Protimeter HygroMaster 2 Kit with Hygrostick, Surface Probe and Case
The Protimeter HygroMaster 2 is a professional handheld thermo-hygrometer. It measures relative humidity, air temperature, dew point and specific humidity, reads surface temperature by infrared or contact probe, and shows how close a surface is to dew point. It also logs unattended at intervals from one minute to 24 hours and downloads to PC software.
This kit adds a plug-in surface temperature probe to the instrument, which is what you need to compare surface temperature against dew point reliably on glass, gloss paint, polished tile and other low-emissivity surfaces where the infrared reading is less dependable. It ships with the Hygrostick, the sensor for sustained high humidity and equilibrium relative humidity in concrete.
What is in the box
- HygroMaster 2 instrument
- Hygrostick humidity sensor (POL4750)
- Surface temperature probe
- USB cable and PC logging software
- Compact soft touch case and wrist strap
- Instructions
- 1 × 9 V battery
Important — BLD7752 and BLD7753 differ only by the sensor
These two part numbers are the same instrument, the same surface temperature probe and the same case, at the same price. The only difference is which humidity sensor is in the box: BLD7752 ships the Quickstick ST (0–99% RH), BLD7753 ships the Hygrostick (30–98% RH). Confirm which you need before ordering — the wrong one cannot be made to read the range you want.
The HygroMaster 2 range
Every version below contains the same instrument. The difference is the sensor and what else is packed with it.
| Part number | Sensor supplied | Also includes |
|---|---|---|
| BLD7750 | Hygrostick | — |
| BLD7751 | Quickstick ST | — |
| BLD7752 | Quickstick ST | Surface temperature probe |
| BLD7753 | Hygrostick | Surface temperature probe |
| BLD7758H | Hygrostick | Extension lead and humidity sleeves for flooring |
| BLD7759 | Hygrostick | Extension lead and humidity box |
Hygrostick or Quickstick — the choice that matters
The HygroMaster 2 takes two interchangeable humidity sensors. They are not equivalent, and picking the wrong one is the single most common mistake on this instrument.
| Hygrostick (POL4750) | Short Quickstick (POL8751) | |
|---|---|---|
| Humidity range | 30% to 98% RH | 0% to 99% RH |
| Below 30% RH | Will not read | Reads to 0% |
| Best for | Sustained high humidity, equilibrium RH in concrete, harsh environments | General ambient work, fast spot readings, drying verification |
| Response | Slower, stable under prolonged wet conditions | Fast — nominally 30% to 90% and back in about 45 seconds |
The practical consequence: if you are documenting a structure that has finished drying, ambient readings often sit below 30% RH and a Hygrostick simply will not report them. If you are leaving a sensor in a sleeved hole in a slab for hours, the Hygrostick is the sensor built for it.
Both are replaceable and both are consumables — they drift with age and exposure. Buy Hygrosticks singly or in a 5 pack, and Quickstick ST sensors singly.
Specifications
Taken from the HygroMaster 2 instruction manual, INS7750 Rev B.
| Measures | Relative humidity, air temperature, dew point, specific humidity (mixing ratio, g/kg or GPP), surface temperature and surface proximity to dew point |
|---|---|
| Hygrostick (POL4750) | 30–40% RH ±3% at 20°C; 41–98% RH ±2% at 20°C. Temperature −10°C to 50°C ±0.3°C |
| Short Quickstick (POL8751) | 0–10% RH ±3% at 25°C; 10–70% RH ±2%; 70–99% RH ±3%. Temperature 0°C to 50°C ±0.5°C |
| Surface temperature – plug-in probe | −20°C to 80°C, accuracy ±1.5°C |
| Surface temperature – infrared | −10°C to 50°C, accuracy ±2°C at 25°C. Laser pointer, 12:1 distance-to-spot ratio |
| Data logging | User-set interval from 1 minute to 24 hours, downloadable to PC software |
| Operating conditions | 0°C to 50°C, 0–95% RH non-condensing |
| Display | 2.0″ colour graphical LCD, 176 × 220, adjustable backlight |
| Power | 9 V alkaline battery, 550 mAh |
| Size | 177 × 80 × 38 mm |
| Gross weight | 182 g (instrument only) |
| Regulatory compliance | CE, RoHS, ETL |
| Warranty | 24 months on the instrument. Excludes wear on accessories and consumables |
Concrete floor moisture measurement
The HygroMaster 2 is used for both recognised approaches to slab moisture, and they are not interchangeable.
- In-situ (sub-surface) relative humidity — a hole is drilled, sleeved and left to equilibrate, then read with a Hygrostick on an extension lead. This is the method behind ASTM F2170 and BS 8201 / BS 8203. Protimeter developed the sleeve test.
- Surface equilibrium relative humidity — a humidity box is sealed to the slab surface and left to equilibrate. Non-destructive, but it reports the surface condition, not the moisture held deeper in the slab.
A floor laid on the strength of the wrong test only reveals the problem when it lifts. Confirm which test the flooring manufacturer's warranty requires before you drill.
Accessories
- Plug-in surface temperature sensor (BLD5808) — contact readings against dew point, more reliable than infrared on glass, gloss paint and polished tile
- Hygrostick extension lead, 800 mm (BLD5802) — lets the sensor sit in a sleeved hole while you hold the instrument
- Humidity box (BLD4711) — surface equilibrium RH on concrete floors, non-destructive
- Adjustable humidity sleeves (BLD4650-20) and original style sleeves (BLD4902) — for in-situ testing in drilled holes
- 300 mm humidity and temperature probe (BLD8755) — reaches into ducts, voids and cavities
- USB cable and logging software (BLD7758)
Frequently asked questions
What is the difference between the HygroMaster 2 and the HygroMaster L?
The L is the lighter, simpler version. The HygroMaster 2 adds data logging with a user-set interval, PC download, and a built-in infrared surface thermometer with laser pointer. If you need to leave the instrument recording, or you report surface temperature against dew point, the 2 is the one.
Does it measure moisture in timber or plaster?
No. The HygroMaster 2 is a hygrometer, not a moisture meter. It measures the air and the surface, not moisture content inside a material. For material moisture you need a pin or non-invasive meter such as the MMS3, which combines both.
Which sensor comes in the box?
It depends on the part number, and the sensors are not interchangeable in performance. See the comparison above, and check the kit contents on this page before ordering.
Can I use it for ASTM F2170 concrete testing?
Yes, with a Hygrostick, an extension lead and sleeves. The instrument alone is not enough — the hole has to be drilled, sleeved and left to equilibrate.
How often should it be calibrated?
Twelve months is a sensible starting interval, adjusted to your own work environment and quality procedures. Humidity sensors are replaced rather than recalibrated; conformance certification for the instrument is available in Australia.
The reading seems slow to settle. Is it faulty?
Usually not. A Hygrostick is deliberately slow and stable; it can take considerable time to equilibrate, particularly moving from a wet environment to a dry one. If you need fast spot readings, that is what the Quickstick is for.
Care and maintenance
- Treat humidity sensors as consumables. They drift with age, contamination and prolonged saturation — replace rather than attempt to recalibrate
- Remove the 9 V battery if the instrument is going into storage for an extended period
- Do not leave a Hygrostick sitting in a saturated hole indefinitely; retrieve it once the reading has stabilised
- Keep the infrared lens clean and free of dust. A smeared lens reads low
- Clean with a dry cloth only. Do not use solvents on the display or the sensor
Documents
- HygroMaster 2 instruction manual (INS7750 Rev B, September 2024)
- HygroMaster 2 datasheet (AAS-920-081H, September 2024)
Where the datasheet and the instruction manual disagree, the manual is the current document and the figures on this page follow it.
Not sure whether you need a Hygrostick or a Quickstick, or which kit covers the testing you do? Contact Carpet Cleaners Warehouse before ordering and we will confirm the right configuration.
