| Measurement output seems incorrect |
Installation location is not representative of actual conditions you
want to measure |
Verify the installation location and relocate the probe if
necessary. |
| Heat conduction along probe head and cable is interfering with
measurement accuracy |
Follow the installation recommendations for cases when temperature
of measured environment differs greatly from ambient. See Installation. |
| Probe is in need of adjustment |
Calibrate and adjust the probe. |
| Probe status indicator LED is red |
Probe is in error state |
Connect the probe to Insight software or an Indigo transmitter and
read the error message(s). See Vaisala Insight software and Error messages. |
| Probe status indicator LED is off even though power is on |
Probe model is HMP1, or HMP3/HMP7 with a 0.15‑m (0.49‑ft) probe connection
cable. |
To prevent the warming of the indicator LED from causing a slight measurement
error, HMP1 probes keep the indicator normally off (even when power is on). If the
probe is in error state, the red LED is shown. The same applies to HMP3 and HMP7
probes with a 0.15‑m (0.49‑ft) probe connection cable. |
| Values of measurement parameters stop changing for a few
minutes |
Probe is performing a sensor heating function such as sensor purge or waiting for
the sensor to cool down |
Wait for the function to complete and measurement parameters to be available
again. |