Honda Jazz Mk3 Heater on Ex-Navi

[ramaka]

I am a new driver with first car as Honda Jazz MK3 Ex-Navi. I don't know how heaters works in Cars hence want to know how much time does it normally takes for the heater to start blowing warm air when the outside temperature is in the range of 5-10 degrees. What I noticed is, it start blowing warm air after 5-10 minutes of driving, is that normal?

After staring the car I set the temperature to hi and climate control to auto mode, and then once after 5-10 minutes when it starts to blow the warm air I set the temperature back to 20 degrees or so. Am I doing rights here and Am I using the heating system correctly?

Also can someone please explain the mechanics behind the functioning of Heater in general.

[jasonevans]

About 5mins is normal as the engine has to get some heat into it before it opens the heater valve.
Colder temps take a bit longer.

What I normally do is set the temp to cold for about 3-4 mins first so engine gets warmer a bit quicker and then turn heating on.  Seems to work better that way for me.

[Lord Voltermore]

Yes its not unusual to take 5 minutes to get useful cabin  heat when starting  a car from cold.

On cars with an internal combustion engine (petrol or diesel)  the engine is kept cool by circulating coolant (a mixture of water and antifreeze) around the engine   and then cooling it by passing it through a radiator at the front of the car.  Engines work best  when hot - with the coolant at around boiling point. (Its best drive more gently until the engine has reached its operating  temperature. There is normally a blue light telling you the engine is cold. Take it easy until this light  goes out) )   If the air passing through the cooling radiator is  cold it can take longer to warm up.  There is normally a thermostat  in the system that stops the coolant circulating until the engine is warm , so it heats up quicker. 

For cabin heating there is a second small radiator  behind the dashboard.   When you switch on heating  a valve is opened so some of the engine coolant passes through this heater radiator and it gets hot.When you adjust the heating level it adjusts the rate of flow of hot coolant  (which may not yet be hot  )
Air is directed to the cabin and heats up as it passes through this little hot radiator.  Some comes in as you drive along, or you can boost the amount of air by using the fan.     You can also distribute the hot air where you need it most , such as to a frosty windscreen , or your feet  or a bit of both.  You may need to adjust air flow , fan speed etc to suit your needs and comfort as the car warms up.
A car with climate control  can adjust heating and air distribution automatically  using electronics  . Or you can set things manually. Your system can also control and cool temperature automatically (or manually) by using air conditioning.

Put in very simple terms Airconditioning uses a  second separate  system of  radiators to cool air below the ambient air temperature.   

There is quite a bit to learn to have full control of heating and cooling.     Its probably in the drivers handbook which you can download free from Honda as a pdf

https://www.honda.co.uk/content/dam/local/uk/cars/owners/manuals/2018%20Jazz%20Owners%20Manual.pdf

[Toptek]

I'm not a big lover of the touch screen, much prefer a few knobs and it doesn't seem to shift much air compared to other cars I've owned.
However, I tend to mostly set it to "auto" and let it do its thing. In the colder months, it waits for the heating to warm up to have something warm to circulate, therefore, you can increase the fan speed manually and eventually it will get warm enough for you to press the auto icon. I have to do this as ours suffers a lot from condensation in the winter.
Also, I find in summer I tend to increase the fan speed if I'm feeling particularly warmer than what the car's system is deciding to do, then again pop it back on auto.
It would appear most people say to leave it mostly on auto to ensure the AC system seals are lubricated.

[jazzaro]

I am a new driver with first car as Honda Jazz MK3 Ex-Navi. I don't know how heaters works in Cars hence want to know how much time does it normally takes for the heater to start blowing warm air when the outside temperature is in the range of 5-10 degrees. What I noticed is, it start blowing warm air after 5-10 minutes of driving, is that normal?

After staring the car I set the temperature to hi and climate control to auto mode, and then once after 5-10 minutes when it starts to blow the warm air I set the temperature back to 20 degrees or so. Am I doing rights here and Am I using the heating system correctly?

Also can someone please explain the mechanics behind the functioning of Heater in general.

In full-auto mode the fan runs slowly until cooling liquid temperature reaches about 45°C, it takes 3-10 min depending on usage: driving in uphills the engine will warm quickier than downhill.

[embee]

IMO the HVAC (heating ventilation air conditioning) system in the mk.3 Jazz is fairly poor,  nowhere near as good as my 13yr old Yaris  for example. I have a 2018 Jazz, just the manual system.
A good description by LV above,  I'd just add that some cars continually circulate coolant through the cabin heater matrix and the controls vary the air side flows, I don't know how the Jazz operates, it doesn't really matter for the user  but it can affect how quickly the system can respond.
My Jazz is slow to give cabin heat, it's a downside of having a very efficient engine with lower heat rejection to coolant.
You can get better results sometimes by using as low heater airflow as you can while it warms up, less air but higher temperature feels better than more air at lower temp (you are cooling the heater matrix), but the gains might be relatively small.

[jazzaro]

My Jazz is slow to give cabin heat, it's a downside of having a very efficient engine with lower heat rejection to coolant.

My Jazz is faster to give heat than my old 1.2 16v Renault, even if its japanese engine is much more efficient. Must be due by fast heating strategies, antipollution rules want the engine (and kat) to reach working temperatures as faster as possible.
I also have a Euro5 Suzuki motorbikie: in first minutes after startup, instant fuel consumption is very high till the engine reaches about 60°C, then it drops.