Connect with us

Help me design a water heater circuit that automatically turns-off when the heater reaches a boiling

Discussion in 'General Electronics Discussion' started by Christine Al, Mar 19, 2017.

Scroll to continue with content
  1. Christine Al

    Christine Al

    1
    0
    Mar 19, 2017
    Help me design a water heater circuit that automatically turns off when the heater reaches a bouling point of 100 degrees centigrade and automatically turns-on when it cooled down about 80 degrees centigrade, include a potentiometer to calibrate the temperature
     
  2. Minder

    Minder

    2,955
    624
    Apr 24, 2015
    Use a SSR to control the immersion htr and a thermostat in the low voltage side.
    Alternatively you could use a relay in place of the SSR.
    M.
     
  3. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    25,387
    2,772
    Jan 21, 2010
    You need to be very careful about setting the upper temperature to 100°C. If inaccuracies or drift cause it to increase, you may have the problem of it not turning off.

    Setting the upper limit to (say) 95°C can save you headaches and energy.

    Heating water is not exactly exotic, you may be able to find a mechanical thermostat which will do what you want relatively cheaply and certainly more easily.
     
  4. Audioguru

    Audioguru

    2,834
    634
    Sep 24, 2016
    My electric kettle has a fine screen that blocks steam at the spout and when the steam pressure is high enough it pushes the switch off. Then it is not affected by altitude. But it doesn't turn itself on again.
     
  5. Externet

    Externet

    737
    159
    Aug 24, 2009
  6. 32Vwasbetteronboats

    32Vwasbetteronboats

    80
    6
    Feb 18, 2017
  7. duke37

    duke37

    5,361
    767
    Jan 9, 2011
    All electric Kettles I have seen have a thermal switch above the water. This does not switch off untjl it is heated by steam thus a temperature setting of about 95C is good enough.
    The switch is an overcentre type and needs to be reset. This is to allow a fast contact break. The one I use now will only reset in mains is present.

    I would not play with a switch immersed in water or steam.
     
  8. kellys_eye

    kellys_eye

    4,276
    1,146
    Jun 25, 2010
    Shouldn't this be in the 'homework' section?
     
  9. AnalogKid

    AnalogKid

    2,361
    659
    Jun 10, 2015
    Help you, or give you? Show us what you've got so far.

    ak
     
    davenn likes this.
  10. Rixen

    Rixen

    98
    23
    Feb 16, 2016
    I made this thermometer circuit in the previous years school term, you could quite easily modify/add stuff to do what you want..

    [​IMG]
     
  11. davenn

    davenn Moderator

    13,589
    1,871
    Sep 5, 2009

    no
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-