Things people don't understand - Thermostats

Posted on Sun 30 October 2005 in Root Observations

Have you ever noticed how some times people don't operate an appliance/machine properly because they don't understand how it works? Often, it's because they've never been told or seen an instruction book. There are probably a lot of things I think I know how to use, but don't.

One of the most annoying things I find that people don't know how to work are thermostats. You know, the device that turns your heating on in your house or office. Thermostats have a scale of temperatures, the one in the photo goes from about 4 degrees centigrade to 32 degrees centigrade. 4 degrees means that it will turn on to prevent frost, 32 degrees is probably too hot for comfort.

What do you do when you feel cold? Most people turn the thermostat up, but in reality that probably isn't a solution. A thermostat will turn the heating on when the temperature falls below the temperature it is set too, and it will turn off when it goes over that temperature.

So, you get into work in the morning and it feels cold. The temperature on the termostat is set to 22 Degrees. It seems most people will then turn it up to 30 degrees. When I ask why they say "because its cold and it will warm the room up quicker". This is the point - it wont warm the room up any quicker. The heating system output is unchanged by the thermostat - a thermostat sets the heating on or off. All that will happen is that eventually the room will heat up to 30 degrees at which point someone will walk over to the thermostat and turn it down. Typically they turn it down to 16 degrees, no doubt thinking it will cool the room down quicker. When the temperature eventually reaches 16 degrees people will be cold and turning it back to 30 degress.... and on it goes.

If you feel cold when you get into work in the morning (or home at night for that matter) the problem isn't the thermostat not turning on the heating when the temperature falls below it's setting (22 degrees in this case) - it's probably that the heating system has an overideing on/off switch on a timer, so the office isn't heated overnight and the house isn't heated during the day when it's empty. The solution is to change the timer to turn the heating on before people get into work/get home. Once the room is at 22 degrees the thermostat will turn the heating off by itself. Perhaps these graphs will explain it better:

i-e1e7ee729de25e4a500317619019c17b-tempgraph1_web.png

i-dff0377d4b73cf87f850990621d771f3-tempgraph2_web.png

So why are we able to set the temperature then?
As humans we prefer different temperatures for different activities, doing the house work will probably warm our bodies up and therefore we will prefer a cooler ambient temperature (say 18degrees). Sitting down at night to watch a movie and we may prefer it slightly warmer (say 24 degrees). Working in an office with little movement we may prefer 22 degrees, whereas working on a trade counter which involves a lot of movement we will probably prefer 20 degrees. Every day we prefer something slightly different, and that's why we have the control of a thermostat through a range of temperatures. Including a "Frost Protection" setting of around 4 degrees, for when the office is closed over christmas and we wouldn't want pipes to freeze in our absence.

So, the next time you feel cold at home or the office, don't jump up and put the thermostat on it's maximum setting, move it up by a couple of degrees then go and check to see the heating timer is set correctly.