Built for tradies: Viper Big Blu SubZero (1L) is a freeze-resistant, NSF-certified bubble leak detector that finds micro leaks fast on any gas line — even in cold rooms and on hot discharge lines. Ideal for HVAC/R techs, apprentices and contractors who want fewer call-backs and quicker fault isolation. Fair dinkum, it just works.
It forms a strong, persistent film so leaks show up as tight bubbles or white foam “cocoons”. You’ll spot tiny leaks others miss, then get off site quicker. No dramas.
Key Features & Trade Benefits
- Freeze-resistant to −34 °C — bubbles keep forming where other fluids freeze or turn gelatinous; ideal for freezer rooms and winter jobs.
- Detects micro leaks down to ~22.4 g/yr (0.79 oz/yr) — nail tiny leaks fast and reduce costly call-backs.
- NSF certified & non-corrosive — safe in food service areas; gentle on metals, plastics and rubber, so components last.
- All-gas compatible (incl. oxygen) — one bottle for mixed sites; standardise your leak-check process.
- Wide temp window (≈ −34 °C to +95 °C) — stays fluid on frosty lines and resists evaporation on hot discharge.
- High-visibility bubble action — film-forming action makes pinhole leaks obvious; quicker diagnosis = faster sign-off.
- 1 L spray bottle — job-ready format for service vans and site work.
Why This Product Matters
Trade yarn: busy bottle-shop in Perth — freezer merchandiser losing temperature by midday. We hit every flare, braze and valve with SubZero, and a cluster of tiny bubbles showed up on a frosted elbow we’d have missed with standard soap. Quick clean-up, re-braze, pressure test and back to setpoint before smoko. She’ll be right when you can see the micro stuff.
Stock up on more leak-finding gear in our Leak Detectors category for electronic sniffers and accessories.
Pro Tip
Spray a flat, bubble-free film and give suspected joints 5–30 minutes — micro leaks often appear as white foam cocoons. Purge with nitrogen while brazing, then repeat the check after the system is back under operating vibration. You’ll cut return visits.
Compatibility & System Info
- Gases: All common HVAC/R refrigerants (HFCs, HFOs, HCFCs), hydrocarbons (R290/R600a), CO, air, oxygen and more.
- Temperature range: approx. −34 °C to +95 °C.
- Use cases: HVAC/R lines, gas lines, brake/pneumatic circuits, EV refrigerant thermal loops, fire suppression, hydraulics.
Local note: In Sydney humidity and Brisbane heat, SubZero resists evaporation on hot discharge lines. In Melbourne winters and cold rooms, it stays fluid so bubbles keep forming — bloody good for finding hairline leaks.
What’s Included
- Viper Big Blu SubZero 1 L spray bottle
- Usage directions on label (quick reference)
Specifications
| Item | Spec |
|---|---|
| Brand / Model | Refrigeration Technologies — Big Blu SubZero (RT150S) |
| Bottle size | 1 L spray |
| Detection sensitivity | ≈ 22.4 g/year (0.79 oz/year) |
| Temperature range | ≈ −34 °C to +95 °C (−30 °F to 200 °F) |
| Certification | NSF certified for use around food |
| Material compatibility | Non-corrosive to metals, plastics, rubber |
| Gas compatibility | Safe on any type of gas (incl. oxygen) |
| Formulation | Film-forming bubble/foam indicator |
Warranty & Returns
Backed by store support. See our Shipping & Returns policy for change-of-mind, transit damage and warranty information.
FAQs
SubZero is engineered for extreme cold — it stays fluid down to around −34 °C and keeps forming bubbles. Standard Big Blu is great for general work but isn’t built for sub-zero environments.
Yes — SubZero is NSF certified for food areas and is oxygen-safe. Still wipe or rinse after testing where practical.
No — the formulation is non-corrosive to metals, plastics and rubber. It’s designed for regular trade use.
Yep — if you’re burning through bottles, grab the Big Blu SubZero 3.78 L for the workshop.
Related Products
- Fieldpiece DR82 Infrared Leak Detector — pinpoint leaks faster; great partner to soap testing.
- Testo 316-3 Leak Detector — sensitive heated-diode sniffer for small refrigerant leaks.
- Viper Big Blu Brush-On — handy dauber for overhead or awkward joints.
- Bradley NR1000 Nitrogen Regulator — stable pressure testing before you soap.
Working with refrigerants in Australia? Check the Australian Government guidance for RAC technician licensing and leak-handling obligations.