Heater on/off Button?

[Great Dane]

I Have an P85 and completely agree with gavine
sometimes in the morning you need just a little ac
so like a thermostat in the house you should be able to set it
at 76 degrees so it would cycle the compressor when needed
and would also increase your range by not having the compressor on all
the time
I actually build a electric cycler for my ice
Because it would keep the compressor running
when you adjusted the stupid air duct temp control
that would just mix in hot air from the engine
it worked perfect
12 seconds on 30 seconds off
or 12 seconds on 60 seconds off
giving nice temp control and improving millage
and for an electric car this is very important
its actually worse because the compressor will run
and the strips will kick in and sucking down your battery
go ahead plug your car in don't set to charge. turn on climate and
and watch amp draw from outlet on your charge display
we need a software switch for heat or ac !

 

[gavine]

Thanks guys. I was starting to think I was crazy for asking for this based on the first round of replies. I was just figuring they weren't getting it. I'm so glad you agree. I feel much better now.

In the end, if Tesla won't give us an on/off for the heater, at least give an indicator on the display saying when the heat is running. This way, I can adjust the temperature down until it shuts off. That would be good enough for me. If it weren't for the smell, I would never know it was on and that's wrong. As was mentioned earlier, the heat in a gas-powered car is just there but with an electric car, a lot of power is being used for it when I don't necessarily want or need it.

Also, the suggestions about putting the temp on low with the AC off and adjusting the fan manually is okay, but not if I need the AC for humidity. When you put temp on LO with the AC on, the AC compressor runs at full-blast and freezes you out, especially at night. I want to be able to run the AC compressor at it's lowest setting (just for humidity) and not blend heat with it.

 

[rlang59]

Thanks guys. I was starting to think I was crazy for asking for this based on the first round of replies. I was just figuring they weren't getting it. I'm so glad you agree. I feel much better now.

In the end, if Tesla won't give us an on/off for the heater, at least give an indicator on the display saying when the heat is running. This way, I can adjust the temperature down until it shuts off. That would be good enough for me. If it weren't for the smell, I would never know it was on and that's wrong. As was mentioned earlier, the heat in a gas-powered car is just there but with an electric car, a lot of power is being used for it when I don't necessarily want or need it.

Also, the suggestions about putting the temp on low with the AC off and adjusting the fan manually is okay, but not if I need the AC for humidity. When you put temp on LO with the AC on, the AC compressor runs at full-blast and freezes you out, especially at night. I want to be able to run the AC compressor at it's lowest setting (just for humidity) and not blend heat with it.

This is only the case when the resistive heater is going when the car has not gotten up to temperature yet. After that the heat from the drive train is used.

 

[scaesare]

Also, the suggestions about putting the temp on low with the AC off and adjusting the fan manually is okay, but not if I need the AC for humidity. When you put temp on LO with the AC on, the AC compressor runs at full-blast and freezes you out, especially at night. I want to be able to run the AC compressor at it's lowest setting (just for humidity) and not blend heat with it.

Ah, good point. Makes sense.

 

[trils0n]

In the end, if Tesla won't give us an on/off for the heater, at least give an indicator on the display saying when the heat is running.

I live in California, so I don't use the heat much, but I think I remember from last winter that the border around the temperature numbers at the bottom of the dash turns red when then heater is on.

 

[ruby110]

I agree with gavine. I wanted fresh air when the outside temp was 60 and "lo" is 63, I think. I was concerned that I would get heat and I didn't want the energy loss. I hope the resistive heat isn't used much but then I don't understand why Tesla says to use the seat warmers to reduce heater usage.

BTW, I asked my DS about how to turn off the heat and he didn't know so he contacted the service staff. They haven't responded and it's been days.

 

[ken830]

In the end, if Tesla won't give us an on/off for the heater, at least give an indicator on the display saying when the heat is running.

Did you not see this? Or is this not good enough?

If you leave the vent selection (face/feet) in Auto mode, the icon will tell you when the heater kicks on. A/C will be on when blowing at the face-only. Heater is on when blowing at the feet only. Both are on (I'm guessing) when both vents are selected.

 

[brkaus]

Not really for/against... But a standard house thermostat typically has off/heat/cool/auto and sometimes fan as options. That to me would be better than a special heat on/off button.

 

[gavine]

Did you not see this? Or is this not good enough?

I tried it, but I didn't see any indicator for the heater. Where is it displayed and what does it look like?

 

[AmpedRealtor]

I agree with gavine. I wanted fresh air when the outside temp was 60 and "lo" is 63, I think. I was concerned that I would get heat and I didn't want the energy loss. I hope the resistive heat isn't used much but then I don't understand why Tesla says to use the seat warmers to reduce heater usage.

LO is low, not 63. When set to LO and A/C off, the climate control system is off with the exception of the fan and is delivering air untouched.

 

[scaesare]

LO is low, not 63. When set to LO and A/C off, the climate control system is off with the exception of the fan and is delivering air untouched.

Not if you select the windshield vents.

 

[jerry33]

Not if you select the windshield vents.

Isn't that the same with every modern car? If you select the defrost vents, a/c kicks on to reduce fogging.

 

[rlang59]

Isn't that the same with every modern car? If you select the defrost vents, a/c kicks on to reduce fogging.

All of the ones I've been in recently have does this.

 

[ken830]

I tried it, but I didn't see any indicator for the heater. Where is it displayed and what does it look like?

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.

 

[ThosEM]

Perhaps the actual need is for a dehumidifier mode? Then the heat pump would run in AC mode, but the waste heat would be sent to the cabin instead of to the outside, more than nullifying the air cooling effect but retaining the extraction of water from the air. The amount of heat delivered would be quite small, just as it is for a dehumidifier operated in a home. In ICE cars this is often done in the most wasteful way possible, by using waste heat from the engine to nullify the air conditioning and warm the cabin slightly even when AC is running.

 

[gavine]

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 get it now. Thanks for clarifying. This will do for now but I still hope Tesla addresses this concern in a future update release.

 

[ElSupreme]

Perhaps the actual need is for a dehumidifier mode? Then the heat pump would run in AC mode, but the waste heat would be sent to the cabin instead of to the outside, more than nullifying the air cooling effect but retaining the extraction of water from the air. The amount of heat delivered would be quite small, just as it is for a dehumidifier operated in a home. In ICE cars this is often done in the most wasteful way possible, by using waste heat from the engine to nullify the air conditioning and warm the cabin slightly even when AC is running.

I am not 100% familiar with the HVAC setup the Model S has. I am not even 100% sure it is using the AC as a heat pump, as I have seen no proof of this (I have not been looking for it either).

But using the AC as a dehumidifier requires a large portion of the wast heat to be recovered. And you need physical heat exchanger routing in place to achieve this. Or some other waste heat stream to re-heat the air. Maybe I'll dig into my car and see how the HVAC is setup, or someone else can chime in on the details.

 

[ruby110]

LO is low, not 63. When set to LO and A/C off, the climate control system is off with the exception of the fan and is delivering air untouched.

@AR: Thanks for the clarification. Untouched air is what I was looking for.

 

[Great Dane]

Thank you so much Ken830 for posting the picture that was exactly what we needed
so now we can at least see what is going on with the HVAC system in the car
always learning more about the car. Heat 76 off 77 on in my case
depending on temps outside of course.
ElSupreme according to me it is straight heat strips, for heat not a heat pump
I bet next generation might do it because a heat pump is so much more efficient

 

[ThosEM]

I am not 100% familiar with the HVAC setup the Model S has. I am not even 100% sure it is using the AC as a heat pump, as I have seen no proof of this (I have not been looking for it either).

But using the AC as a dehumidifier requires a large portion of the wast heat to be recovered. And you need physical heat exchanger routing in place to achieve this. Or some other waste heat stream to re-heat the air. Maybe I'll dig into my car and see how the HVAC is setup, or someone else can chime in on the details.

I'm certain the Model S uses a reversible heat pump for both AC and heat, with a resistance heater as an auxiliary to the heat pump when it is below freezing outside. So it has heat exchangers for both the interior air and the exterior air, just like a residential heat pump system.

Having just bought/installed a couple of dehumidifiers, I realized that they are nothing but heat pumps for which the heat exchanger is inside the room being conditioned, basically a refrigerator that just cools air momentarily, long enough to condense out water, then rewarms the cooled air with the same heat it pumped out of it, plus the motor heat, and sends it back to the room. Operating either a refrigerator or a dehumidifier produces a net energy input to the room because there is no other place to which to pump the heat. In AC/heat mode, the heat gets pumped from inside/outside the car to outside/inside the car. So a dehumidification mode would just require that the exterior heat exchanger be switched to interior air flow.