If ANY of you guys have climate control set to automatic, the car itself will tell you when you can be the most efficient heating the car and the interior up. The climate control WAITS until the coolant has reached a temperature that will allow the blower enough heat to blow into the interior and slowly and continuously increases the coolant flow into the heater box. The fan then comes on slowly at first so as not to draw down too much too early and then picks up speed as the coolant temp rises. So, the valve is NOT opened initially and the fan does not run until coolant temp rises enough to make it worthwhile to use as a heat source for the cabin.
Initially you have to heat up both the cabin and the motor who are vying for the same heat. So unless you are real smart about your cars needs, you deal with your own first. Because the car is much smarter then I, I use the climate control on auto on the car that has it, and wait till a little till the needle moves on the other. If you experiment a little on cars without climate control, you might be able to find the best compromise using the temp gauge.
@dagosa You’re right. We have a high efficiency furnace with a variable DC motor in our house. When the furnace lights up, you can barely hear the fan, and it’s not drawing in cold outside air, unlike a car heater. As the heat exchanger warms up the fan goes faster gradually. Same with the cool down phase after the burner shuts off. The fan will still draw that residual heat out of the system for maximum effuciency.
This furnace has a Seasonal Efficiency rating of 98%. I’m not sure it will actually deliver that, but installing lowered the gas consumption from 240 million BTUs per year to only 137, proving that the old furnace without heat recovery condnser and using a pilot light was very inefficient indeed.
@Docnick
Like a lot of debates, there is no right or wrong answer as the answer is variable depending upon so many factors including outside temperature, the motor itself and the temp you have the cabin set to. It IS a case where artificial intel. is “smarter”…but only because we choose to give it more “sensors” then we could ever have. Besides, we have better things to do while the car is warming up…like text.
I would disagree. 20 degrees is not cold. Minus 20 is COLD.
It you live in Fla., 20 degrees is darn cold !
@dagosa and @Docknic are right. I have about a three mile drive to work these days. My cars with automatic temperature HVAC systems won’t even bother to to turn on the fan to circulate air through the heater core until I’ve gone the first mile or so on a 30ºF day. Ford’s spec is 112ºF. I don’t know what GM’s is, but it must be similar. If it’s a matter of comfort, which of course it is, don’t bother blowing cold air on your bod.
@Bing 20º is cold enough to need heat, therefor it’s cold. We don’t get to -20ºF very often, but agree it’s cold too.
I think we’ve lost something in comfort on today’s cars when first starting out in cold weather. Let’s bring back the Stewart Warner “South Wind” gasoline heaters They gave instant heat from the moment you turned them on regardless of the temperature of the coolant in the engine. I’ve ridden in cars with these heaters and there was instant warmth and instant defrosting of the windshield. In those good old days, a heater was an option. Many motorists chose purchase an after-market heater (either hot water or gasoline) rather than going with factory equipment.
The Prius uses an elec motor to turn the a/c compressor. So the gas motor does not need to run to cool the car. I do not know if there is an elec grid heat coil in the hvac for heating? Would not surprise me in the slightest if there was.
But @Tridaq modern HVAC equipment is so much more efficient, does not use gasoline that effects MPG, doesn’t need a separate exhaust, and will not asphyxiate the occupants when the heat exchanger gets a hole in it. I can remember the Southwind being somewhat tempermental in my dad’s old truck. Some days it was fine, and some days we were cold. There was no fresh air intake, although the truck was very drafty, or duct to defrost the windows.
I have also had gasoline heaters on a 1960 Corvair and a 1980 VW Vanagon. On the VW, I could start the heater without starting the engine, go back in the house, and come back to a warm van. It sounded like a muffled jet engine. There is a reason they were discontinued.
If miles per gallon is the holy grail, gasoline heaters for cars are out of the question, no matter how nice they are. VW introduced them on the beetle because so many Americans complained about the crappy heaters drawing heat from the engine fins. You always smelled exhaust fumes in the car as well. And the “defrosters” were anemic.
Well, I know that the Stewart Warner Southwind heaters were wasteful, but they sure warmed up the car quickly.
Home heating has also really improved over the last 25 years. I had a house built in 1989 and had a state of the art gas furnace installed. It exhausted through a PCV pipe, but pulled the combustion air from the garage where it was installed. A couple of years ago, I replaced the furnace with an even higher efficiency unit. This new unit pulls its combustion air from the outside. The garage where the furnace is installed in noticeably cooler and I am thinking about installing an electric heater when I work out there at my workbench. The good news is that our gas consumption is considerably lower.
@Triedaq Yes, an electric heater works great for the few times you work in your garage. I have one from Costco; it’s a large radiant one that directs heat to where you want it.
Our house furnace only draws a small amount of makeup air and the combustion air (separate intake) comes directly from outside.
@Docnick–Thanks for confirming that an electric heater in the garage works great. I had a 220 volt line installed in the garage when I had the house built in 1989 with the intent of installing an electric heater. However, the original furnace, which was in the garage, kept the garage warm enough so that I could work. However, the new furnace that is in the garage does not put much heat into the garage–the heat is sent into the house which is great for the 99% of the time I am not in the garage.
For a quick warm up in the car, I found that seat warmers can make you quite comfortable in about a minute or less while waiting for the engine coolant to come up to temp.
I’m with Keith on this one. The interior gets heated up faster with the temperature control turned all the way up and the fan on high.
@Tridaq Most plug-in heater work on 120 volts. They are normally limited to 1500 watts, but that’s a lot when it’s aimed at you directly. You may hook up an industrial strength one with 220 volts.
A few years back we stayed at a Bed and Breakfast in San Miguel de Allende in Mexico. This place is in the mountains and had neither heating or air conditioning. Our room had a plug-in oil filled radiator, which supplied enough overnight heat. That is the type I definitely do NOT recommend for your garage, because it tries to heat up the whole place rather than aim the heat at you, and takes too long to do so.
@Docnick–I put in a dedicated 220v circuit for an electric heater. I’ve seen a couple 220 volt heaters that will work. Since the wiring is there, I’ll substitute a 110 volt breaker if I go with a 110 volt hearer.
Your discussion of the oil filled radiator reminds me of an experience my son had when he rented a house for himself and his family. This was in eastern Tennessee. The landlord said the house had radiant electric heat. What he did was bring in three or four of those oil filled radiators. One night I received a telephone call from my son that there was a hot smell around the fuse panel. I lived 370 miles away and there was no way I could get down to help him. I thought really fast and told him disconnect all but one of those oil filled radiators, turn off the hot water heater and see if that would help. He called back an hour later and said he no longer had a hot smell around the fuse panel. I advised him to call the landlord the next morning and tell him something had to be done. An electrician was sent out and found that when the electric radiators were on, there was a 98 ampere draw on one leg of the fuse panel and only a 2 ampere draw on the other. The electrician balanced the load and the landlord provided a 220 volt heater to plug into the 220 volt socket in the living room that powered a through the wall air conditioner and they got through the rest of the winter. I’ve never liked the oil filled radiators. My parents had one and on the highest heat setting, the cord and plug became very hot. I advised them never to use the high heat. Ultimately, there was a recall and my parents were sent a kit to replace the cord and thermostat.
At any rate, I definitely won’t use an oil filled radiator for heat. I won’t do anything until next summer as I still have boxes of books and other items that I brought home from my office when I retired two and a half years ago. I bring a box to my den to sort through for what I want to keep and what to give away or throw away. This will take me until summer when I really want to fix up the garage. The best I can do right now is get both cars in the garage.