Hydrogen and helium leak detection , built for the field.
H2Leak equips technicians across the USA with trace-gas hydrogen leak detectors and helium leak detectors — for water lines, HVAC systems, and refrigeration equipment.
Four instruments, four service calls
04 UNITSEvery leak detection job has a different failure mode — a hairline crack in a buried copper line, a slow refrigerant bleed on a rooftop condenser, a fitting on a supermarket refrigeration rack that's lost a few ounces of gas over a year. Hydrogen leak detection and helium leak detector technology solve these differently than a basic combustible-gas sniffer, which is why each instrument in this lineup is purpose-built for one application rather than compromising across all of them.
Below is the full H2Leak lineup, with the service application each unit is built for. Techs can jump straight to the unit that matches their trade, or scroll the comparison table further down to weigh detection method, gas type, and typical use case side by side.
Locating leaks in buried and slab water lines without excavation guesswork. The Hydro-Lok™ pairs a 5% H₂ / 95% N₂ tracer gas mix with a field-replaceable flex-hose probe, so a technician can walk the suspected pipe run and read the gas rising through soil, gravel, asphalt, or concrete straight to the surface — no digging test pits along the way.
Download Hydro-Lok™ Datasheet (PDF)- 5% H₂ / 95% N₂ tracer gas
- Flexible sniffer probe
- 3-level sensitivity dial
- USB-C · ~12 hr battery
Residential water services
Main service lines, yard leaks, slab leaks, irrigation systems, and pool plumbing.
Municipal water systems
Distribution mains, service connections, and pressure-testing verification on new water mains.
Commercial & industrial
Process and cooling water piping at hotels, hospitals, schools, and manufacturing facilities.
Daily hydrogen leak detection work on automotive A/C, EV heat-pump, and residential/commercial HVAC systems. The DXH-240 reads a non-flammable 5% H₂ / 95% N₂ mix at ppm-level sensitivity with sub-1-second response, catching micro-leaks that refrigerant sniffers and UV dye often miss.
Download DXH-240 Datasheet (PDF)- 5% H₂ / 95% N₂ tracer gas
- Flexible sniffer probe
- <1 sec response time
- USB-C · 12 hr battery
New install pressure testing
Charge with tracer and sweep brazed joints and flare fittings before final refrigerant charge.
Coil & evaporator checks
Screen indoor and outdoor coils for pinhole leaks during routine maintenance visits.
Automotive A/C service
Pressurize with tracer and sweep evaporators, hoses, O-rings, and compressor housings.
Dual-method leak detection for HVAC and refrigeration technicians — one handheld unit that switches between refrigerant-gas (HFC, HFO, HC) sensing and H₂/N₂ tracer detection, depending on what's already charged in the system. Sensitivity down to roughly 1 g/year refrigerant equivalent catches micro-leaks other sniffers miss.
Download DXR-240 Datasheet (PDF)- Refrigerant sensor: HFC/HFO/HC
- Tracer sensor: H₂/N₂
- ~1 g/yr min. sensitivity
- USB-C · 8 hr battery
Commercial refrigeration racks
Sweep manifolds, valves, and case evaporators on supermarket and cold-storage systems.
EPA & GreenChill compliance
Support leak-rate inspection and reduction programs on systems above regulatory thresholds.
VRF systems & chillers
Commission new piping and diagnose slow refrigerant loss on VRF, chiller, and rooftop units.
Industrial multi-gas leak detection using thermal-conductivity (catharometer) sensing — a single instrument that detects helium, argon, hydrogen, CO₂, SF₆, oxygen, and nitrogen. Built for tightness testing, maintenance, and expert diagnostics across HVAC/R systems, vacuum systems, and industrial process equipment.
Download TG Expert Datasheet (PDF)- Thermal conductivity (catharometer)
- He, Ar, H₂, CO₂, SF₆, O₂, N₂
- He: 1×10⁻⁵ cc/s · Ar: 5×10⁻⁵ cc/s
- High / medium / low sensitivity
Pressure vessel & process testing
Verify weld and fitting integrity on pressure vessels and industrial process piping.
Vacuum & scientific systems
Screen vacuum chambers, research equipment, and semiconductor cleanroom systems for micro-leaks.
Gas pipeline & storage
Locate leaks on pipelines and gas storage systems using helium or hydrogen tracer.
Side by side
Match the tracer gas and detection method to the job before it's on the truck. A quick reference across all four units.
| Unit | Service application | Tracer / detection type | Format |
|---|---|---|---|
| Hydro-Lok™ | Underground water line leak detection | 5% H₂/N₂ tracer, flex probe | Handheld probe |
| DXH-240 | HVAC & automotive A/C servicing | 5% H₂/N₂ tracer, ppm-level | Handheld |
| DXR-240 | Refrigerant & hydrogen leak detection | Dual sensor: HFC/HFO/HC + H₂/N₂ | Handheld |
| TG-Expert | Precision multi-gas leak detection | Thermal conductivity, He/Ar/H₂/CO₂/SF₆ | Handheld |
Why tracer gas over soap and sound
METHODSmall molecule, fast escape
Hydrogen is the smallest molecule available as a tracer, so it finds its way through leak paths that other test methods miss entirely. Mixed at 5% in nitrogen, it's non-flammable to handle on the job, and a hydrogen leak detector reads it at concentrations far below what a soap-bubble test or UV dye can catch — useful on buried lines and brazed joints where the leak itself may be invisible.
Inert, precise, lab-grade
Helium is chemically inert and diffuses quickly, which is exactly what's needed on sealed systems and cryogenic equipment where any reactive tracer would be a liability. A helium leak detector like the TG-Expert is built to catch the smaller leak rates that matter in these settings, where a slow loss adds up over months rather than showing up as an obvious failure.
| Property | 5% H₂ / 95% N₂ Tracer Mix | 100% Helium |
|---|---|---|
| Background level in air | ~0.05 ppm — very low noise floor | ~0.5 ppm — 10× higher background |
| Combustibility | Non-combustible below 5.7% H₂ in N₂ — green-label safe at 5% | Not combustible (inert), but supply is a pressurized gas hazard like any compressed cylinder |
| Diffusion behavior | Small molecule, rises quickly through soil, asphalt, and concrete | Very light, fast-diffusing, inert — ideal in sealed/vacuum systems |
| Typical cost | Roughly 15–25% the cost of 100% helium | Higher and rising — helium supply is limited and price-volatile |
| Best suited for | Underground pipe, HVAC/automotive A/C, refrigerant systems — high-volume field service work | Vacuum systems, sealed vessels, and lab/industrial work where inert gas is required |
In practice, cost is usually the deciding factor when a shop moves from helium to a hydrogen tracer gas mixture. The 5% H₂ / 95% N₂ mix runs roughly 15–25% the cost of 100% helium, and unlike helium — which is in limited supply and has grown steadily more expensive — hydrogen supply is stable and inexpensive to refill. Lowering the helium percentage in a mix doesn't fix this either: it reduces detector sensitivity to small leaks, and factory gas-blending adds its own cost, so the savings rarely justify the trade-off.
Frequently Asked Questions
FAQIsn't hydrogen dangerous and explosive?
In 100% concentration, that is the case. We always recommend using 5% hydrogen mixed with 95% nitrogen because hydrogen is not combustible in nitrogen until hydrogen represents 5.7%. This mixture is green label non-combustible, therefore it will never have the ability to combust or increase the intensity of a fire.
Will the hydrogen in the mixture settle out and cause an unsafe condition?
No, it remains mixed at all times. Inert gases cannot stratify. If they did, the gas that makes up our atmosphere would stratify into pockets of disparate gases resulting in all of our deaths.
Which is better as a tracer gas, hydrogen or helium?
In the past, helium was the best tracer gas because of its availability, the reliability of equipment to detect it, and its low background amount in air (0.5 ppm). Using hydrogen mixture as a tracer gas has become more popular because instruments like the TLD.500 and TLD.1000 have drastically improved in being able to find small leaks. Also, helium is in short supply and expensive. Another benefit is that hydrogen also has a low background in air (0.05 ppm).
What is the cost of the 5% hydrogen, 95% nitrogen tracer gas compared to helium?
5% H₂ / 95% N₂ is 15–25% the cost of 100% helium. While there are efforts to lower the helium concentration to also lower the cost, that affects the sensitivity of the helium leak detector to find smaller leaks. Also, because the helium/nitrogen is now a mixed gas, there is a charge to mix it at the factory. Therefore, cost savings by lessening helium amounts in the mixture may not significantly reduce overall cost.
Where have hydrogen leak detectors been used in the past?
Hydrogen leak detectors were used extensively in locating leaks during the telecom boom of the late 1990s. Since then, hydrogen leak detectors have improved, leading them to be used in applications where lower detection of leak rates is required. In the future, hydrogen leak detectors will be used for detecting and locating leaks in underground water lines or pipes. Water has increasingly become a strategic resource and leak detection is getting more important. Our TLD.500 starts in price at $998, allowing more plumbers and leak detection companies to be able to employ tracer gas leak detection into their portfolio of capabilities.
For more information on our leak detection equipment, applications, and services, visit us online or reach out to our sales department.
www.h2leak.com