GX4h heater

[jazzboy]

Hi all. Sorry if this has been answered elsewhere, although I can't find the actual answer on searching.

Is the electric heater in the GX4h a heat pump type, or a resistive element type? One would have thought that having already got an air conditioner installed to provide chilled air in Summer, they would have made it reversable (like all inbuilt domestic or industrial aircon units are) to provide heating in Winter when the ICE is not running. A heat pump type heater would surely use less power than an element type.

Thanks in advance.

Peter

PS I'm getting my first 2016 Outlander PHEV next week!

 

[elm70]

Electric heater in the PHEV is inefficient in the worst possible way.

Electric heater sucks almost 4kw power, and does increase only 7 deg after 10 minutes of running.

This 10 USD heater possibly does a better job with 150W only : http://www.ebay.com/itm/2-in-1-Car-Portable-Ceramic-Heating-Cooling-Heater-Fan-Defroster-Demister-DC-12V-/361498844398

 

[Trex]

Electric heater in the PHEV is inefficient in the worst possible way.

Electric heater sucks almost 4kw power, and does increase only 7 deg after 10 minutes of running.

This 10 USD heater possibly does a better job with 150W only : http://www.ebay.com/itm/2-in-1-Car-Portable-Ceramic-Heating-Cooling-Heater-Fan-Defroster-Demister-DC-12V-/361498844398

And you sir must be one of the biggest whingers I have seen on this forum and this place has a few. :mrgreen: Just read some of your previous comments.

You should sell the PHEV to make yourself happy. Whinging all the time is not good for your health IMHO.

The heater worked well for me in the snow on top of the Great Dividing Range here last year (about -10 C outside not including wind chill). No I am not including the petrol motor heater.

And pre heating the cabin was a godsend. The PHEV is a great piece of engineering IMO. But obviously not in yours. You should sell it and move on and be happy.

 

[Trex]

Hi all. Sorry if this has been answered elsewhere, although I can't find the actual answer on searching.

Is the electric heater in the GX4h a heat pump type, or a resistive element type? One would have thought that having already got an air conditioner installed to provide chilled air in Summer, they would have made it reversable (like all inbuilt domestic or industrial aircon units are) to provide heating in Winter when the ICE is not running. A heat pump type heater would surely use less power than an element type.

Thanks in advance.

Peter

PS I'm getting my first 2016 Outlander PHEV next week!

As far as I know it is resistive which yes are less efficient than a heat pump.

But I would think heat pumps or reverse cycle A/Cs are also more expensive. Maybe reverse cycle A/Cs are too big of an item to easily fit inside of cars yet.

Do any hybrid, or otherwise, cars have reverse cycle A/Cs yet? :? A quick search does not show me any. But I may have missed it.

Some pure electric vehicles have a separate heat pump I think, BMW i3 comes to mind (but not the REX version I think from memory), but that vehicle is quite a bit more expensive here in Australia. As a pure electric vehicle they need to be more efficient if possible or they may not make it home. :lol: Remember the PHEV has a petrol motor as well.

Hope you love your new PHEV as much as I love mine.

 

[anko]

New Chevy Bolt EV / Open Ampera e does not have a heat pump. And this is, as the name gives away, a pure EV.

 

[Trex]

New Chevy Bolt EV / Open Ampera e does not have a heat pump. And this is, as the name gives away, a pure EV.

Yes and that would be why I used "Some pure electric vehicles" and "if possible" in my quote above.

Yes.I think the heat pumps must be still more expensive and or maybe less reliable (more moving parts) because they are still fairly scarce are they not?

 

[elm70]

I would like to see a heater pump work when is temperature is -5 or -10

There is no special need for heat up a car cabin ... no reason for go "exotic"

Unfortunately on the PHEV the electric heat is a half hack ... it does warm the engine coolant .. which cause a big waste of energy if the aim is to heat the cabin .. but it does help for warm up the engine before start it (but I'm not sure this is really used for this aim)

Anyhow ... I think I'm very objective to say that consume 4kw power for 10min and get only +7 deg in the cabin is not really an efficient way to heat the car ... plus all the other errant stuff associated to the PHEV cabin heating that can cause unwanted ICE start.

 

[Steepndeep]

I actually think the current electrical heater in the PHEV is quite good, (apart from the ICE start implementation but that is another story).

First you must consider that the implementation is made to heat the car while driving at speed, more on that later.

Checking DEFA cabin heater they start at 1400 Watts so I think the suggested 150W heater will not work at all.

Then you should also understand the huge difference between heating the car at standstill with no passengers in it vs. at highway speed with passengers in cabin. The car has single pane windows and basically no thermal insulation so you cannot allow the humidity level to be higher in the car than outside. Activate Ventilation Circulation when subzero outside and see what happens Having a cabin heater circulate air in car while blasting outside air temperatured air on windscreen will not work. Hence you must heat incoming are before it hits the cabin compartment. And then it makes sense (to me at least) to have one heatexchanger only (water coolant to air) instead of adding one more on top (electricity thermal to air). You will then get the additional effect on preheating the ICE coolant before the ICE starts (provided you preheat). So all-in-all I think it is quite good.

What would improve the system enormously is to add a heatexchanger between outgoing and incoming air but I think that may be difficult. Incoming air in front, outgoing in back, excessive plumbing, must consider humidity in cabin, cost of heat exchanger and risk of icing in it at low temperatures. Maybe here is a field for some research

 

[Kesto]

I think 4hs has heat pump at 2016 model. It is in the book. It is very effective and I found it quicker than my previous deisel cars. I also have 150 w heater which I bought for my previous 7 seater . Useless and noisy

 

[Muddywheels]

I also find heater in my 4h MY16 very effective - better than previous Range Rover Sports :mrgreen:

 

[Steepndeep]

Exactly what is described in which book? That the car has an electric heater? Or that it has an electrically driven heater of a specific design (resistor, compressor driven heat pump or other??) I have a 2016 and I am very sure (>90%) that it has a resistor based electrical heater.

As for "efficiency" I agree that it heats the cabin QUICKER than my previous diesel car after cold start. But that does not make it more efficient per se, only more convenient

 

[anko]

Unfortunately on the PHEV the electric heat is a half hack ... it does warm the engine coolant .. which cause a big waste of energy if the aim is to heat the cabin .. but it does help for warm up the engine before start it

This is not correct. The heater does NOT warm up the ICE. Only the reverse is true. Again, get your facts straight ;-)

 

[elm70]

Unfortunately on the PHEV the electric heat is a half hack ... it does warm the engine coolant .. which cause a big waste of energy if the aim is to heat the cabin .. but it does help for warm up the engine before start it

This is not correct. The heater does NOT warm up the ICE. Only the reverse is true. Again, get your facts straight ;-)

Am I wrong?

Isn't the electric heater working over the engine coolant ?

Even if the coolant circulation pump it is not activated in this "condition", it is by "physic' that ICE will get warmed up, since liquid will start to flow even without pump if some part of it is getting warmed up

 

[anko]

There is a thermostatic valve separating the ICE circuit from the heater circuit which only opens up when the coolant in the ICE circuit is at least 70 deg C and the ICE is running.

This valve has been discussed so many times. Last time was less than a day ago, in another topic on Heater behaviour ...

 

[elm70]

Ok ... there are some pictures on page 13x of the "PHEV Outlander Technical Highlights" ... not clear where is the location of the HVAC / heater Core ... but I suspect some of the pipes or elements are exposed to the external "elements" under the hood

Just trying to figure it out how is possible that 4kw heating power is so inefficient.

I'm using 8kw for heat a full floor of my house ... my radiators get warm to touch after 2 minutes from start, and we speak of tons of circulating water and multiple big radiators ...

4kw is what tesla is also using for heating, and it is consider more then enough ... but .. clearly not for mitsubishi or not for the PHEV design since this system is used only if delta temperature is less then 10 degrees.

Anyhow ... whatever is behind .. 4kw for 10min (0.67kwh energy) that make only +7 deg in the cabin it sounds a poor performance

Per my "maths" with 0.67kwh it is possible to increase the temperature by 7 deg of over 80L of water ... so ... the PHEV heating efficiency is looking very poor to me ..

 

[anko]

Have you felt / measured the temperature of the water in the heater circuit after 10 minutes of operation? If not, what are you comparing to what? I think you cannot compare heating up water in a kettle (or radiator) to heating up a cabin via air in the cabin, just like that.

 

[jaapv]

And without knowing the volume of the cabin, nor the heat loss.

 

[elm70]

Have you felt / measured the temperature of the water in the heater circuit after 10 minutes of operation? If not, what are you comparing to what? I think you cannot compare heating up water in a kettle (or radiator) to heating up a cabin via air in the cabin, just like that.

I gave a physic relation between energy and temperature increase .. 0.67kwh = 7deg x 80L .. or 70deg for 8L .. or 560deg for 1L

Air compared to water does need way less energy for increase the temperature .. the 2M3 of PHEV cabin is possibly equivalent or less then 1 litre of water ... ideally without energy waste the cabin of the PHEv with 0.67kwh can be bring over 500deg

Clearly ... there are energy dissipation in a car.

Question is how much "wasted" energy is happening ... and based on the "visible results" it is quite much.

Main reference is the 4kw heating system used on tesla ... that is for sure over dimension by design .. while the PHEV 4kw since it 'wants" the help from ICE... it is clearly "under-dimension"

Anyhow ... I find interesting to notice that, that my house have been designed for be heated up per floor with 8kw .. and 4kw are not enough for the PHEV :shock: .. both are electric heating with water fluid involved

OK .. you can always say I got a lemon PHEV ... so if your PHEV manage better then 7deg temperature increase after 10min of pre heating .. let me know

 

[anko]

I was not talking about heating up air. I was talking about heating up a cabin ... via air.

 

[Dusz]

Houses have a lot more thermal insulation in them than a car. If you have ever slept in a car you would find that even in summer it is very cold. Heat loss depends on the temperature difference between inside and outside. I would imagine that in Poland the outside temperatures are quite low at the moment so given a constant energy input the temperature inside will be lower.