Jun 06, 2023
This is an old one. A winter automotive puzzler. Here we go.
This was years ago, before there were EVs and plug in cars.
It was a cold, cold winter up here in New England. So cold, you felt like you could freeze in place if you were standing outside.
So my neighbor tells me that his heat isn't working in his car. So we talk about it and the possible things that could be wrong. So I said maybe he was out of coolant. And he said no, that, wasn't it. And then I said, what about the heater core, could it be plugged up? And again, he said no.
Anyway, we figure out together that he needs a thermostat. So, he goes and tries to put in a new thermostat, to see if he can fix the problem himself.
So there he is in his driveway, and it is a crazy cold day. So he puts in his thermostat. And when you install a thermostat, you also have to refill the cooling system, because you lose a lot of it during the installation process. And then you have to run the engine, to get the coolant to circulate, so you can get all the air out of the system. So he is doing this. And he keeps doing it, for a long time. So finally, I come over and ask him what is going on.
And he says, he doesn't know and asks me what could possibly be wrong with it. So, I look over at this car, and it is running, and I guess he was afraid to lock his keys in his car because he has the window wide open.
So I told him to roll up the window and he'll be all set. He did. And that solved his problem.
So the question is very simple, why did I tell him to close the window?
So, winter puzzler answer time.
Recap, my nieghbors car, heat didn't work. He replaced the thermostat, but couldn't get it to work. So, I told him to close the open window.
Why did it work when I told my neighbor to roll up his window?
So because his heater had been on all winter long with not working, when you finally put the thermostat in and the heater of course was not working, the heater was acting as the radiator. And because it was so cold and the window was open, the thermostat never had to open because the coolant was just circulating into the heater, which was cooling it off so that by the time I got back to the engine, it was so cooled off it never heated up enough to open the thermostat.
And the thermostat doesn't open until the temperature of the coolant gets up to like 180, 190 degrees. But it will never open if the stuff doesn't get warm.
So he closed the window which finally allowed the passenger compartment to heat up and then once that heated up, the coolant no longer had to do this double duty of heating all the air in the neighborhood.
