Most barometers need little attention once they are set up and working. Some Banjo barometers may need to be "tapped" lightly with your finger to engage the string pulley system and free up any needle resistance, to get an accurate reading. Stick barometers are relatively service free, however, should the mercury or mercury tube get dirty and result in increased resistance within the tube, they too may need to be tapped to perform accurately.
Initial calibration to record barometric pressure is required at start up. Any local airport will have an accurate barometer for you to get a current air pressure reading from. Calibrating the mercury type barometer does require some expertise, so I shall not include that information here.
were designed to be used at sea level. For those of you that live much above
sea level, a certain degree of adjustment is necessary to account for the decrease
in air pressure at high altitude. Barometers can be located anywhere in the
home, but should be located out of the direct sunlight. Direct sunlight will
prematurely age the wood and give false readings, as mercury will expand due
to heat. It is not necessary to locate the barometer near a window, as air pressure
is equal anywhere in a home. But do locate these units out of the way of heavy
traffic, children, or pets.