what does the thermostat measure?(furnace)

Discussion in 'The Watercooler' started by ctmom05, Dec 20, 2008.

  1. ctmom05

    ctmom05 Member

    Our furnace is in the basement; the thermostat is upstairs in the hallway. What exactly is the thermostat measuring?

    My guess is that it is measuring the air temp around where the thermostat is placed and sending a signal to the furnace to tell it when heat is needed.
  2. klmno

    klmno Active Member

    That is correct. Of course, you set the thermostat where you want the lowest or highest temperature. I've made the mistake before of forgetting to switch the thing from air conditioning to heat then wondering why it wasn't working. They don't all have a switch- depending on your system and thermostat, but some do.
  3. goldenguru

    goldenguru Active Member

    Actually the thermostat in my house measures how many hundreds of dollars it costs me every month to not freeze to death. Lately the measurements have been quite considerable.

  4. skeeter

    skeeter New Member

    totally depends on the type of furnace you have....

    But in principle, the thermostat is a thermometer and an switch. When the temperature falls below the "set" temperature, the switch changes and sends a signal to your furnace. This signal will either light a pilot light, light a furnace grate, turn on burners, however your furnace heats. Once the "system" gets to a set temperature (there's usually another thermostat somewhere on the system), the blower will go on, the pump will start circulating the water, whatever your system is.

    The thermostat that started all this will again send a signal when the temperature rises above the setting. This will turn off the blower, pump, grates, pilot light, whatever.

    On the older dial thermostats, you only have an option of setting one temperature. On programmable ones, you can set numerous temperatures based on time, etc. such as lower for night, higher for day.

    And, of course, the thermostat works the opposite way with air conditioning / cooling.