When I go to open the door to the refrigerator, there is a chance that if the motor is running, it will stop when I open the door, or if the motor is not running, that it will start when I open the door. This isn’t just with my fridge, but others’ as well. It’s not so common that the occurrence itself amazes me, but the timing. If there is a switch in the operational state of the motor, it occurs exactly at the same time as I open the door. Never a little before, rarely a little bit after (but if it does happen after, it’s when the door slams shut).
Is there some mechanism in the fridge that, upon being subject to the slight jostle of a door opening, will switch the state of operation of the motor?
There is a switch that controls the light (if you look for it, you’ll find it somewhere near the front of the fridge). There is also a switch that controls the motor. Dunno off the top of my head where it is, or if it’s connected to the light switch, but it’s there.
It may be that the motor is switched off by the same sensor that turns the light on; possible reasons for this might include:
-The manufacturer does not want the motor to run continuously, as would happen if you left the door open all the time.
-So you can defrost it.
-To avoid the possibility of running the motor and light simultaneously and blowing the fuse - (Unlikely, I think).
The motor is thermostatically controlled. It switches on and off according to temperature.
A very simple and very common temperature switch is made using two bonded strips of metal (a bimetallic switch). It look something like this.
The force imparted by the opening of the door could be enough to make the switch change states, if it was almost about to, anyway. The motion just hastens the operation.
Or it could be that the slight jostle of opening/closing the door is enough to push the thermostat over it’s threshold, either way. There is often considerable hysteresis, so once it gets ‘carried over’ to the other state, it’s more likelly to stay there.
I’m sorry - perhaps my clarity left a little something to be desired. A change in operating state of the motor only occurs maybe 5 to 10% of the time. The rest of the time, when the door is opened, the state of the motor does not change. If it was running, it continues running - if it was not, it does not start.
So it’s not like there is something like a physical switch responding to the movement of the door, because the action is not consistent. However, for that 5% to 10% of the time, the timing of the state of change, as I had said, is almost exactly in time with the initial movement of the door. I appreciate your answers thus far, but it seems that your understanding is that the door opening turns off the motor, and that is not the case, strictly speaking.
We posted at the same time, but to amplify, opening the door could sometimes (say, 5-10% of the time ) cause the air temperature to drop enough to trip the motor on. Opening the door per se would never cause a running motor to turn off, AFAIK.
This is correct and can easily be proven: every time before you open or close the door, first knock on the fridge hard enough to make the same thing happen, then open the door. You will see it is the knock and not the door opening which makes it happen.
Thank you all for your quick responses. I was writing my second post as Desmostylus was posting. I think that that response was the one that is most likely giving me the answer I was seeking.
) cause the air temperature to drop enough to trip the motor on. Opening the door per se would never cause a running motor to turn off, AFAIK.