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Model S Plaid heating system sucks!!!

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When you say "refresh LR," do you mean the new model introduced along with the Plaid? Or the model before that with the new motors, new air suspension, improved audio, and so on, but with the round steering wheel? I get confused about various "refresh" versions. And either way, is it true that only the newest cars (2021 models with the Yoke) have the heat pumps vs. resistance heaters in the previous model S?

I mean the new model, introduced with the plaid. Palladium version.

In the forums, its seems like refresh is the term of choice, although I agree that Palladium is really the best descriptor.
 
If everyone used, "I have a 2021 Plaid or a 2020 Long Range Plus", etc. there would be no confusion. Until 2021, "refresh" always denoted 2018+ Model S cars. The 2021 is more than a refresh, in my opinion. Just say 2021!
Refresh was first used refer to the 2016.5+ version with the next front fascia, added interior console (versus the yacht floor). As I tried to state in my earlier post, the term refresh will always be ambiguous as it denotes an update from some baseline where the definition of the baseline or the timing/or level of update is clearly stated.
 
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i actually found this also to be true. i have the car at 79/80 and its blowing semi warm air... i have to have it on HI for it to blow significantly hotter air. the difference between 79/80 and HI shoulnd't be so drastic...
Anyone that has owned a homes with both a heat pump and a natural gas or electric resistive heating will likely understand that one of the negative characteristics of a heat pump is the discharge air temperature is not as hot as other type of heating systems. That results in many perceiving a home heated by a heat pump to not be as warm or more of a draft in the house as more air volume must be circulated for the same level of heating. Now when the back-up heat system kicks in for the heat pump, if you're standing near an air vent, you can typically feel a sudden warmth in the outlet air temp.

I expect this is what drives the perception of the big difference in setting the HVAC to "max" versus 79/80. I expect setting it to max forces the back-up resistive heating element to turn on even if the outside ambient temperatures would not require it to maintain the desired 79/80 degree interior cabin temp.

This is my hypothesis based upon my experience with other heat pump systems. I have no direct experience is a new Plaid or Palladium Model S to use that proposed nomenclature.
 
Now when the back-up heat system kicks in for the heat pump, if you're standing near an air vent, you can typically feel a sudden warmth in the outlet air temp.

One aspect of heat pumps is that they lose efficiency the colder the ambient temp is. For most home heat pumps, the tipping point is 30F. Once temps drop below 30F, the heat pump loses efficiency and has to work harder to pull more heat out of the air. For example, in single-digit temps, a heat pump will run constantly and will at best produce cool air. This is why they have backup heating elements.

That being said, the backup system is no joke. I know it uses a lot more energy to run as it's not all that different from what you see in a toaster, but it's like standing on the surface of the sun when it's on.

A good heat pump will be able to use a combination of normal/auxiliary (backup) systems to keep a stable temp.

Also of note - the backup systems can fail and stop functioning at which point you are left with just the primary heat pump and all of its caveats spelled out above.
 
Refresh was first used refer to the 2016.5+ version with the next front fascia, added interior console (versus the yacht floor). As I tried to state in my earlier post, the term refresh will always be ambiguous as it denotes an update from some baseline where the definition of the baseline or the timing/or level of update is clearly stated.
I think that one was referred to as “facelift”, not refresh.
 
I think that one was referred to as “facelift”, not refresh.
Nope. You can find numerous posts and threads referring to the model that was introduced in mid 2016 as the Model S refresh.

Here's one such thread with multiple entries from 2017 where it is clearly being referred to as refresh. I'm sure there are many others you can find, but this is one of the older ones I found doing a quick search.

 
Anyone that has owned a homes with both a heat pump and a natural gas or electric resistive heating will likely understand that one of the negative characteristics of a heat pump is the discharge air temperature is not as hot as other type of heating systems. That results in many perceiving a home heated by a heat pump to not be as warm or more of a draft in the house as more air volume must be circulated for the same level of heating. Now when the back-up heat system kicks in for the heat pump, if you're standing near an air vent, you can typically feel a sudden warmth in the outlet air temp.

I expect this is what drives the perception of the big difference in setting the HVAC to "max" versus 79/80. I expect setting it to max forces the back-up resistive heating element to turn on even if the outside ambient temperatures would not require it to maintain the desired 79/80 degree interior cabin temp.

This is my hypothesis based upon my experience with other heat pump systems. I have no direct experience is a new Plaid or Palladium Model S to use that proposed nomenclature.

Tesla's HVAC system is a lot more complex than your typical home heat pump with backup resistance heating.

If you're curious how it works, this three-part video series describes how the vehicle manages heat between the cabin, battery pack and atmosphere through its 12+ heating modes and 3+ cooling modes.



 
Anyone that has owned a homes with both a heat pump and a natural gas or electric resistive heating will likely understand that one of the negative characteristics of a heat pump is the discharge air temperature is not as hot as other type of heating systems. That results in many perceiving a home heated by a heat pump to not be as warm or more of a draft in the house as more air volume must be circulated for the same level of heating. Now when the back-up heat system kicks in for the heat pump, if you're standing near an air vent, you can typically feel a sudden warmth in the outlet air temp.

I expect this is what drives the perception of the big difference in setting the HVAC to "max" versus 79/80. I expect setting it to max forces the back-up resistive heating element to turn on even if the outside ambient temperatures would not require it to maintain the desired 79/80 degree interior cabin temp.

This is my hypothesis based upon my experience with other heat pump systems. I have no direct experience is a new Plaid or Palladium Model S to use that proposed nomenclature.

Great explanation, but no. I have a heatpump in my Model Y and it works great. Not so great in the Plaid.
 
My plaid heatpump works better than any car i have had gas,diesel or electric, even from a dead frozen 20* , i have good heat in 50-60 secs. Intense after 2 minites.

if you have the heat running for a long duration the outside heat exchanger might ice ip , the car has to defrost it and then return to producing heat , this wil explain the momentary loss of strong heat.

plaid heatpump system is an amazing engineering job and works fantastically.
 
One aspect of heat pumps is that they lose efficiency the colder the ambient temp is. For most home heat pumps, the tipping point is 30F. Once temps drop below 30F, the heat pump loses efficiency and has to work harder to pull more heat out of the air. For example, in single-digit temps, a heat pump will run constantly and will at best produce cool air. This is why they have backup heating elements.

That being said, the backup system is no joke. I know it uses a lot more energy to run as it's not all that different from what you see in a toaster, but it's like standing on the surface of the sun when it's on.

A good heat pump will be able to use a combination of normal/auxiliary (backup) systems to keep a stable temp.

Also of note - the backup systems can fail and stop functioning at which point you are left with just the primary heat pump and all of its caveats spelled out above.
So, just to be clear, the installation of heat pumps in Model S began with the Palladium models and not with the earlier Raven models?
And also, the Palladium system does include a backup resistance heater? Good to know, I was not aware of that, had only heard about the heat pump.
 
Tesla's HVAC system is a lot more complex than your typical home heat pump with backup resistance heating.

If you're curious how it works, this three-part video series describes how the vehicle manages heat between the cabin, battery pack and atmosphere through its 12+ heating modes and 3+ cooling modes.



Holy cow, that system is a lot more complex than I had imagined! These videos are quite informative (assuming they are accurate), but even though I am an engineer (now retired), I'd still have to study it a lot more truly to understand it.
The Octo-Valve is a clever and critical component. It reminds me (in a very general way) of an old Mercedes Benz first generation climate control system from decades ago that had a coolant valve system operated by a stepper motor. It worked great until it didn't. As I recall, the valve body would eventually leak and damage the stepper motor. There was a failure mode that could cause a fair amount of damage if not discovered soon enough (because it was leaking engine coolant that was used for the cabin heating portion of the functionality). I sure hope the Octo-Valve is well-built and there is leak detection in the system. It looks as if failures that cause leaks in the battery heating/cooling system as well as in the cabin HVAC loops.
 
My plaid heatpump works better than any car i have had gas,diesel or electric, even from a dead frozen 20* , i have good heat in 50-60 secs. Intense after 2 minites.

if you have the heat running for a long duration the outside heat exchanger might ice ip , the car has to defrost it and then return to producing heat , this wil explain the momentary loss of strong heat.

plaid heatpump system is an amazing engineering job and works fantastically.

The Tesla heat pump system does not have a refrigerant to air heat exchanger on the exterior of the car. As such, there is nothing to ice up and there are not the defrost cycles found in more traditional home heat pump systems.
 
I just picked up my Plaid yesterday. First impression is the car is amazing, but the heating system is awful. It’s inexcusable how bad the heating is for any car much less a car in this price range. It reminds me of a VW Beetle from the 1970s.
Actually, the old Beatles had amazing and super simple heating system. You could make a sauna inside while snowing outside :)