Umpteen months ago my Davis anemometer/wind gauge stopped working properly. As it was on a pole attached to the solar water heater, high up on the roof at a guestimated 12 -13 m and because my age did not permit me to do rooftop gymnastics, I bought an Aercus system. This past week or so, a technician from our CH co. had to go up on the roof and I asked him to bring down the pole/anemometer. I found that both the wind speed and direction system was bunged up with a very fine dust which rain had hardened into a cement (we often get excessive very fine dust storms blown in from the Sahara, exceeding all PM10 and PM2.5 levels). This deposit had hindered the movements of the instrument. I tried to remove as much as possible (wet toothbrush). It now works; the anemometer is fine and it calibrates well with the Aercus (in fact, the Davis is slightly higher on gusts, but it is about 1.5 m higher), bearing in mind the different time scales. However, the vane is still slightly sticky, but this is not a real problem as it fails to register only on slight summer zephyrs; any wind over 1 m/s moves it.
As the Davis is now ‘all systems go’ again (except for UV), I’ll now reconfigure it as the main system, with our forecasts.