thermostat

Definitions

  • WordNet 3.6
    • v thermostat control the temperature with a thermostat
    • n thermostat a regulator for automatically regulating temperature by starting or stopping the supply of heat
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Webster's Revised Unabridged Dictionary
    • n Thermostat (Physics) A device which automatically regulates temperature, or provides a signal used by another device to regulate temperature. The temperature-sensitive signal may be electronic, as that produced by a thermocouple. The signal may also be caused mechanically, as by the unequal expansion of different metals, liquids, or gases by heat, which can then cause the opening or closing of the damper of a stove, or the like, as the heat becomes greater or less than is desired.
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Century Dictionary and Cyclopedia
    • n thermostat An automatic instrument or apparatus for regulating temperature. It is essentially a modification of the thermometer, so arranged that, in place of indicating thermal variations, it controls the source of heat or of ventilation, and thus indirectly regulates the temperature. One of the earliest forms of thermostat was that devised by Dr. Ure. It consisted of a bar composed of two metals, say steel and copper, having different degrees of expansion under the same temperature. This bar, when fixed in position, was made by simple mechanical means to open a furnace-door, move a damper, or open a window, by means of the bending of the bar under the influence of an increase in heat. Other forms of this thermostat have since been used to make or break an electric current, and thus move an armature that controls a damper, steam-valve, or other heat-regulating mechanism. Another form consists of a balanced thermometer that, under the movements of the mercury in a tube pivoted in the center in a horizontal position, would rise or fall, and thus control a damper or fire-door. Another form consists of a thermometer resembling a thermoelectric alarm (see thermo-electric), except that the closing of the circuit by the rise of the mercury in the tube operates a fire-door or damper in place of sounding an alarm. Where a thermostat is merely used to ring a bell, it is called a thermostatic alarm. A very simple and yet delicately responsive form is a slender bar of gutta-percha, fixed at one end, and attached at the other to a lever, which is caused to act by the expansion or contraction of the bar. Another form of thermostat consists of a bent tube partly filled with mercury. The heat expands the air in the larger end of the tube and displaces the mercury, and this in turn moves a piston controlling, by means of some mechanical device, a steam-valve or damper. Another form, used with steam-heating furnaces, consists of an elastic diaphragm in a cylinder, the pressure of the steam against the diaphragm serving to move a piston that controls the damper of the furnace. Such appliances are also called heat-regulators. More recently, the name has been given to fusible plugs used to control automatic sprinklers, a rise in the temperature causing the plug to melt and release the water. This, however, is only a trade use of the word.
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Chambers's Twentieth Century Dictionary
    • n Thermostat an appliance for showing temperatures automatically by the expansion of substances—used in regulating steam pressures, &c
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Etymology

Webster's Revised Unabridged Dictionary
Thermo-, + Gr. to make to stand
Chambers's Twentieth Century Dictionary
Gr. thermos, hot—thermē, heat—therein, to heat.

Usage

In literature:

The thermostat is a device that automatically regulates the heat of the oven.
"Woman's Institute Library of Cookery, Vol. 1" by Woman's Institute of Domestic Arts and Sciences
A thermostat regulates the heat.
"If You're Going to Live in the Country" by Thomas H. Ormsbee and Richmond Huntley
He turned his oxygen down to the bare minimum and the thermostat as low as he dared.
"Far from Home" by J.A. Taylor
A thermostat can be placed on the system and the temperature of the water controlled.
"Elements of Plumbing" by Samuel Dibble
It is well to have the temperature of a dry kiln controlled by a thermostat which actuates the valve on the main steam supply pipe.
"Seasoning of Wood" by Joseph B. Wagner
Stopper and keep at room temperature three hours, then in thermostat at 50 deg.
"The Elements of Bacteriological Technique" by John William Henry Eyre
This thermostat is set at 60 deg.
"Respiration Calorimeters for Studying the Respiratory Exchange and Energy Transformations of Man" by Francis Gano Benedict
The mechanoids did not have thermostat stations, for they did not need them.
"The Genius" by Con Pederson
He adjusted a thermostat on the wall, to seventy degrees.
"Whispering Wires" by Henry Leverage
The temperature of the thermostat is then raised degree by degree, and the height of the meniscus at each point ascertained.
"The Phase Rule and Its Applications" by Alexander Findlay
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In news:

At $250 a pop, Nest units are five to 10 times the price of standard programmable thermostats .
The Second-Generation Nest Thermostat .
Second Generation Nest Learning Thermostat , Image: Nest.
IPhone-Controlled Thermostat From Creator of the iPod.
If your house is less than 20 years old, you probably have a programmable thermostat .
People don't buy thermostats .
When do consumers get new thermostats .
Model T1900 Slimline Platinum residential thermostat has a built-in humidity module, which allows the thermostat to not only automatically control temperature but humidity as well.
Programmable thermostats are a great investment.
Many programmable thermostats cost less than $90, so you're likely to recoup your investment quickly in lower energy bills.
Unlike thermostats that operate with mercury, leveling a digital thermostat isn't necessary, but it looks better.
Nuheat introduces its new Energy Star rated Solo programmable thermostat .
IPod Creator Introduces Cute Home Thermostat That Learns Your Habits.
Programmable thermostats have been been on the market for years, but they are as fun to program as early VCRs.
Because traditional thermostats are so hard to program, few people adjust the temperature to fit their schedules.
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In science:

These divergences indicate that the simple-minded thermostat is unphysical.
Derivation of a non-objective Oldroyd model from the Boltzmann equation
Because the thermostat will regulate the temperature without influencing the stress we can have a second moment Πxx = Z fv (vx − ux )2 that becomes negative which in terms reqires negative contributions to the probability distribution.
Derivation of a non-objective Oldroyd model from the Boltzmann equation
This is what makes the thermostat unphysical.
Derivation of a non-objective Oldroyd model from the Boltzmann equation
Nevertheless Hawking suggested that taking a black hole together with radiation of the same temperature and putting them into a thermostat should provide a system in thermodynamical equilibrium.
Black Hole Statistical Physics: Entropy
Let δI = I − I ∗ and δβ = ˜β − β be dispersions of the fundamental physical quantities I of the interest system and the effective canonical parameters ˜β of the generalized thermostat respectively.
Generalized Fluctuation Theory based on the reparametrization invariance of the microcanonical ensemble
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