certified HVAC technicians always try to pick the best tools for a perfect fault diagnosis. Of course, the most important tool is a digital multimeter. But best multimeter for HVAC technicians must possess the relevant features, like high current, temperature and capacitance measurements. You can also visit my blog of capacitance measurement.
No matter if you're an HVAC technician or just trying to improve your home HVAC system, this guide can address all your issues.
Most Common HVAC Technician's Mistakes
Several mistakes fail an HVAC system. First, most of the technicians perform the test without proper knowledge of equipment.
- First of all, if there is any fuse box, you must check that one. Unfortunately, most of the HVAC technicians forget to check the fuses.
- When it comes to air conditioning systems, people try to focus on airflow, but there is an equal chance of circuitry failure.
- Voltages are the crucial points. Always check the voltage because most of the time, over voltage and under voltage damages the system.
- Temperature sensors are the main feedback of your HVAC system. Usually, nobody focuses on thermostats or RTDs
General multimeters Vs. HVAC multimeters
A multimeter is also called a multitester. This is because it can measure almost every electrical value. The most common measuring values are resistance, capacitance, voltage, and current. But as time passes, the number of measuring values increases.
Capabilities of General Multimeters
General multimeters are the basic ones that we used to measure voltage current and resistance. Usually, these multimeters are budget-friendly and also easy to use. But unlike advanced multimeters, they lack multiple features like auto-ranging, True RMS values, and data holding options.
Capabilities of HVAC Multimeters
Unlike general purpose multimeters, HVAC multimeters can measure current more precisely. Another prominent feature is temperature sensing. The temperature reading is directly measured by just plugging the k-type thermocouple in the multimeter.
Most of the time, capacitor failure makes the HVAC system inefficient. So, advanced multimeters also help in rectifying such issues. However, in my opinion, a clamp meter is always more suitable for HVAC systems troubleshooting rather than general multimeters.
Impact of Test Leads on Multimeter
Test leads are the carriers that transfer signals to the multimeter. They're also called probes. One probe is red for live connection, and one is black for neutral/earth.
One end of the probe has a jack, and the other end is pointy for attachments. Most commonly, there are two kinds of probes used CAT-III & CAT-IV.
CAT-III test leads of the multimeter
With cat-iii probes, you can easily measure voltages up to 600 volts. In the same way, current carrying capacity is also lesser as compared to cat-iv probes. Insulation quality is good, but instantaneous short circuits may damage it.
CAT-IV test leads of the multimeter
Cat-iv test leads are specially designed to test high voltage circuits and calibrate sensitive equipment. It can measure voltages up to 1000V and current up to 20A. Most of the best fluke HVAC multimeter comes with cat-iv test leads.
When it comes to comparison, both cat-iii and cat-iv test leads are good enough. But cat-iv standard probes can carry more current and have less noise. The main distinguishing feature is the insulation, and no doubt cat-iv test leads are best among all.
Why is True RMS a must?
"True RMS value is the real-time value fluctuating value that your digital multimeter reads." Its accuracy depends upon the programming algorithm of your multimeter. In advance auto-ranging multimeters, the algorithms work to take all values and give you an average of instantaneous values.
Besides only a few advanced features, true RMS sensing meters are not different than other HVAC multimeters
Usually, if there is a malfunctioning in the control logic of HVAC electronic cards, then certified HVAC technicians calibrate the cards as per true RMS values. So, it is necessary to read the actual values instead of fluctuating ones.
Why are fluke clamp multimeters hot selling HVAC multimeter?
The easiest way to check an HVAC system's efficiency is by checking its electricity consumption. Instead of doing math or struggling with the HVAC system, just clamp the input wires and read values. Suppose the system is taking normal amperes, then it's normal. But if you're getting different results, then there must be an issue with the electrical section.
Fluke clamp multimeter for technicians is best because you don't have to touch any live wires. A C.T at the top above LCD makes it easier for you to read values.
How to measure temperature with HVAC multimeters?
If you're an HVAC technician, you don't want to carry multiple things to test here an HVAC multimeter comes in. The best thing about advanced multimeters is that they can measure temperature easily.
A k-type thermocouple comes in the kit. You just have to plug in the probes and rotate the dial on Celsius/Fahrenheit. Then, in a couple of seconds, you can read the temperature on your digital multimeter screen. Unfortunately, analog multimeters lack this feature.
Best HVAC Multimeter Kit for Professionals
A multimeter is the need of every electrician and HVAC technician. Then it's better to get a combo all in one kit. While talking about the best HVAC multimeters, then how can we ignore FLUKE.
In this regard, fluke comes with an ultimate solution, and it is FLUKE 116/323
5 Best multimeters for HVAC technicians - Reviews 2021
Finding the right multimeter for the right job needs research. To make your choices a bit easier, I have developed the best clamp multimeter for HVAC systems.
Buyer's guide for best HVAC multimeters-Review 2021
A technician is known for his skills and tools. If you're an HVAC technician without proper testing tools, then you can do nothing in time. The foremost important tool for any electrical concerned person is a digital multimeter.
Now you will think about why I am endorsing digital multimeters over analog multimeters. To know this equation to be with me. Sometimes it becomes difficult to grab the best multimeter. Here I will tell you how to grab the best multimeter for HVAC technicians.
Select your budget
Before buying anything, you must have a budget in your mind. Otherwise, you will end up buying something overrated or underrated. If you're a beginner in the field of electronics, then you can find the best multimeters under 100 dollars. But if you are an experienced HVAC technician, then do not compromise below. In my opinion, FIELDPIECE SC480 is the best multimeter for HVAC technicians.
Select your min/max ranges
The main advantage of selecting a digital multimeter instead of an analog is range. You can set your rages as per requirement. In addition, most of the advanced multimeter comes with auto-ranging functions. In an auto-ranging digital multimeter for technicians, you don't have to set ranges manually; it detects automatically.If you're looking for an auto-ranging multimeter then fluke 116 is the best multimeter for HVAC systems.
True RMS value
True RMS Values make you measure values with accuracy. A little bit of error is acceptable, but it should not exceed 0.5%. Voltage measurements need accuracy. Otherwise, you will end up with a short circuit. Normally General multimeters under a limited budget don't come with True RMS function. To make you hustle easier, I have also shortlisted 10 best budget multimeters for you.
Low impedance and low pass filters make sure to removes all noises from HVAC system circuitry. The more accurately you measure, the more it becomes easy to remove the fault from an HVAC system. In case of accuracy, I strongly recommend the KAIWEETS HT208D Digital clamp meter for an HVAC system.
A technician does not afford to open the circuits, again and again. They need something universal. In such conditions, Digital clamp meters offer the best solution. You just have to clamp the single-core live wire, and the running current will be on your display.
A clamp multimeter can do almost everything, but if you try to measure values below 10mA, it starts malfunctioning. Still, I prefer clamp multimeter over general multimeters for HVAC purposes. Because our main application is to measure current of HVAC system and loop checking.
"Safety comes first." No matter if you're a beginner or professional, safety has nothing to do with it. Always try to grab the multimeter with maximum safety features. In digital multimeters, test leads play a vital role. Good test leads save not only you but also your equipment. CAT-III or CAT-IV standard test leads are good to go.
Always must check built infuses on the input side of a multimeter. An Additional 10-ampere fuse can save you from a major explosion. Do not underestimate it.
If you're still with me, then now you might have a clear idea that what should be in a best multimeter for HVAC system. An HVAC multimeter should be compact and cheaper. Otherwise it will be difficult to carry it along the day. A little compromise on quality can be an irreversible choice. If i have to recommend you one multimeter among all then it would be Fluke 116 HVAC multimeter. So, grab the best multimeter for yourself and let us know about your experience.