For those without Automatic Climate Control, when do you turn on the heat?

My saturns used to suck all the heat out of the engine too if I ran the fan too high. And I did maintain their awful thermostats, even used cardboard acrosss the radiator.

Current scheme is to run the heat on full hot, or the desired 72 on ATC, but with the fan on low. When the engine warms up I boost the fan temp. I never use recirculate so that extra heat is just blowing out the rear vent flaps in the trunk.
 
Once the water temperature gauge needle has moved any noticeable amount from minimum stop, which would correspond to somewhere in the ballpark of 125°F water temperature. Turning it on sooner means I'm just blowing cold air onto myself while slightly prolonging the warm-up time.
 
On my subaru the heat comes in at 86 degrees F oil temp.On a 30 degree day that is 1.5 miles low speed.
I would not worry one iota about it. You are overthinking it. The oil is circulating. Thats all the engine needs.
 
Most auto systems leave fan speeds low until a minimum temp. is reached then system ramps up blower speeds.
Auto on with remote starts directs more airflow onto the windshield.
US vehicles will override the Recirculation feature to de fog windows in defrost. Not so in Asian cars. Take notice in winter of which brands have side windows fogged up driving around. Especially on interstates where we know the engine is up to temp and not just started 5 min. ago.
 
That is one option I do wish I had this time of year :)
Do not use mine much cuz I keep forgetting I have them, you know 1st vehicle with them. A cold night around 0° when leaving the lady friends house will have you remembering. They are nice. I like the heating steering wheel better. When my hands are warm I am happier.

To stay on topic, one button turns the HVAC on. When I leave the heated garage I can usually make it to the shopping district without getting chilly. When getting back in the truck it still has warm coolant, that is when I turn the heat on. Turning on the heat when cold does nothing for heat in the truck. Seems I need to wait until the coolant needle starts to rise.
 
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I can’t speak for all makes but on the Chev Suburban and Ford Taurus, there is no “ valve” that lets hot water through the heater core. It always flows through the heater core. Instead, a flapper door opens to let hot air into the passenger compartment. On automatic systems the computer controls the flapper. On manual systems, turning the dial controls the flapper.
This... if your temperature valve actually cuts the flow of coolant through the heater core, this will help engine warm up. But I haven't seen that type of system in decades -- my 1972 Gremlin had this. Nowadays most cars have coolant flowing through the heater core at all times, flow cannot be shut off, and the heat valve only changes the airflow across the core. So I can't see how shutting off cabin heat could significantly help engine warmup.
I have done a few experiments of my own. My morning routine is extremely consistent and ambient temperatures at 5:30am can be within a few degrees for weeks at a time. I would alternate every morning between heat on full and heat off, otherwise my cold start idle times were the same and driving style the same, etc. I could tell absolutely no difference in warmup time between heat on vs heat off. May be un-scientific but I've done this many times over the years and never saw any difference. So I leave the heat on when it's cold and turn it down when it's a warmer day 🤣
 
The "auto" fan setting on my 2021 F150 is terrible, so I never use it. It keeps the fan off until the engine is warm, then blasts it at the highest setting. I prefer to leave it on a low setting all the time; only crank the fan up if it's really cold or hot.
 
I have a 10 year old BMW diesel that has a 1000 watt electric heater to throw cabin heat before the engine warms up. That additional alternator load makes the engine warm up even faster.

With that, the heated seats, the heated steering wheel.........no wonder its a 220 amp alternator
 
My last daily had automatic climate control, and the blower delay was probably my favorite part of that system.

Now, with the manual climate control in the Camry, I typically turn the fan up a bit (from low - I never really turn the fan completely off) at around 2-3 minutes after starting the car/starting to drive (I rarely warm up the car more than a few seconds, maybe a minute or so if it’s particularly cold). This seems to correspond to a coolant temp in the low 100f range, which is when the temp gauge starts to move off of “C” towards the normal position. The car typically hits the midpoint of the temp gauge after 5ish minutes of driving (at speeds of 35-45mph), which coincides with when I typically get to the freeway and speeds increase. At that point, there is ample heat.
 
I usually wait until the needle moves a couple of widths. Then the air feels warm. I don’t care for cold air blowing at me. Start up, turn fan off, turn heat to max, buckle up and go. Turn heat once the gauge has moved a bit.

I will put on defrost as needed, but then I hop out and start scraping. Then I get back in and crack a window open before taking off, lest it freeze up inside.

The faster I get the car going, the faster I get heat from the heater.
 
I turn the heat on once the the temperature gauge starts moving. Also, I must be the only person who couldn't care less about heated seats. Maybe it's different with leather, but for me even if it's -15C I never feel the need to turn them on. It's my hands, feet, and face that are freezing so I warming my butt doesn't fix that.
 
I turn the heat on once the the temperature gauge starts moving. Also, I must be the only person who couldn't care less about heated seats. Maybe it's different with leather, but for me even if it's -15C I never feel the need to turn them on. It's my hands, feet, and face that are freezing so I warming my butt doesn't fix that.
Its different with leather, and it can be oh so nice when ones back is sore.

My wife really wanted a heated steering wheel in her new car, but we couldn’t find one optioned that way. Next car, hopefully.
 
Its different with leather, and it can be oh so nice when ones back is sore.

My wife really wanted a heated steering wheel in her new car, but we couldn’t find one optioned that way. Next car, hopefully.

Yeah, seems very much material depended. Every car I have has cloth seats.

Now a heated steering wheel I can get behind. I'd trade heated seats for that feature.
 
My commute is only ten miles. Stays off, recirc, since the coolant barely gets up to temp by the time I get there.

I dress warmly, and use gloves when necessary, because the steering wheel will suck the heat right out me!

I’ve never been uncomfortable in my own car. I do use the seat warmers, though. Ya know, just to help warm the engine up faster with that extra load on the alter alternator, and totally not for my comfort!

On the really cold days the humidity is often low, so no issues with fogging. If there is fog, I obviously then the defogger on. For snow, I only turn the car on if If there’s ice I need help clearing; never for soft fluffy stuff that just brushes right off.
 
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