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I have a Tekna 66 plate Leaf. In the past, when I want heat from the fan blower, I normally set my climate to around 20 degrees. This feels quite comfortable and on rare occasions I do want more heat, then I have never had to go above 21 degrees.

Recently I have noticed a strange heating issue. The temperature has dropped low enough a few times recently that I've put on the heat, but setting the temperature to 20 degrees blows cold air. It doesn't feel like air conditioned cold air but rather the cold air from outside. If I crank up the heat setting to 25 degrees then I start to feel a little heat but it's only when I set the temperature to 27 or 28 degrees do I get the kind of temperature that I used to get when setting at 20 degrees. Clearly the car is able to output heat but it's like the heat control calibration is off.

This is the first time I've had to use the heat for a while. We had many months of warm temperature so last time I used heat was probably February to April time (not sure exactly).

I don't think this is an issue or in anyway related but during the warm periods, I noticed the car creating a puddle of water after it had been driven. I'm pretty sure this is normal when you're using the air conditioning but thought I'd mention in case there was some obscure link with the heating issue.

Any thoughts?
 

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Does the air conditioning seem to be as effective as it should be if you turn it down to 16 and set the fans to high on the face vents ?

Is the outside temperature reading on the dash accurate ? Do you have Leafspy by any chance ?

The heater uses the PTC heater, the heat pump, or both together depending on conditions. The PTC heater is fast to heat and can produce really hot air, the heat pump is slow to heat up and can only produce moderately warm air, but not truly "hot" air.

When you first turn the heater on and the car is cold it will bring on both the PTC heater and the heat pump in heating mode at the same time. The PTC heater gives that initial quick warm up and blast of really hot air to get the car up to temperature, as it warms up the PTC heater dials back and at some point goes off, leaving only the heat pump producing enough heat to keep the cabin at a comfortable temperature.

This can be seen on Leafspy as it measures the power drawn by the PTC heater and Heat pump separately.

What you describe sounds a bit like the heat pump is not working in heating mode. The PTC heater will only come on initially for a short time, or stay on if there is a very high demand, but for low demands it will rely on the heat pump. So if that's not working then if you are within a few degrees of the set point you'll be getting no heat and would only get heat when you turn it up really high which would be enough to bring the PTC heater back on again.

Another possibility is a fault with one of the temperature sensors, unfortunately LeafSpy does not report the cabin temperature sensor or vent temperature sensors, it only reports the same outside temperature you can already see on the dashboard.

Another test you could try is to plug the car in to your charger, sit in the car with the car off and turn on the remote climate control with your phone. Remote climate control does not use the heat pump for heating, it relies entirely on the PTC heater. So if the car produces warm air in remote climate mode you know the PTC heater is working. You can verify the heat pump is not being used in remote climate mode by the radiator fans at the front not coming on.
 

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Discussion Starter #3
Does the air conditioning seem to be as effective as it should be if you turn it down to 16 and set the fans to high on the face vents ?

Is the outside temperature reading on the dash accurate ? Do you have Leafspy by any chance ?

The heater uses the PTC heater, the heat pump, or both together depending on conditions. The PTC heater is fast to heat and can produce really hot air, the heat pump is slow to heat up and can only produce moderately warm air, but not truly "hot" air.

When you first turn the heater on and the car is cold it will bring on both the PTC heater and the heat pump in heating mode at the same time. The PTC heater gives that initial quick warm up and blast of really hot air to get the car up to temperature, as it warms up the PTC heater dials back and at some point goes off, leaving only the heat pump producing enable heat to keep the cabin at a comfortable temperature.

This can be seen on Leafspy as it measures the power drawn by the PTC heater and Heat pump separately.

What you describe sounds a bit like the heat pump is not working in heating mode. The PTC heater will only come on initially for a short time, or stay on if there is a very high demand, but for low demands it will rely on the heat pump. So if that's not working then if you are within a few degrees of the set point you'll be getting no heat and would only get heat when you turn it up really high which would be enough to bring the PTC heater back on again.

Another possibility is a fault with one of the temperature sensors, unfortunately LeafSpy does not report the cabin temperature sensor or vent temperature sensors, it only reports the same outside temperature you can already see on the dashboard.

Another test you could try is to plug the car in to your charger, sit in the car with the car off and turn on the remote climate control with your phone. Remote climate control does not use the heat pump for heating, it relies entirely on the PTC heater. So if the car produces warm air in remote climate mode you know the PTC heater is working. You can verify the heat pump is not being used in remote climate mode by the radiator fans at the front not coming on.
Wow that's awesome. Yes I do have Leaf spy, I've only used it to monitor my battery SOH but will check out the temperature readings from it. I'll try to do some testing today with what you suggested to help narrow down the issue.
 

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Wow that's awesome. Yes I do have Leaf spy, I've only used it to monitor my battery SOH but will check out the temperature readings from it. I'll try to do some testing today with what you suggested to help narrow down the issue.
On the Leaf spy page with the big horizontal bar graph the one that says Heater is the PTC heater (obviously enough) but what's not so obvious is that the one labelled A/C is actually the heat pump - regardless of whether it is being used in cooling or heating mode. (Leafspy does not differentiate the mode the heat pump is in, just that it is drawing power)

So if the heater is on turned up high many degrees above the current cabin temperature you should normally see both bar graphs active showing both PTC and heat pump are generating heat (the heat pump will definitely be in heating mode unless the A/C button on the dash is lit) and if the heat is set lower you would normally see only the "A/C" (actually heat pump in heating mode) active with "Heater" (PTC) inactive.

While testing also keep in mind that the system is slow to respond - even if you quickly turn it up to 30C it takes quite a while to slowly ramp up the power, even more so if you only make small adjustments of a couple of degrees C.
 

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i've found mine has always done this. Turning heat on at a sensible temp (say 21) from a cold start will blow hot for a while then give up. You then need to turn it up higher to make it actually blow hot again. I've always just assumed it was trying to save energy by having a very wide band once it reaches the setpoint. IE once it thinks the cabins at 21, it shuts off the heat and waits until the cabin gets to (say) 19 before turning on the heat again. Similarly if you set off on a journey without heat, and after a while think its getting a bit chilly and switch it on, if its near but not quite at the setpoint, say a cabin temp of 20 and you want 21, then it just doesnt bother heating at all.

If you switch AC and heat on together, it will continue blowing hot air the whole time, because running the AC forces it to run the PTC heater continuously. Obviously that approach is significantly more power hungry, but worth it if you dislike the cold and arent pushed for range.
 

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i've found mine has always done this. Turning heat on at a sensible temp (say 21) from a cold start will blow hot for a while then give up. You then need to turn it up higher to make it actually blow hot again.
It "gives up" when the cabin gets up to the set temperature. (Well, it dials the heat output right back) I've checked it with a thermometer in the car and the air temperature is actually what it claims when it dials the heat output back. An actual air temperature of 21 can feel cold when the windows are all cold and you are not being blasted with hot air. 21 in a house feels warmer because you don't have glass windows on all sides and the radiator in your living room is also warming you with direct infrared radiation which the heater in the car doesn't have.

So as soon as the set temperature is reached and the air vent temperature is reduced you instantly feel colder, but that is a perceptual thing. Just turn it up a bit. :)
I've always just assumed it was trying to save energy by having a very wide band once it reaches the setpoint. IE once it thinks the cabins at 21, it shuts off the heat and waits until the cabin gets to (say) 19 before turning on the heat again. Similarly if you set off on a journey without heat, and after a while think its getting a bit chilly and switch it on, if its near but not quite at the setpoint, say a cabin temp of 20 and you want 21, then it just doesnt bother heating at all.
It does have a bit of dead band yes of a couple of degrees. It also responds slowly to control inputs. If you just increase it by 1C and it is already only intermittently bringing the heat pump on (watch the energy consumption screen to see it cycling on and off) then it will bring the pump on more frequently but that will take a while before you feel any real change, especially since auto likes to blow heat on your feet only. This is a bit like TPI heating controls in a house which can take a while to respond as they're changing the duty cycle of a several minute long cycle. So you need to be a little patient.

If you're expecting to increase the setting by 1C and get an immediate blast of hot air you'll be disappointed, the control algorithm doesn't work that way. It will increase the duty cycle and/or power to the heat pump incrementally so after a few minutes you will be a bit warmer, but it's not a sudden change that you will overtly notice, however a few minutes later you will realise that you are actually warmer.

I've experimented with it quite a bit now that the weather is getting colder and it is clearly designed not to "over react", and takes a measured response to any changes you request. It also seems to favour higher airflow of luke warm air to maintain the status quo vs many ICE vehicles which produce a very small flow of quite hot air in the same situation - and this feels quite different as even a small amount of hot air flowing onto your body makes you feel warmer than the car really is.

I actually prefer what the Leaf does to be honest - I hate being blasted with roasting hot air in my ICE car just because I dared to turn the slider up 1 or 2C only for the air to go from roasting hot to too cold a few minutes later when it has overshot the requested temperature. It always tries to get to the target as fast as possible (since it has unlimited waste heat at its disposal) but just ends up overshooting.

The Leaf is much more gradual and measured in its response - if I feel a little cold and turn it up 1C it takes a few minutes but it warms up that amount without overshooting the mark and without using excess energy to do so.

It was 2C on the way to work this morning - the car preheated to 19C while plugged in and I had it set to 20C in auto initially once we set off. I was wearing a shirt and jumper with the heated seat set to low and I found it slightly too cold after a few minutes so turned it up to 21C, a few minutes after that it was just nice and comfortable without being stuffy.

The Leaf actually has a thick layer of carpet underfelt in all the doors as extra insulation (which I discovered when I fitted the wing mirror auto fold kit) which means you don't really need hot air blasting you to maintain a comfortable temperature - even with it being 2C outside the vent air temperature was luke warm once up to temperature but enough to keep the cabin comfy. Well insulated with warm air to keep the status quo feels very different to poorly insulated with hot air to keep the same average ambient air temperature.

Just my opinion and YMMV of course.
If you switch AC and heat on together, it will continue blowing hot air the whole time, because running the AC forces it to run the PTC heater continuously. Obviously that approach is significantly more power hungry, but worth it if you dislike the cold and arent pushed for range.
It's a lot more power hungry in my experience, I avoid turning them both on together unless I'm experiencing fogging or my clothes are a bit wet and I'm trying to get dried out. If you're too cold just turn it up a bit instead. :) Don't get too hung up on the actual temperature setting because it is regulating ambient air temperature but that is not the only factor that controls whether you feel hot or cold. If you feel a bit cold just turn it up a bit higher until you find a comfortable balance, and give it a few minutes to respond to your change before deciding whether that was enough.
 

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Discussion Starter #7
On the Leaf spy page with the big horizontal bar graph the one that says Heater is the PTC heater (obviously enough) but what's not so obvious is that the one labelled A/C is actually the heat pump - regardless of whether it is being used in cooling or heating mode. (Leafspy does not differentiate the mode the heat pump is in, just that it is drawing power)

So if the heater is on turned up high many degrees above the current cabin temperature you should normally see both bar graphs active showing both PTC and heat pump are generating heat (the heat pump will definitely be in heating mode unless the A/C button on the dash is lit) and if the heat is set lower you would normally see only the "A/C" (actually heat pump in heating mode) active with "Heater" (PTC) inactive.

While testing also keep in mind that the system is slow to respond - even if you quickly turn it up to 30C it takes quite a while to slowly ramp up the power, even more so if you only make small adjustments of a couple of degrees C.
I wasn't able to do this as I was having a problem remotely starting the climate from my phone. I thought it was because I had upgraded to Android 11 but when I logged into Nissan Connect on the web, it required me to confirm some new subscription. It was free to confirm but it now has an expiry date of January 2029. Seems like I can log in via phone again.

However, I also noticed that I can't see the heater information you mentioned that is available on Leaf Spy. Here are all the screens of Leaf Spy from a recent screen capture I did. Where do I need to go on this?

TIA
 

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Sorry, I forgot that you can toggle the bar graph to two different modes. Just go to the screen with the horizontal bar graph (your last image) and tap on the right hand end of the graph and it should change to one that says "Batt, Aux, Hetr, A/C". You might need to turn your device to landscape mode to see the power figures beside the graph lines.

BTW if you hold your finger down on the "hamburger" icon in the top right an overlay will appear on the screen showing where all the touch zones are on each page and what they do - this can help you to find some of the "hidden" options like toggling the bar graph mode.

Yes the user interface of Leafspy is kinda clunky and strange to get used to... :)
 
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