Who can help me to understand how AC thermostats work? Does keeping the T @ 18C make the room more cooler?

Question

Also help me understand how the thermostats work in those machines which heat the bread, I dont know what they are called, Hehe.

I was having an arguement with my dad regarding the science behind thermostats. My dad was saying thermostats operate on a timer inside, he even said the thermostat is a timer itself, where as I said a thermostat control the flow of energy. My dad says that keeping the AC temperature at 18C doesnt cool the room faster instead it allows the compressor to run non-stop for a longer period of time. From his statement, I concluded that look dad, when the compressor runs non-stop for a set period of time, the room will cool much faster.

Well, its all upto to you guys on Yahoo Answers to help me out of this thermostat mystery. Thanks

Answer 1

PPK is on par for thermostats. the ability of an AC to cool or heat a given space,depends on its BTU,or TONNAGE.

ie; a smaller ac will run longer,cooling a room,than a larger one.

a small ac unit might not be able to compensate for the amount

of heat absorbed by a given space.(it could run continuously.)

Answer 2

Thermostats turn on the AC if the temperature goes above whatever temperature you set it to. Old ones use bimetallic strips, but newer ones use a digital thermometer. Works the same way but the other way around for heating.

Answer 3

  Most air conditioners are fixed output (we have one with a high and a low output, so it cruises when it is maintaining temp), so lowering the temp doesn't make it cool faster - there is no more than the available cool so matter what the setting.  

  Toasters normally have only a bimetalic strip so that when you push the toast down, the elements start heating the toast and the toaster at a fixed rate.  When it gets hot enough, the strip bends far enough and releases the toast and cuts off power.  Toast done after the first batch toasts faster because less heat is lost heating the toaster so temperature rises faster and cooks toast faster.  Some expensive toasters have photo cell detection of brownness, but none use a straight timer.