Filled system thermometers are most often seen in home
cooking ranges, at least in North America They look like a long, thin metal tube
with a thicker tube, almost a bulb at the termination in the heating region. They
are simple, require no electrical power and last almost indefintely, as long as
the metal tubing is not broken or pinched shut along its length. They
are sometimes also called gas thermometers, or pressure thermometers, because
they operate on the principle that a gas expands or contracts in a known fashion
due to a change in its temperature. They have many useful places
in industry and commerce in addition to home cooking ranges. Wherever low to moderate
precision is required and trouble-free, long life and freedom from power sources
is required, you'll often find these types of devices. They are
made and supplied by a number of vendors and this page is just getting started,
so bear with us as we slowly add to the list of vendors. If your company is not
listed, let us know so it can be. | 
