Heating question.

[Aitch1]

Now that the chilly mornings are with us I'm having to use the heater more. Unfortunately the heater doesn't dish out much heat for quite a few miles. In the 'good ole days' you could fit a winter thermostat, obviously not so in modern cars. So, is there any tricks to get more life out of the MG heater? In the same vein, I read somewhere in these columns that the heating is fed by the ICE, not the large battery. If this is the case, what happens when the car is in EV mode, which mine usually is for a few miles. How does the heating system work, or not, in this situation? Please don't advise me to use the iSmart app, I had enough problem getting that sorted before I gave up in disgust.

 

[Tim19]

The heating system is fed by the combustion engine. If the heating controls are set to a temperature higher than outside the system will start the engine to warm the coolant in order to heat the cabin. It will not ruin all the time but enough to get the heat required.

 

[Aitch1]

The heating system is fed by the combustion engine. If the heating controls are set to a temperature higher than outside the system will start the engine to warm the coolant in order to heat the cabin. It will not ruin all the time but enough to get the heat required.

Mmm. Tricky. Let me get this straight. One of the benefits of this particular hybrid is that it runs in EV mode more so than other hybrids and therefore more miles to the gallon. But if I also want a warm car I have to force the engine into HEV mode,i.e using petrol? Can't quite grasp the sense in all that. Thank you, anyway Tim. Much appreciated

 

[Tim19]

It does seem a bit back to front but we can only assume that they did the maths and worked out that an electric heater element was less efficient than using the combustion engine to provide the same heat. It would have had to run from the large high voltage battery and maybe the amount of charge it would take would mean the engine running more

 

[Cooperman]

It does seem a bit back to front but we can only assume that they did the maths and worked out that an electric heater element was less efficient than using the combustion engine to provide the same heat. It would have had to run from the large high voltage battery and maybe the amount of charge it would take would mean the engine running more

Have to agree with you here Tim.
Not sure where you are coming from Aitch?, as your "winter thermostat" not really relevant regarding the heating system as most ICE coolant runs up to about 90degC working temp anyway and normally has some sort of heat exchanger feeding the interior heating system. To maintain the required internal temperature of say 22degC the ICE coolant temperature probably needs to be well above this depending on the efficiency of the heat exchanger system, but once the engine is warm it will maintain coolant heat for a reasonable time. So the ICE doesn't have to run all the time to keep the interior at the required temp and don't forget while the ICE was bringing the coolant temperature up for the heating it was also charging the EV battery. After the initial heating period the EV to HEV running ratio should maintain both the EV battery charge and the coolant temperature, although this will probaly favour the ICE more during cold weather leading to slightly poorer fuel consumption I expect.

 

[Aitch1]

Have to agree with you here Tim.
Not sure where you are coming from Aitch?, as your "winter thermostat" not really relevant regarding the heating system as most ICE coolant runs up to about 90degC working temp anyway and normally has some sort of heat exchanger feeding the interior heating system. To maintain the required internal temperature of say 22degC the ICE coolant temperature probably needs to be well above this depending on the efficiency of the heat exchanger system, but once the engine is warm it will maintain coolant heat for a reasonable time. So the ICE doesn't have to run all the time to keep the interior at the required temp and don't forget while the ICE was bringing the coolant temperature up for the heating it was also charging the EV battery. After the initial heating period the EV to HEV running ratio should maintain both the EV battery charge and the coolant temperature, although this will probaly favour the ICE more during cold weather leading to slightly poorer fuel consumption I expect.

Wow!

 

[Deleted member 18108]

The heating system is fed by the combustion engine. If the heating controls are set to a temperature higher than outside the system will start the engine to warm the coolant in order to heat the cabin. It will not ruin all the time but enough to get the heat required.

It's also worth bearing in mind that the engine runs on the Atkinson cyle, which is allegedly more thermal efficient. This I assume also explains why it takes longer to heat up. even when the engine fires up. It is perhaps more akin to a diesel engine than a petrol in that regard.