Klein Tools MM600 Review – Best Auto Ranging HVAC Multimeter

Klein Tools MM600 review

Suppose someone told you to the ideal multimeter. What would you look at? Would you look at the design or material? Or would you constrain yourself to only looking at the functionality?

In our opinion, what makes a multimeter worth it is its functioning. No matter how fancy or beautiful the design might be, it all boils down to functionality. So yes, it is appealing but does it work well?

The Klein Tools MM600 is one such multimeter you would say falls on the spectrum of excellent tools. Why do we say so? Well, firstly it comes from a reputable company. Believe it or not, buyers look at a company’s reputation.

Let’s look at some of the things that rank this multimeter among the best multimeter for HVAC. Maybe you will find that it is precisely what you were looking for.

Klein Tools MM600 – Best Multimeter For HVAC

The BasicsKlein Tools MM600 HVAC Multimeter, Digital Auto-Ranging Multimeter for AC/DC Voltage, and Current, Temperature, Frequency, Continuity, More

Klein MM600 multimeter is one of the safest instruments on the market at the moment. It’s easy to say that to make it look good, but the fact it backs that up with several safety features means you can’t dismiss it wholly.

Hand in handy with the safety is how versatile it is. You can do tests of different electrical properties from current to voltage, resistance, and frequency, among others. As if that’s not enough, the multimeter also renders the need for a thermometer null.

What most people love about it, however, is the rugged build. Would you believe us if we told you that this multimeter could survive a drop from over 1 meter? To be exact, it can survive a 2-meter drop without any ramifications on its design. That tells you that this multimeter is not only hardy but also durable. You will therefore use it in demanding work environments without much of an issue. The fact anyone can use it only serves to spice it up further.

Safety RatingKlein Tools MM600 HVAC Multimeter, Digital Auto-Ranging Multimeter for AC/DC Voltage, and Current, Temperature, Frequency, Continuity, More

We have already told you that Klein MM600 is relatively safe. Well, that is thanks to the safety rating it has. The CAT III 1000V and CAT IV 600V make it one of the safest multimeter you could use.

That safety rating means you can use it for pretty much all standard voltage appliances at home and in light industrial situations. If you are an HVAC professional, you can use this multimeter in controlled electromagnetic locations without worry that it could harm you.

You, however, would be better served if you avoided certain high-voltage appliances not typical at home.

Low Input Impedance

This is an essential feature in a multimeter since it helps identify and eliminate ghost readings. It is not common in most multimeter, so we think this might be the best multimeter for HVAC.

DisplayKlein Tools MM600 HVAC Multimeter, Digital Auto-Ranging Multimeter for AC/DC Voltage, and Current, Temperature, Frequency, Continuity, More

The display is another crucial feature of a multimeter. That is where you will do the readings. It, therefore, needs to be as large and as clear as possible.

The Klein has a large display that makes it easier to read. The LCD screen has good contrast that might only waver in the sun. The display also has a backlight that ensures you can use it even in the dark.

Together with a True RMS scale, you can be sure that this multimeter will give you the most accurate results possible.

Low Battery Indicator

The low battery indicator ensures you know when the battery runs out. That means you won’t have to come back to a dead battery since you couldn’t know whether the battery is okay or not. The battery compartment is also quite accessible, and you won’t struggle to change the batteries.


The last thing a beginner wants is to have to struggle with setting a multimeter scale. It can be quite frustrating, especially if the person is new to the world of multimeters. An automatic ranging multimeter is easier to use since you don’t have to struggle setting it before using it.

Who Needs this Multimeter?

This multimeter is relatively simple in design and features, making it the ideal companion even for a beginner. Its features aren’t as complicated as with other multimeters that can test multiple electrical properties.

The fact it is affordable means anyone can access it. That, however, doesn’t measure up to the precision it affords a professional or a beginner. If you have never used a multimeter before, this one here would be a great choice.

  • Low battery indicator
  • Easy to use
  • Durable and rigid
  • Autoranging scale
  • Versatile
  • It doesn’t work that well if you are testing current over 6amps
  • The contrast might not be that good in the daytime

What We didn’t Like

This multimeter is quite good. However, there are certain things we didn’t like. For instance, you can’t use it to test current that goes well over 6amps. That defeats the purpose of buying if its functionality is limited.

Like some other multimeters, when in the sun, viewability is a problem due to changing contrast. That means you have to hold it in several angles to get an accurate and precise reading.


Is this multimeter reliable?

Yes it is a realtivey reialbel mutlimeter.

Is it an expensive multimeter?

It wouldn’t set you back over 100$, meaning it’s quite affordable.

How is the battery compartment?

It has an accessible battery compartment.

What do users Say?

The MM600 has an average rating of 4.7 stars out of 5 on Amazon. Such a rating suggests a generally likeable device. Although with a few negative reviews, most users like this multimeter and say it is dependable.

Final Thoughts

If you are looking for a multimeter for home use or other HVAC needs, you won’t go wrong choosing this one. Although it has a few features that wouldn’t impress most people, the good far outweighs the bad.

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