Heater on/off Button?

[Dborn]

a dehumidifier mode is what is required. Likely, though, it will use both heating and cooling modes to achieve your set temperature depending on ambient conditions. At least, that is what happens with conventional air conditioners.

 

[mknox]

There is no heat pump in the Model S, only A/C. The heating in the cabin is exclusively from a 6-7kW PTC resistance heater. There is also no path for using waste heat from the powertrain or electronics to heat the cabin. (Though it can heat the battery).

I still need to get back to Tesla on this, but was very clearly told when I specifically asked that the electric heater that heats the battery (via the liquid coolant) can also extract heat from the battery, motor and inverter and use it to supplement cabin heat via a "heater core" similar to what an ICE would use on its cooling system. No heat pump, and this would have nothing to do with the cooling system. The way the system works and the way the energy draw tapers as the car warms up sure seems to support this over 3 very cold winters I've been through. My car is extremely frugal with its heating energy consumption compared to several Leaf owners I know.

 

[Ingineer]

I still need to get back to Tesla on this, but was very clearly told when I specifically asked that the electric heater that heats the battery (via the liquid coolant) can also extract heat from the battery, motor and inverter and use it to supplement cabin heat via a "heater core" similar to what an ICE would use on its cooling system. No heat pump, and this would have nothing to do with the cooling system. The way the system works and the way the energy draw tapers as the car warms up sure seems to support this over 3 very cold winters I've been through. My car is extremely frugal with its heating energy consumption compared to several Leaf owners I know.

Whomever "clearly told" you this is mistaken. The hardware simply isn't there to do what you claim, it doesn't exist, period.

These are facts of which I am 100% sure of:
1. There is an electric battery coolant heater. This can use high-voltage to heat the pack via way of the glycol loop.
2. There is an electric PTC cabin heater which uses high-voltage to directly heat the air in the cabin.
3. There is a glycol to R-134A heat exchanger that lets the A/C compressor also cool the battery glycol loop. This is optionally selectable by valving and a refrigerant solenoid.
4. There is a cabin R-134A evaporator that can cool the cabin air. This too can be shut off by solenoid if only glycol cooling is wanted by the system.
5. There are no other lines into the cabin. The glycol loop does not enter it, and it's easy to see this with a casual look under the frunk cowling. This would be needed for what you claim and it simply doesn't exist.

 

[mknox]

Whomever "clearly told" you this is mistaken. The hardware simply isn't there to do what you claim, it doesn't exist, period.

This is disappointing to hear (i.e. that I was mislead), because I spent considerable time back in 2011/2012 discussing this with Tesla representatives when they came to my area to show the Alpha car and later the Beta prototype. Living in an area with very cold winters, it was high on my priority list to understand. A small consolation, I suppose, is that it seems to act as if it's harvesting heat because after about 30 minutes in well below freezing temps, I can drive for hours at summer-like Wh/mi values, even if I stop for a coffee and the cabin cools right down. I only see the huge power numbers upon initial startup if the whole car is completely cold-soaked. Short trips in the winter are brutal on range, however.

 

[Ingineer]

This is disappointing to hear (i.e. that I was mislead), because I spent considerable time back in 2011/2012 discussing this with Tesla representatives when they came to my area to show the Alpha car and later the Beta prototype. Living in an area with very cold winters, it was high on my priority list to understand. A small consolation, I suppose, is that it seems to act as if it's harvesting heat because after about 30 minutes in well below freezing temps, I can drive for hours at summer-like Wh/mi values, even if I stop for a coffee and the cabin cools right down. I only see the huge power numbers upon initial startup if the whole car is completely cold-soaked. Short trips in the winter are brutal on range, however.

It's possible that the Alpha cars might have had a different system, but the ones we drive are as I stated.

Keep in mind, that the battery has a lot of thermal mass, so if it's being heated in the winter, then it would take a long time to cool off. The act of driving (or charging) may be enough to keep the pack warm once it's up to temp. The pack was way more thermal mass than the cabin, so it's probably this that's eating the most energy.

Ideally you schedule your charge so it just finishes before you are ready to depart in the morning, and you turn on your HVAC about 30 mins before you leave. This way you use less pack energy heating the pack/cabin and you'll benefit from longer range.

 

[omarsultan]

Add me to the list of folks that would like a simple vent button that brings in outside air unchanged--here in NorCal, much of the year, I would be happy if I could simply pipe in the outside air, leaving the car the discretion to dehumidify as it thought appropriate to reduce the risk of mushrooms sprouting in inconvenient spots.

 

[mknox]

It's possible that the Alpha cars might have had a different system, but the ones we drive are as I stated.

Keep in mind, that the battery has a lot of thermal mass, so if it's being heated in the winter, then it would take a long time to cool off. The act of driving (or charging) may be enough to keep the pack warm once it's up to temp. The pack was way more thermal mass than the cabin, so it's probably this that's eating the most energy.

Ideally you schedule your charge so it just finishes before you are ready to depart in the morning, and you turn on your HVAC about 30 mins before you leave. This way you use less pack energy heating the pack/cabin and you'll benefit from longer range.

Yeah, the thermal mass of the battery makes sense in my scenario of park for a few minutes, continue and see no huge energy draw. I went back to my notes from when I was researching this and unfortunately didn't jot down the names of the individuals I spoke to. It's possible, but I feel highly unlikely, that early cars and/or cars destined for "cold climates" have a different setup.

Yes, I do schedule the charge to complete just before I leave, and usually turn on the HVAC via the mobile app just before I jump in the shower in the morning (in winter).

 

[dhanson865]

Sorry. I might not have been clear enough. I'm referring to the vent selection icon:

Assuming the vent selection is left on "Auto", The arrow will point to the "head" when A/C is on. The arrow will point to the "foot" when heater is on. If both arrows are displayed, then it's probably blending both A/C and heat.

You can try this out by adjusting the temp 1-degree at a time up and down and you should see this behavior.

I'd be nice if the arrows changed color

white for fan only (unheated, uncooled air)

blue for AC (dark blue when compressor is on, light blue when selected but not currently drawing extra power)

red for heat (dark red when heat is on, light red when selected but not currently drawing extra power)

blue top and red bottom for mixed (or maybe a blue line and red triangle?)

 

[W0QR]

Blowing Hot and Cold | Tesla Motors

 

[Jaff]

Like this idea of colour coding...you should submit it to Tesla for consideration!

I'd be nice if the arrows changed color

white for fan only (unheated, uncooled air)

blue for AC (dark blue when compressor is on, light blue when selected but not currently drawing extra power)

red for heat (dark red when heat is on, light red when selected but not currently drawing extra power)

blue top and red bottom for mixed (or maybe a blue line and red triangle?)

 

[supratachophobia]

We need a heater on/off button, similar to the AC on/off. I picked-up my car in May so I haven't spent a winter in it yet. The other day, it was 70-degrees (F) but humid in the early evening. I turned the AC on to take the humidity edge off, but with the temp set at 70-degrees, I felt a little chilly so I turned it up to 73. Doing that caused the heater to turn-on. I know this because I could smell it. The heater had never been used so it had a burning type of smell. As soon as it turned it back down to 70, the smell went away.

Why would the heat turn-on when the AC is on and it is 70-degrees outside? If that's a general preference, okay, fine, but I'd like to be able to override that. I just wanted to minimize the AC, not turn the heat on.

If there were an on/off/auto button for heat, that would be great. Auto for the masses and on/off for someone like me who wants to be able to control it.

If it were an ICE, I wouldn't care, but since the heat uses a lot of electricity from the battery, I don't want it turning-on without my knowledge. Once the smell burns-off, I won't even know the heat is running....which brings up another request, there should be an indicator on the screen telling you when the heater is running. Even if an on/off is not possible for some reason, at least the indicator would warn you to lower the temp until it turns off.

Am I the only one who cares about this? I searched but couldn't find any discussions about it.

We have this suggestion currently entered and up for votes over here: Vote on software features/bugs to fix in 7.1 and beyond

Please vote and let Tesla know what you want.

 

[JenniferQ]

We have this suggestion currently entered and up for votes over here: Vote on software features/bugs to fix in 7.1 and beyond

Please vote and let Tesla know what you want.

I'm not sure this is the same issue, but sometimes I want just the fan on and not the compressor, so I turn the a/c off but keep the fan on. It then shows "custom" instead of "auto" in the ac dialogue. So it can blow the 68-70 degree outside air through but doesn't run the compressor. That won't help with humidity issues though.

 

[gavine]

I'm not sure this is the same issue, but sometimes I want just the fan on and not the compressor, so I turn the a/c off but keep the fan on. It then shows "custom" instead of "auto" in the ac dialogue. So it can blow the 68-70 degree outside air through but doesn't run the compressor. That won't help with humidity issues though.

And, depending on the outside temperature, it might engage the heater which is why a heater button is needed. Why is there an AC on/off, but not a heater on/off? Back to the original post, in an ICE, the heat is "free" so no need to turn it on/off but on an EV, heat is "expensive" so you should be able to disengage it.

 

[garygid]

If the lowest temperature settings included a setting called "OFF",
used to keep the heater Off, that might be sufficidnt, right?

 

[dhanson865]

If the lowest temperature settings included a setting called "OFF",
used to keep the heater Off, that might be sufficient, right?

That'd be great. On some cars they drop to "Max Cool" after the lowest temp. It'd be nice if the next stop was "OFF".

60F
Max Cool
Off

or

60F
Off

either way you'd have control over the heat/air by turning it to the extreme of the temp range plus one or two notches to get to OFF.

 

[dhanson865]

Whomever "clearly told" you this is mistaken. The hardware simply isn't there to do what you claim, it doesn't exist, period.

These are facts of which I am 100% sure of:
1. There is an electric battery coolant heater. This can use high-voltage to heat the pack via way of the glycol loop.
2. There is an electric PTC cabin heater which uses high-voltage to directly heat the air in the cabin.
3. There is a glycol to R-134A heat exchanger that lets the A/C compressor also cool the battery glycol loop. This is optionally selectable by valving and a refrigerant solenoid.
4. There is a cabin R-134A evaporator that can cool the cabin air. This too can be shut off by solenoid if only glycol cooling is wanted by the system.
5. There are no other lines into the cabin. The glycol loop does not enter it, and it's easy to see this with a casual look under the frunk cowling. This would be needed for what you claim and it simply doesn't exist.

I trust your word. I just thought you might want to weigh in on this post.

Tesla Patent Outlines Sensible Approach to Cabin Heating

 

[Ingineer]

Just because they filed a patent doesn't mean they use it currently. (or ever)

I can assure you that the Model S isn't set up as described in the article.

Here is a picture from the diagnostic menu on the Model S showing the schematic of the actual system:

While there is no way to use drivetrain waste heat to warm the cabin, they can use it to warm the pack when it's cold. The only source of heat for the cabin is the PTC heater. (besides the seat heaters and the people themselves)

The Tesla drivetrain is so efficient there isn't much waste heat anyway, and definitely not enough to heat the cabin comfortably anyway.

 

[dhanson865]

Just because they filed a patent doesn't mean they use it currently. (or ever)

I can assure you that the Model S isn't set up as described in the article.

agreed I just thought it'd save a few steps in the loop/cycle if you refuted it directly now vs me posting there and someone asking you refute it later after even more confusion had time to sow.

 

[lucy]

ok, guess I'm missing something...
I was dinking around with the fan speeds and the temps, trying to get the fan off and just use the seat and steering wheel heaters (best thing evah!!!) in these relatively mild fall days. Could get the temp to "LO" and fan to "1", not satisfactory.

Then, purely by accident, I must have double touched the "climate" icon, and it went grey and the fan shut off. I am calling this good. Seat/steering wheel heaters remained toasty. Good enough until it gets really cold (below freezing). Is this a new feature? Seems like OFF to me...

 

[kirkbauer]

Perhaps a dumb question but how do you vent fresh air without the fan, a/c, or heat on?