Review of the Best Digital Multimeters for HVAC and DIYers in 2014: Fluke, Fieldpiece, and Extech

Reviewed here are some of the best digital multimeters (DMM) for 2014, including multimeters by Fluke, Fieldpiece, and Extech. Digital multimeters come with a range of different features whether you are a professional or student working in heating, ventilation, and air conditioning (HVAC) or a hobbyist or interested in do-it-yourself (DIY) projects looking for a quality multimeter rather than a cheap alternative. Reviewed here are true RMS (root-mean-squared) multimeters, unlike more affordable "average responding meters", true RMS (TRMS) meters are more accurate at taking voltage and current readings. Quoting the Stedi-Power website, average responding meters produce correct readings on linear loads such as standard induction motors, resistance heating, and incandescent lights. But when loads are non-linear, those containing semiconductors, the average responding meters typically read low. You can find more information on the benefits of true RMS meters on the Stedi-Power website. If a multimeter does not describe itself as a true RMS meter, you are probably dealing with a averaging responding meter.

Fluke 115 Compact True-RMS Digital Multimeter

We compare two Fluke multimeters, the Fluke 115 versus the Fluke 116; often it is hard to get a good recommendation and figure out which meter is best. The Fluke 115 is a solid quality and robust True RMS (TRMS) meter making it one of the best all-around multimeters for the money and worth the extra price. It comes with a crisp display, a rubberized outer case, and stand and has the common buttons to hold the display, show min/max, and display a range; the meter comes with also comes with a black light. The meter comes with three inputs: 1: common, 2: voltage resistance, continuity, capacitance, and diode, and 3: current. Fluke meters make ideal automotive multimeters for diagnosing electrical circuits in cars. One major con to this meter compared to the others reviewed here is the absence of a milliamp or microamp reading feature.

Fluke 116 HVAC Multimeter with Temperature and Microamps

The Fluke 116 is similar to the Fluke 115, but it includes two big features that are missing in the Fluke 115, temperature and microamp detection features that make it a suitable multimeter for HVAC technicians. Also, unlike the Fluke 115, the Fluke 116 has automatic voltage (Auto-V) detection to automatically detect whether a voltage is AC or DC and display the correct information. The Fluke 115 is also missing the Low Impedence (Z, LoZ) feature that uses a low impedance input to reduce false readings due to ghost voltages and improve accuracy when detecting the presence of voltage.

Fieldpiece HS36 Expandable Autoranging True RMS Stick Multimeter w/Backlight

The Fieldpiece HS36 is one of the most commonly used multimeters by HVAC service technicians. This meter does not provide a rubberized holster, but does provide grips around the sides and includes a backlight and min/max functionality. This meter can test voltage, continuity, and capacitance. Like the Fluke 116, it can also test temperature using the included probe. Fieldpiece also sells an a pipe clamping accessory to measure the temperature of pipes. This meter possesses a non-contact voltage (NCV) detection feature that can detect changes in electric fields around AC energized objects without the need for direct metallic contact. This is an important safety feature anyone, especially maintenance workers, coming in contact with energized electrical components; more information can be found here on this page describing NCV testers.. Fluke meters, such as the Fluke 117, have this non-contact voltage detection feature with the name VoltAlert; versus the Fluke 115 or Fluke 116 neither have this feature. The Fieldpiece HS36 also comes with a wire clamping amp probe; unlike the Fluke 115, the Fieldpiece HS36 can measure microamps. This meter has a high price, but if you an HVAC professional or student, then this is one of the best multimeters for the money and may cost you less than Fluke multimeters in the long run, since you won't have to spend additional money on other tools.

Extech EX430 True RMS Autoranging Multimeter with K Type, Capacitance, Frequency, and Duty Cycle

The Extech 430 is also a True RMS (TRMS) multimeter and the cheapest one reviewed here. It includes a large, high contrast display with a backlight. Compared to the Fluke 115, the Extech 430 also includes a rubber holster and a tilt stand; the tilt stand can also be used to suspend the multimeter using a velcro strap. This multimeter warns using a visual and auditory warning if the input leads do not match the selected measuring function. Included with this model is a Type K adapter to measure temperature, useful for HVAC testing of heaters and air conditioners temperatures. The Extech 430 can measure frequency of electronic circuits (up to 10 Mhz), capacitance (useful for testing motor-starting capacitors), and duty cycle, which cheaper models of the Extech 400 series cannot. The more advanced Extech 470 model has a built-in laser thermometer. The Extech EX430 is one of the best budget multimeters reviewed here and it is great for house and automotive electrical troubleshooting.