Any benefit setting digital thermostat to anything other than max heat in winter?

[Yzzim]

My boss has an 04 (??? whenever Ford came out with the new style) F-150. Right now it's -10ºF during the day and he's got his digital thermostat on his truck set at 79ºF. The thing goes up to 90ºF but he always has it set on 79ºF. Whenever we're in it, it takes FOREVER to warm up and he will never turn it higher.

Is there any benefit (gas, heater core wear/tear, etc) to running it at that temp? Does the heater core not heat up as much? Is it just mixing the hot air with the cold outside air to get it at the right temp?

Don't know why it bothers me, just doesn't seem wise if a person is "wasting" the hot air when it's fricken cold out.

 

[Ronstang]

It is not like it is costing any energy to turn the heat up. If he sets it to 79 all that happens is the heater blends cold air with hot from the heater core to achieve that temperature. The truck is still producing the excess heat the heater core carries away even if you don't utilize it. The only extra energy you could really be using would be that needed to drive the fan longer or at a higher speed but that is going to be pretty damned marginal at best. I am not sure if automatic climate controls in vehicles actually go to max until they reach the desired temp in the vehicle or they try to maintain that temp coming out of the register. I know on my Taurus SHO there is a little sensor in the dash that reads the temp of the cabin but any deeper than that I really don't know.

He isn't going to be wasting energy so tell him to set it to max to get the cabin warm and then reduce it to the desired temp once you get comfortable.

 

[Zenmervolt]

The digital thermostats will apply max heat until they approach the set temperature. As it begins closing in on the set temperature, say maybe 2-5 degrees away, it will begin to taper off to prevent overshooting the temperature.

Setting the thermostat to "MAX" will not make the car heat up faster, it will only keep the car from ever turning the heat off. The cabin will not heat up any faster by setting the control to max instead of leaving it at 79.

Ford's automatic digital thermostats also will not start the blower until the coolant has begun to heat up to the point where useful heat can be extracted. This can make it seem as though it is taking a while before the heat starts, but this still doesn't mean it will actually take longer to heat up.

ZV

 

[Yzzim]

Originally posted by: Ronstang
It is not like it is costing any energy to turn the heat up. If he sets it to 79 all that happens is the heater blends cold air with hot from the heater core to achieve that temperature. The truck is still producing the excess heat the heater core carries away even if you don't utilize it. The only extra energy you could really be using would be that needed to drive the fan longer or at a higher speed but that is going to be pretty damned marginal at best. I am not sure if automatic climate controls in vehicles actually go to max until they reach the desired temp in the vehicle or they try to maintain that temp coming out of the register. I know on my Taurus SHO there is a little sensor in the dash that reads the temp of the cabin but any deeper than that I really don't know.

He isn't going to be wasting energy so tell him to set it to max to get the cabin warm and then reduce it to the desired temp once you get comfortable.

Ok, that's what I thought.

So turning my manual dial to max heat (02 Ranger) would be the same as turning his digital dial to 90º (max). Basically no cold air is mixed with the heat coming off the heater core.

 

[DeviousTrap]

Originally posted by: Yzzim

Originally posted by: Ronstang
It is not like it is costing any energy to turn the heat up. If he sets it to 79 all that happens is the heater blends cold air with hot from the heater core to achieve that temperature. The truck is still producing the excess heat the heater core carries away even if you don't utilize it. The only extra energy you could really be using would be that needed to drive the fan longer or at a higher speed but that is going to be pretty damned marginal at best. I am not sure if automatic climate controls in vehicles actually go to max until they reach the desired temp in the vehicle or they try to maintain that temp coming out of the register. I know on my Taurus SHO there is a little sensor in the dash that reads the temp of the cabin but any deeper than that I really don't know.

He isn't going to be wasting energy so tell him to set it to max to get the cabin warm and then reduce it to the desired temp once you get comfortable.

Ok, that's what I thought.

So turning my manual dial to max heat (02 Ranger) would be the same as turning his digital dial to 90º (max). Basically no cold air is mixed with the heat coming off the heater core.

No, read ZV's post above yours. The heater will blow hot air, up until the cabin reaches the temperature that it set on thermometer. Only after the cabin has warmed up will the heater begin to blend hot and cold air to maintain that desired temperature.

 

[Ronstang]

Originally posted by: DeviousTrap

Originally posted by: Yzzim

Originally posted by: Ronstang
It is not like it is costing any energy to turn the heat up. If he sets it to 79 all that happens is the heater blends cold air with hot from the heater core to achieve that temperature. The truck is still producing the excess heat the heater core carries away even if you don't utilize it. The only extra energy you could really be using would be that needed to drive the fan longer or at a higher speed but that is going to be pretty damned marginal at best. I am not sure if automatic climate controls in vehicles actually go to max until they reach the desired temp in the vehicle or they try to maintain that temp coming out of the register. I know on my Taurus SHO there is a little sensor in the dash that reads the temp of the cabin but any deeper than that I really don't know.

He isn't going to be wasting energy so tell him to set it to max to get the cabin warm and then reduce it to the desired temp once you get comfortable.

Ok, that's what I thought.

So turning my manual dial to max heat (02 Ranger) would be the same as turning his digital dial to 90º (max). Basically no cold air is mixed with the heat coming off the heater core.

No, read ZV's post above yours. The heater will blow hot air, up until the cabin reaches the temperature that it set on thermometer. Only after the cabin has warmed up will the heater begin to blend hot and cold air to maintain that desired temperature.

That is only true with automatic climate control, not a manual heater. On some automatic climate control systems you can also turn off the auto function and choose a temp in which case you will not get max heat/cool to reach that temperature.

 

[LTC8K6]

The auto climate control is smart. It will do as ZV says.

It's a little hard to get used to if you have never dealt with it, but you soon realize that it works very well and it warms/cools the cabin as quickly as possible to your set temp.

The hardest thing to get used to is the fact that it waits until there is some heat in the coolant before it turns on.

 

[LS8]

Ford's EATC is a pretty good system. I have had three vehicles with it and I love it. Setting the t-stat at 90F is just to darn hot for me, I keep it at around 75F even in the winter. The system is smart enough to know how much to open the blend door (letting heat in from the heater core, a small radiator that draws heat from the engine, usually in the dash somewhere) and how much fan you need to get the cabin to the temperature you want.

 

[iamwiz82]

It's hard for people to understand that it isn't blowing out air at the temperature you set it to, it is trying to regulate the temperature tht you set it to, so it'll work as hard as it can to get to the that point and then just enough to hold it there.

 

[Savij]

Originally posted by: Zenmervolt
The digital thermostats will apply max heat until they approach the set temperature. As it begins closing in on the set temperature, say maybe 2-5 degrees away, it will begin to taper off to prevent overshooting the temperature.

Setting the thermostat to "MAX" will not make the car heat up faster, it will only keep the car from ever turning the heat off. The cabin will not heat up any faster by setting the control to max instead of leaving it at 79.

Ford's automatic digital thermostats also will not start the blower until the coolant has begun to heat up to the point where useful heat can be extracted. This can make it seem as though it is taking a while before the heat starts, but this still doesn't mean it will actually take longer to heat up.

ZV

That's exactly what my car does. I don't know how many times my friends will start messing with the dial when we get in my car. It's gotten to the point where I punch them in the arm if they put their hands near the temp dial.

 

[Zenmervolt]

Originally posted by: Ronstang

Originally posted by: DeviousTrap

Originally posted by: Yzzim

Originally posted by: Ronstang
It is not like it is costing any energy to turn the heat up. If he sets it to 79 all that happens is the heater blends cold air with hot from the heater core to achieve that temperature. The truck is still producing the excess heat the heater core carries away even if you don't utilize it. The only extra energy you could really be using would be that needed to drive the fan longer or at a higher speed but that is going to be pretty damned marginal at best. I am not sure if automatic climate controls in vehicles actually go to max until they reach the desired temp in the vehicle or they try to maintain that temp coming out of the register. I know on my Taurus SHO there is a little sensor in the dash that reads the temp of the cabin but any deeper than that I really don't know.

He isn't going to be wasting energy so tell him to set it to max to get the cabin warm and then reduce it to the desired temp once you get comfortable.

Ok, that's what I thought.

So turning my manual dial to max heat (02 Ranger) would be the same as turning his digital dial to 90º (max). Basically no cold air is mixed with the heat coming off the heater core.

No, read ZV's post above yours. The heater will blow hot air, up until the cabin reaches the temperature that it set on thermometer. Only after the cabin has warmed up will the heater begin to blend hot and cold air to maintain that desired temperature.

That is only true with automatic climate control, not a manual heater. On some automatic climate control systems you can also turn off the auto function and choose a temp in which case you will not get max heat/cool to reach that temperature.

The Ford system in my 1995 Lincoln behaved as I described. It is fully automatic as far as temperature control is concerned. You can override the fan speed or the vent settings, but it will always use max heat until the cabin reaches the set temperature even when the system is not in "full auto" mode.

ZV

 

[jagec]

Originally posted by: Zenmervolt

That is only true with automatic climate control, not a manual heater. On some automatic climate control systems you can also turn off the auto function and choose a temp in which case you will not get max heat/cool to reach that temperature.

The Ford system in my 1995 Lincoln behaved as I described. It is fully automatic as far as temperature control is concerned. You can override the fan speed or the vent settings, but it will always use max heat until the cabin reaches the set temperature even when the system is not in "full auto" mode.

ZV[/quote]

Yeah, if it gives you the ability to set a temperature, you are almost guaranteed that it will give you full heat until it starts to get close to that temperature.

You're only mixing air prior to cabin warm-up with systems that give you that classic layout with the red and blue bars.