Problem really is my husband. I remember years ago listening to you radio show and either you or your brother (may he rest in peace) stated that the heater should not be turned on until the motor had registered that it was warming up. My husband doesn’t believe it. Is that still the case?
No , even cold air can help with defrosters . And apparently you are asking Ray this question and I don’t think he ever replies here . And modern vehicles just don’t take that long to warm up.
My 2013 Equinox warms quick enough that I just leave heater fan on at a low speed. Not anything to be concerned about.
I leave the heater fan off or on the lowest speed during engine warm up, it only takes 2 miles. Allowing the engine to reach operating temperature before taking heat away with the heater is a more efficient operating procedure.
Many cars automatically wait for the coolant to start getting warm before turning on the blower. If your car doesn’t do this, this is mostly a question of comfort, so it’s hard to say that it’s “wrong” to turn it on earlier than that.
As noted above, cars do warm up more quickly today than years ago. Also, as noted above, if you need the defroster to see safely, then you do want the air blowing right away, even when it’s still pretty cold.
if you set the temperature for the system, it has automatic controls, and will probably recognize that the SUV just started. As @lion9car said, it will monitor the coolant and increase the fan speed when the coolant provides heat. I see this as a convenience feature and has no effect on any car components. You can’t pull so much heat away from the coolant that it will never warm up.
There’s no mechanical advantage or disadvantage to either way. The correct way is whichever makes you comfortable faster and defrosts the windshield faster.
But the Tappet brothers were well aware that in a male/female difference of opinion the man was always wrong.
It kinda depends. Cold air is okay for defogging your windshield but it won’t really help much with defrosting. And think about it. Do you really want cold heat? Do you heat your house by opening the windows? I normally wait until the temperature needle moves a bit before I turn on heat but it won’t hurt anything to turn it on earlier.
Maybe the old days were better with the Stewart-Warner Southwind gasoline heater. With this heater, you had instant heat. The first Corvair, which was the 1960 model, had a gasoline heater. The next year, the Corvair was heated with hot air off the exhaust manifold. I believe some Chrysler products in the late 1950s offered a gasoline heater as an option. With electric cars, we may have to go to some sort of fossil fuel heat.
At any rate, if you want instant heat, have an engine block heater installed. It will run up your electric bill, but you will have instant heat.
Actually it is true. This may have been the question, asked by the man who did not agree with his wife and Tom replied: before I answer this, which is more important to you, to be right or to be happy?
I don’t remember which side he was on but they did say that it is very insignificant. Modern engines use the heater core as a thermostat bypass so when the thermostat is closed to keep coolant from flowing through the radiator, it does flow through the heater core so that there is some coolant circulation in the motor. Without some circulation, the motor would heat up unevenly and shorten its life.
When you turn on the fan, you are drawing some of the heat from the cooling system causing the motor to take longer to warm up. This uses a little more gas and increases the pollutants from the motor. BUT, the amount of time it adds to the warm up cycle is actually pretty insignificant. As long as the fan is not on its highest setting, the change in time to heat would probably take some pretty sensitive instruments to measure.
Now which is more important to you, to be right or to be happy?
My 83 caddy had temp controlled fan. Would not spin up when cold.
I think that is true of all modern vehicles with automatic climate control.