The Delmhorst HT-4000 is a stand-alone thermo-hygrometer for water damage technicians, building inspectors, flooring contractors and HVAC trades. 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 crews prefer separate tools — one person on moisture readings and another logging atmospheric conditions, or simply not wanting the whole job to stop when one meter goes back for service. That is what this instrument 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 |
| Warranty |
1 year (owner's manual) |
What it is for
Atmospheric readings drive drying and acclimatisation decisions. Dew point tells you whether condensation is about to form on a cold surface, and grains per pound tells you whether the air going into a structure is actually drier than the air already there. Running dehumidifiers or acclimatising a floor 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 the 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
The Moisture Meter Company (Aberford Holdings Pty Ltd) is the exclusive Australian distributor for Delmhorst non-agricultural moisture meters. Service, calibration questions and warranty claims are handled here rather than sent overseas.
One year warranty on manufacturing defects (owner's manual). 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.
What we see in the field
Don't take your room reading next to the dehumidifier outlet. Or in the doorway with the outside air coming through. Give the sensor time to settle where the work is being done, then compare the same locations on the next visit.
Documents
Not sure which meter or electrode suits your work? Tell us what you are testing — drying jobs, slab acclimatisation, HVAC checks, inspections — and we will recommend what you need. See the full range in Delmhorst Moisture Meters.
