The Delmhorst HT-4000 is a stand-alone thermo-hygrometer. It uses the same fast-acclimating RH and temperature sensor fitted to the Navigator Pro, but as a separate instrument rather than part of a combination meter.
Some contractors prefer separate tools — one person on moisture readings, another logging atmospheric conditions, or simply not wanting the whole job to stop when one meter goes back for service. That is what this is for.
Specifications
| Relative humidity | 0% to 100% |
| Temperature | −40 °C to 124 °C |
| Dew point | −40 °C to 80 °C |
| Grains per pound | 0.1 to 3,820 GPP |
| Grains per kilogram | 0.01 to 545 GPK |
| Vapour pressure | 0 to 47 kPa |
| Display | Digital with backlight |
| Hold | Reading hold for awkward positions |
| Auto off | Battery saving timer |
| Size | 216 × 86 × 44 mm |
| Weight | 312 g |
| Case | Hard carrying case included |
What it is for
Atmospheric readings drive drying decisions. Dew point tells you whether you are about to get condensation on a cold surface, and grains per pound tells you whether the air you are pushing into a structure is actually drier than the air already in it. Running dehumidifiers without those numbers is guesswork.
Frequently asked questions
Do I need this if I have a 3-in-1?
No — the TotalCheck and Navigator Pro include the same class of sensor. The HT-4000 suits crews who want a dedicated instrument, or a second one so two people can work at once.
Does it measure material moisture?
No. It reads air only — humidity, temperature and the values derived from them. For moisture in timber, drywall or concrete you need a pin or pinless meter.
What is GPP for?
Grains per pound is absolute moisture in the air. Comparing GPP inside and outside tells you whether ventilating will dry the structure or wet it further — relative humidity alone cannot answer that.
Support and warranty
Carpet Cleaners Warehouse is the exclusive Australian distributor for Delmhorst outside the agricultural sector. Service, calibration questions and warranty claims are handled here rather than sent overseas, and we hold electrodes and pins in stock.
Two year warranty on manufacturing defects. This does not exclude, restrict or modify your rights under the Australian Consumer Law. Our goods come with guarantees that cannot be excluded under the ACL. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage.
From the workshop
[Technician’s Note — replace before publishing: two to four sentences of first-hand CCW field experience relevant to this product. A pattern you see, a mistake customers make, or something learned from servicing or selling it. Not spec repetition, not a sales pitch, not invented.]
Documents
Not sure which package or electrode suits your work? Tell us what you are reading — timber floors, wall cavities, concrete, cladding — and we will tell you what you actually need. More in Moisture Meters.
