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At a glance
Our top picks
Fluke 116
Fluke's HVAC multimeter: a 0.1 µA flame-sensor range, temperature, capacitance and LoZ in a CAT III 600V body.
Check price on Amazon →Why we picked it ↓
Klein Tools CL445
An HVAC clamp with a 0.1 µA flame-sensor range, inrush, NCV and temperature, rated CAT IV 600V.
Check price on Amazon →Why we picked it ↓
Fluke 902 FC
A True RMS HVAC clamp with a 200 µA flame-sensor range, capacitance, temperature and Fluke Connect wireless.
Check price on Amazon →Why we picked it ↓Also great
- 4
UEi DL579Check pricePrice →Best HVAC Clamp with LoZ4.3★★★★☆ - 5
Fieldpiece SC480Check pricePrice →Best Wireless HVAC Clamp4.5★★★★★ - 6
Klein Tools MM720Check pricePrice →Best Budget Electrician's Meter4.6★★★★★ - 7
Fluke 87VCheck pricePrice →Best for Professionals4.8★★★★★ - 8
Klein Tools MM420Check pricePrice →Best Budget Klein True RMS4.5★★★★★ - 9
Fieldpiece SC260Check pricePrice →Best Compact HVAC Clamp4.2★★★★☆ - 10
Fluke 117Check pricePrice →Best Overall4.8★★★★★
Quick shopping
Compare at a glance
Swipe sideways on mobile to see every spec.
| Model | Award | Rating | Accuracy | Safety rating | Auto-ranging | |
|---|---|---|---|---|---|---|
 #1Fluke 116 | Best HVAC Multimeter | 4.6★★★★★ | True RMS | CAT III 600V | Not stated by Fluke (manual RANGE button) | Check price → |
 #2Klein Tools CL445 | Best Budget HVAC Clamp | 4.4★★★★☆ | True RMS | CAT IV 600V / CAT III 750V | Yes | Check price → |
 #3Fluke 902 FC | Best HVAC Clamp Meter | 4.5★★★★★ | True RMS | CAT III 600V / CAT IV 300V | Not stated | Check price → |
| #4UEi DL579 | Best HVAC Clamp with LoZ | 4.3★★★★☆ | True RMS | CAT IV 300V / CAT III 600V | Yes (manual RANGE) | Check price → |
| #5Fieldpiece SC480 | Best Wireless HVAC Clamp | 4.5★★★★★ | True RMS | CAT IV 600V / CAT III 1000V | Yes (manual Range button) | Check price → |
| #6Klein Tools MM720 | Best Budget Electrician's Meter | 4.6★★★★★ | True RMS, 6,000-count | CAT IV 600V / CAT III 1000V | Yes (manual RANGE button) | Check price → |
| #7Fluke 87V✓ Tested | Best for Professionals | 4.8★★★★★ | True RMS | CAT III 1000V / CAT IV 600V | Yes | Check price → |
| #8Klein Tools MM420 | Best Budget Klein True RMS | 4.5★★★★★ | True RMS, 4,000-count | CAT III 600V | Yes (manual RANGE button) | Check price → |
| #9Fieldpiece SC260 | Best Compact HVAC Clamp | 4.2★★★★☆ | True RMS | CAT III 600V | Yes (Auto Select) | Check price → |
| #10Fluke 117✓ Tested | Best Overall | 4.8★★★★★ | True RMS | CAT III 600V | Yes | Check price → |
In depth
Detailed reviews
Fluke 116
Fluke's HVAC multimeter: a 0.1 µA flame-sensor range, temperature, capacitance and LoZ in a CAT III 600V body.
Best for:HVAC flame sensors, capacitors, controls
The 116 is built around HVAC controls work. It has a 600.0 µA AC/DC range with 0.1 µA resolution for flame-rod checks, a Type K temperature input (-40 to 400 °C), capacitance to 9,999 µF for run and start capacitors, and an AUTO-V/LoZ mode that cuts ghost-voltage readings. It is True RMS with a 6,000-count backlit display and Min/Max/Average. The catch is that it has no mA or amp ranges at all, so you need a clamp meter for motor and compressor current.
Why it fits: First because it is the only meter here designed around furnace and controls work: a 600.0 µA range at 0.1 µA, capacitance to 9,999 µF, Type K temperature and LoZ in one Fluke body. Its weakness is plain: no mA or amp ranges, so motor current needs a clamp.
- Accuracy
- True RMS
- Safety rating
- CAT III 600V
- Auto-ranging
- Not stated by Fluke (manual RANGE button)
- Best for
- HVAC flame sensors, capacitors, controls
Reasons to buy
- +600.0 µA range with 0.1 µA resolution for flame sensors
- +Temperature and capacitance built in
- +AUTO-V/LoZ against ghost voltages
Reasons to avoid
- −No mA or amp ranges, so current needs a separate clamp
- −CAT III 600V only
Klein Tools CL445
An HVAC clamp with a 0.1 µA flame-sensor range, inrush, NCV and temperature, rated CAT IV 600V.
Best for:HVAC techs: amps, inrush, flame sensors
The CL445 is Klein's HVAC clamp. It measures AC current to 600 A with an inrush mode, and through the test leads it reads DC microamps (600.0 µA, 0.1 µA resolution) for flame sensors, capacitance to 6 mF and temperature from -148 to 1832 °F. It shows volts and amps at the same time, has NCV in the jaw, a backlit 6,000-count display and a worklight. AC voltage stops at 750 V, DC at 600 V, and it can't clamp DC current.
Why it fits: Second because a single clamp handles amps, inrush, flame-sensor microamps through the leads, capacitance to 6 mF and temperature, with NCV in the jaw and a CAT IV 600V rating. Klein lists no LoZ mode, and the jaw reads AC current only.
- Accuracy
- True RMS
- Safety rating
- CAT IV 600V / CAT III 750V
- Auto-ranging
- Yes
- Best for
- HVAC techs: amps, inrush, flame sensors
Reasons to buy
- +DC µA range with 0.1 µA resolution
- +Inrush mode and simultaneous V + A display
- +NCV, backlight and worklight
Reasons to avoid
- −No DC amps through the clamp
- −No LoZ mode listed
Fluke 902 FC
A True RMS HVAC clamp with a 200 µA flame-sensor range, capacitance, temperature and Fluke Connect wireless.
Best for:HVAC service: amps, flame sensors, capacitors
The 902 FC combines a 600 A AC clamp with a DC µA range (200 µA, 0.1 µA resolution) for flame rectification, capacitance to 1,000 µF, contact temperature and Min/Max recording. Readings can be sent to a phone with Fluke Connect. Its CAT III 600V / CAT IV 300V rating and 600 V limit suit residential and light-commercial equipment. Fluke doesn't list a LoZ mode, DC amps or inrush, and resistance stops at 60 kΩ.
Why it fits: A Fluke HVAC clamp with a 200 µA DC range, capacitance to 1,000 µF, temperature, Min/Max and Fluke Connect for sending readings to a phone. It ranks behind the CL445 because Fluke lists no inrush or LoZ, resistance stops at 60 kΩ and its CAT IV rating is only 300V.
- Accuracy
- True RMS
- Safety rating
- CAT III 600V / CAT IV 300V
- Auto-ranging
- Not stated
- Best for
- HVAC service: amps, flame sensors, capacitors
Reasons to buy
- +DC µA range (200 µA, 0.1 µA) for flame sensors
- +Capacitance to 1,000 µF and temperature
- +Fluke Connect wireless logging
Reasons to avoid
- −No DC amps, inrush or LoZ listed
- −Resistance only to 60 kΩ
UEi DL579
An HVAC/R clamp with AC/DC microamps, Low Z, LRA inrush and two temperature probes.
Best for:HVAC/R techs who want µA, Low Z and inrush
The DL579 targets HVAC/R troubleshooting. It clamps AC current to 600 A, reads AC and DC microamps (600.0 µA at 0.1 µA, up to 2,000 µA) for flame sensors, and has Low Z, NCV and LRA inrush. Capacitance runs to 6,000 µF, temperature from -328 to 2462 °F, and the kit includes two K-type probes. It has a backlit dual display, auto and manual ranging, and reads 1000 V DC / 750 V AC. Its CAT IV 300V / CAT III 600V rating is lower than some rivals, the warranty is one year, and the clamp doesn't read DC amps.
Why it fits: It has the widest HVAC function list of the clamps: AC and DC microamps, LoZ, NCV, LRA inrush and two K-type probes in the kit for split temperatures. Its CAT IV 300V / CAT III 600V rating and one-year warranty keep it below the two clamps above.
- Accuracy
- True RMS
- Safety rating
- CAT IV 300V / CAT III 600V
- Auto-ranging
- Yes (manual RANGE)
- Best for
- HVAC/R techs who want µA, Low Z and inrush
Reasons to buy
- +AC/DC µA ranges with 0.1 µA resolution
- +Low Z, NCV and LRA inrush
- +Two K-type temperature probes included
Reasons to avoid
- −No DC amps through the clamp
- −CAT IV only to 300V; one-year warranty
Fieldpiece SC480
An HVACR power clamp that measures watts and power factor, checks phase rotation and sends readings to the Job Link app.
Best for:HVACR techs who need power, phase rotation and app logging
The SC480 does more than a standard HVAC clamp. Besides 600 A AC, inrush, a 1000 µA DC range (0.1 µA) for flame sensors, capacitance to 10 mF and temperature from -58 to 2372 °F, it measures active power (W), VA, VAr and power factor, checks 3-phase rotation, and has a low-pass filter for VFD voltage. Readings go to the Job Link app over Bluetooth. It is CAT IV 600V / CAT III 1000V with a 10,000-count dual display, but it can't clamp DC current and the warranty is one year.
Why it fits: The pick for commercial techs: besides a 1000 µA DC range, inrush, capacitance to 10 mF and temperature, it reads watts, power factor and phase rotation and filters VFD output voltage. That depth costs a lot more than the CL445, and the jaw reads AC current only.
- Accuracy
- True RMS
- Safety rating
- CAT IV 600V / CAT III 1000V
- Auto-ranging
- Yes (manual Range button)
- Best for
- HVACR techs who need power, phase rotation and app logging
Reasons to buy
- +Watts, VA, VAr and power factor
- +Phase rotation, inrush and VFD low-pass filter
- +µA DC range and Job Link wireless
Reasons to avoid
- −No DC amps through the clamp
- −One-year warranty
Klein Tools MM720
CAT IV 600V, 1000V, LoZ and True RMS at a budget price, the most panel-ready meter in this tier.
Best for:Electricians working panels and feeders
The MM720 is rated CAT IV 600V / CAT III 1000V and measures up to 1000V AC/DC, with a LoZ mode for ghost voltages. It is True RMS, auto-ranging and 6,000-count, and the reverse-contrast display adjusts itself to the light. Current runs from a 600.0 µA range (0.1 µA) to 10 A. It adds 60 MΩ resistance, capacitance to 6,000 µF, temperature to 1832°F, IP42 and a 2 m drop rating, and a carrying pouch comes in the box. Klein lists no NCV.
Why it fits: The strongest lead-type meter here for residential HVAC after the 116: 0.1 µA resolution, capacitance to 6,000 µF, a thermocouple in the box, LoZ and CAT IV 600V, at a much lower price than the Fluke 116. It has no clamp, so pair it with one for running amps.
- Accuracy
- True RMS, 6,000-count
- Safety rating
- CAT IV 600V / CAT III 1000V
- Auto-ranging
- Yes (manual RANGE button)
- Best for
- Electricians working panels and feeders
Reasons to buy
- +CAT IV 600V and 1000V AC/DC
- +LoZ mode for ghost voltages
- +IP42, 2 m drop rating and pouch included
Reasons to avoid
- −Priced at the top of the budget tier
- −No non-contact voltage detection
Fluke 87V
The step-up pick for anyone who needs CAT IV protection and high-resolution readings daily.
Best for:Industrial technicians, daily professional use
The 87V is Fluke's industrial-grade step up from the 117 — a 1000V CAT III / 600V CAT IV rating, a 6,000-count main display with a 19,999-count high-resolution mode, and a 32-segment analog bar graph for watching signals change in real time.
Why it fits: It carries our Hands-on Tested badge and has everything a flame-rod and capacitor check needs, plus CAT IV 600V and a 1000 V range for industrial jobs. It sits mid-table because Fluke lists no LoZ mode and it costs far more than meters that cover HVAC as well.
- Accuracy
- True RMS
- Safety rating
- CAT III 1000V / CAT IV 600V
- Auto-ranging
- Yes
- Best for
- Industrial technicians, daily professional use
Reasons to buy
- +Joint-highest CAT rating in this list (CAT IV 600V / CAT III 1000V)
- +19,999-count high-resolution mode
- +Analog bar graph tracks fast-changing signals
Reasons to avoid
- −Among the most expensive picks here
- −Overkill for casual home use
Klein Tools MM420
Klein's everyday True RMS, auto-ranging meter: µA to 10 A, temperature and capacitance, rated CAT III 600V.
Best for:Home electrical, HVAC and appliance work
The MM420 is a 4,000-count, True RMS, auto-ranging meter rated CAT III 600V. It measures AC/DC current from a 400.0 µA range (0.1 µA resolution) up to 10 A, resistance to 50 MΩ, capacitance to 400 µF, frequency to 50 kHz and temperature from -40 to 1832°F with the included thermocouple. Lead-Alert lights show which jacks to use, it has Min/Max, a backlight and a 2 m drop rating. There's no LoZ mode or NCV, and Klein rates it for indoor use only.
Why it fits: A sensible apprentice meter: True RMS with a 400.0 µA range, a thermocouple and capacitance to 400 µF, which covers typical run capacitors. Klein rates it for indoor use and CAT III 600V, and it has no LoZ, so it ranks behind the MM720.
- Accuracy
- True RMS, 4,000-count
- Safety rating
- CAT III 600V
- Auto-ranging
- Yes (manual RANGE button)
- Best for
- Home electrical, HVAC and appliance work
Reasons to buy
- +µA, mA and 10 A ranges on AC and DC
- +Temperature, capacitance and frequency included
- +Lead-Alert jack lights help beginners
Reasons to avoid
- −No LoZ mode or non-contact voltage detection
- −CAT III 600V only, not for service-entrance work
Fieldpiece SC260
A small True RMS HVACR clamp with capacitance, temperature and NCV, but no microamp range.
Best for:A compact backup clamp for AC/R service
The SC260 is Fieldpiece's pocket-sized HVACR clamp: 400 A AC, 600 V AC/DC, capacitance from 4 nF to 4 mF for run caps, Type K temperature from -30 to 752 °F, NCV and a blue backlight, with a swivel magnet for hanging. Auto Select picks the measurement from what the leads detect. Fieldpiece's manual lists no microamp range, so it can't check flame sensors, and it has a 4,000-count display and a one-year warranty.
Why it fits: A compact clamp with capacitance to 4 mF, temperature, NCV and a swivel magnet, handy as a second tool in the van. It ranks low because Fieldpiece lists no microamp range, so it cannot check a flame sensor.
- Accuracy
- True RMS
- Safety rating
- CAT III 600V
- Auto-ranging
- Yes (Auto Select)
- Best for
- A compact backup clamp for AC/R service
Reasons to buy
- +Capacitance to 4 mF for run and start caps
- +Temperature and NCV built in
- +Small, with a swivel magnet
Reasons to avoid
- −No microamp range for flame sensors
- −4,000-count display and one-year warranty
Fluke 117
The meter working electricians actually buy with their own money, not just the one brands push.
Best for:Electricians, serious hobbyists
The Fluke 117 is the meter most working electricians reach for. True RMS readings, non-contact voltage detection, and a CAT III 600V rating make it reliable in real electrical panels, not just hobby projects.
Why it fits: It carries our Hands-on Tested badge, and its LoZ mode, NCV and capacitance make it good at control-circuit voltage checks. For HVAC it ranks last because it has no microamp range and no temperature input, and its lowest current range starts at amps.
- Accuracy
- True RMS
- Safety rating
- CAT III 600V
- Auto-ranging
- Yes
- Best for
- Electricians, serious hobbyists
Reasons to buy
- +Trusted, well-documented reliability
- +Non-contact voltage (NCV) detection built in
- +Durable enough for daily field use
Reasons to avoid
- −Premium price for casual hobbyists
- −No Bluetooth/app connectivity
Before you buy
Buying advice
Decide whether your first tool is a clamp or a lead meter
A modern HVAC clamp now carries most of a multimeter's jobs, so for a tech who buys one instrument the Klein CL445, Fluke 902 FC or UEi DL579 covers more service calls than a lead-only meter. A dedicated lead meter such as the Fluke 116 or Klein MM720 still wins on LoZ, resolution and a comfortable probe grip for board-level control work. Many techs end up with one of each.
Check the microamp range before anything else
No-heat calls with a furnace that lights and then shuts down are often a dirty or failing flame rod. Reading flame current needs a DC µA range in series with the sensor wire. Four of the meters people often shortlist for HVAC, the Fluke 115, Fluke 117, Fieldpiece SC260 and Milwaukee 2235-20, list no microamp range, so read the dial and spec sheet before you buy.
Match the capacitance range to the parts you test
Residential run capacitors are single-digit to tens of microfarads, which even the MM420's 400 µF range covers. Start capacitors run into the hundreds of microfarads, and a 1,000 µF ceiling is tight for big ones. Meters reading several thousand µF, like the Fluke 116, Klein CL445 and Fieldpiece SC480, leave headroom for any capacitor you will meet.
Look past the clamp's current rating
Every clamp here reads at least 400 A AC, far above a residential compressor's running current. The useful differences are inrush capture for locked-rotor and hard-start diagnosis, a CAT IV rating if you work near service equipment, and extras such as watts and phase rotation on the SC480 for three-phase rooftop units.
Methodology
How we chose
We ranked these ten for HVAC service and troubleshooting: first by how many core tests each covers on its own (flame-sensor microamps, capacitance, temperature, clamp current and inrush), then by LoZ, CAT rating and extras such as power and phase rotation. Every figure comes from the maker's site, datasheet or manual; the ranking is desk research, and only the Fluke 87V and Fluke 117 carry our Hands-on Tested badge.
Picks marked "Hands-on Tested" have been bought and tested by us; the rest are desk research. A pick only carries that badge once we have actually bought and tested that unit. More on how we research.
Questions
Frequently asked questions
What features does an HVAC multimeter need?+
Look for a DC microamp range for flame sensors, capacitance for run and start capacitors, a Type K temperature input, and a low-impedance (LoZ) voltage mode for control wiring. Add True RMS for variable-speed motors and at least a CAT III 600V rating. If the meter has no clamp, you will also need a clamp meter to read motor current.
Can any multimeter test a furnace flame sensor?+
No. Flame sensor current is measured in microamps, so the meter needs a DC µA range, ideally with 0.1 µA resolution. The Fluke 117, Fluke 115 and Fieldpiece SC260 have no microamp range, while every other meter here does. You put the meter in series with the flame rod wire while the burner runs and compare the reading with the furnace maker's minimum.
Should an HVAC tech buy a clamp meter or a multimeter?+
Many techs carry both, but an HVAC clamp such as the Klein CL445, Fluke 902 FC or UEi DL579 now covers microamps, capacitance and temperature as well as clamp current. A lead-type meter like the Fluke 116 adds finer resolution and LoZ but cannot read motor amps. If you buy one tool first, an HVAC clamp with a µA range covers more calls.
How do you test a run capacitor with a multimeter?+
Kill power, then discharge the capacitor safely before touching its terminals. Disconnect the wires, set the meter to capacitance and connect the leads across the terminals (for a dual capacitor, test C to HERM and C to FAN separately). Compare the reading with the microfarad rating and tolerance printed on the can; a reading below tolerance means replacement.
Why does LoZ mode matter on HVAC controls?+
Long thermostat and control cable runs often sit beside powered conductors, so a high-impedance meter can show a voltage that is only capacitive coupling. LoZ mode puts a low-impedance load across the leads, so ghost voltage collapses and a real supply stays. The Fluke 116, Fluke 117, Klein MM720 and UEi DL579 have LoZ.
Is CAT III 600V enough for HVAC work?+
For most residential and light-commercial equipment, yes: condensers, air handlers and their disconnects are downstream of the panel, which is CAT III territory, and supply voltages stay below 600 V. If you also work on service entrances or outdoor feeders, choose a CAT IV 600V meter such as the Klein MM720, Fluke 87V, Klein CL445 or Fieldpiece SC480.
