The 9 Best Manometers
Updated by · How we research
Gas valve and duct checks need fine, steady readings. We compared nine digital and analog manometers on range, accuracy and build; the Fieldpiece SDMN5 leads. When users buy our independently chosen editorial recommendations, we may earn commissions to help fund the Wiki.
Furnace and duct pressures are measured in inches of water column, a unit so small that one pound per square inch equals about 28 of them. A useful meter reads that scale finely, holds a steady zero and reads two ports at once. This list is for HVAC technicians, building engineers and careful homeowners checking gas and airflow.
Editor's Notes
October 27, 2026, by Ezvid Wiki Editors:
Our first choice is now the Fieldpiece SDMN5, the dual-port meter HVAC techs recommend most often. Its one-button zero, magnet and rubber boot are what service work needs. Two newcomers join it: the Klein Tools ET180, which does the same furnace and duct jobs for much less, and the UEi EM152, which ships with a calibration certificate.
We dropped the Dwyer Series 475 Mark III and the Yellow Jacket 78075 because of availability concerns. The UEi EM201B, Reed R3100, Extech HD755, RisePro HT-1890, Testo 510 and Dwyer Mark II stay.
The ranking leans on the spec sheets and manuals from Fieldpiece, Klein, UEi, Testo and Dwyer, plus a long-running heating forum thread on zero drift in hot trucks, which shaped our advice on zeroing.
Earlier notes
June 3, 2020, by Rafael Perez:
Removed the Fixkit TL-G1 because of availability issues. Added the Reed Instruments R3100 and the RisePro HT-1890.
In making our selections, we favored digital manometers over U-tube manometers. U-tube manometers like the Dwyer Mark II are extremely simple and won't break easily, however, they come with the hassle of leveling and they aren't as accurate since they depend on coarse-grained gradations on a tube whereas the pressure transducers used on models like the UEi Test Instruments EM201B and the Reed Instruments R3100 measure slight deformations produced in the internal strain gauge of the sensor (that themselves produce voltage variations) that correspond to fine-grained pressure values.
Working on pressurized vessels or heating and cooling systems is extremely dangerous and should be left to professional technicians. There are electrical hazards from the wiring systems, respiratory risks from exposure to carbon-monoxide, exposure to hazardous chemicals like refrigerant and cleaning fluids, and other forgotten hazards like falling from a ladder. DIYers will most likely be untrained at noting and circumventing dangers and so should hire a professional to make repairs and installations.
When working on heating and cooling ducts, remember to pick up some high-temperature tape in case you need to re-seal some ducts.
Special Honors
Fieldpiece SDMN6 The SDMN6 adds a built-in air pump to Fieldpiece's dual-port manometer, so a technician can test the pressure switches on furnaces and boilers by simulating draft. It reads gas pressure to about 60 inWC and static pressure in finer steps. It sells through HVAC supply houses rather than general stores. fieldpiece.com
Testo 510i Testo's 510i is a small Bluetooth differential pressure probe with no screen of its own. Readings show on a phone in the free Testo Smart Probes app, which can also save and share reports. It covers about 60 inWC either way and works with a pitot tube for air speed. testo.com
Inches Of Water, Two Ports And The Right Range
With hoses on both ports, it reads the difference, which is how you measure the drop across a filter or coil or the static pressure across a blower.
Most gas appliance and airflow work is measured in inches of water column (inWC), the height of water a pressure can hold up. It's a tiny unit: about 27.7 inWC make one psi. A manometer compares two pressures, and the classic U-tube design shows the difference as a change in fluid height. Digital meters do the same with a sensor.
Two ports matter. With one hose on the first port, the meter reads gauge pressure against the room. With hoses on both ports, it reads the difference, which is how you measure the drop across a filter or coil or the static pressure across a blower. The Fieldpiece SDMN5 and Klein Tools ET180 both read each port alone or the difference.
Pick a range that fits the job. A meter covering about 60 inWC in both directions handles furnace manifold pressure, propane appliances and duct static. Meters scaled in psi, like 2 psi budget units, show fewer useful digits on small duct readings. For air lines or pneumatics you need a much wider range, such as the 100 psi Reed R3100.
Read the media rating too. Fieldpiece rates the SDMN5 for dry, non-corrosive gases only, so it is not for refrigerant, water or corrosive gas. Never exceed a meter's overpressure limit, and leave gas valve adjustments to a licensed technician where your local code requires one.
Zero It, Watch The Temperature, Check The Calibration
Digital pressure sensors drift with temperature. A meter that spent the morning in a hot truck can read off until it settles, a pattern technicians have discussed for years on Heating Help. Let the meter reach room temperature, open both ports to the air, and press zero before every reading. Most dual-port meters have a dedicated zero button for this.
Accuracy is usually given as a percent of full scale, so a meter rated 1.5 percent on a 60 inWC scale could be off by up to about 0.9 inWC, unless the maker gives a tighter figure for low readings, as Fieldpiece does for the SDMN5. That matters on small static readings and less on gas manifold checks. The UEi EM152 manual lists a tighter 0.3 percent rating, and the meter ships with a traceable calibration certificate.
Check a meter against a known reference now and then, especially a budget model whose accuracy claim no one has verified. A simple liquid manometer makes a good cross-check because it has no electronics to drift. Technicians who need documented readings often send meters out for calibration about once a year.
When A Liquid Gauge Still Makes Sense
Liquid-column manometers predate electronics and still have a role. They need no battery, they never need zeroing beyond setting the fluid level, and they show a reading anyone can understand at a glance. An inclined tube spreads a small pressure change over a longer scale, which makes low readings easier to see. The Dwyer Mark II datasheet describes an inclined-then-vertical tube that covers 0 to 3 inWC within 3 percent of full scale.
The trade-offs are real. A liquid gauge must be mounted level, filled with the maker's fluid of the right specific gravity, and kept upright. It responds slowly, reads only a narrow range, and can't save or send readings. Readings also shift a little with fluid temperature.
That makes a liquid gauge a good permanent monitor on a filter bank, paint booth or duct, and a good reference to check a digital meter against. For service calls, a digital dual-port meter is quicker and covers far more range.
How we researched this
We compared 15 manometers, including every model from the previous version of this list, read the spec sheets, datasheets and manuals for the finalists from Fieldpiece, Klein, UEi, Testo and Dwyer, looked at owner feedback and HVAC forum discussion, and checked every brand against U.S. Consumer Product Safety Commission recall records. We found no independent lab test that compares handheld manometers.
Sources (12)
- Fieldpiece: SDMN5 dual-port manometer
- Klein Tools: ET180 digital differential manometer
- Klein Tools: ET180 datasheet
- UEi: EM152 manual
- Testo 510 data sheet (via Zoro)
- Dwyer: Mark II datasheet
- Testo: 510i smart probe
- Fieldpiece SDMN6 owner's manual (via Unilog)
- Wikipedia: Pressure measurement
- Heating Help forum: best digital manometer
- TruTech Tools: best digital manometers for HVAC techs
- U.S. CPSC recalls
Frequently asked questions
What is a manometer?
A manometer measures pressure by comparing it with a reference, often the air around it. Classic manometers use a column of liquid in a tube; digital ones use an electronic sensor and show the reading on a screen. HVAC technicians use them for gas pressure at the appliance, duct static pressure and the pressure drop across filters.
Is a digital or an analog manometer better?
For service work, a digital dual-port meter is quicker, covers a wider range and can hold or record readings. An analog liquid gauge needs no battery and doesn't drift, so it suits a permanent mount on a filter or duct and works well as a cross-check for a digital meter.
What range do I need for HVAC work?
A meter that reads about 60 inches of water column in both directions covers natural gas and propane appliance pressures and duct static pressure. Look for fine resolution at the low end, two ports and a zero button. Check the appliance's rating plate for the pressure it should run at.
Can I use a manometer on refrigerant lines?
Not a typical HVAC manometer. Fieldpiece, for example, rates the SDMN5 for dry, non-corrosive gases only. Refrigerant pressures call for refrigerant gauges or a digital manifold built for them.
How often should a manometer be calibrated?
Zero it before every reading, and compare it with a known reference now and then. Technicians who need documented readings often send meters out for calibration about once a year. Follow the maker's advice for your model.
