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Discussion Starter #1
My heating stopped working suddenly. CanZE showed low evaporator pressure. Garage re-gassed (£120) and said it was fixed. It wasn't - no heating. Tried hairdrier trick several times, and removing fuse 3 several times with no luck. Left F3 out overnight, this morning got "check electrical system", put fuse back in and error cleared, heating then worked! Thought it was fixed at that point, but no sign of the compressor running - no noise, or fan, but drawing up to 2kW. It seems Zoe can resistively heat at up to 2kW.
The gas preesure was .7 bar when "empty" and ~3.5 bar when "full", drawing power or not , which is consistent with the saturated vapour pressure at the outside temperature, without the compressor running. Any comments/suggestions?

Vapour pressure chart 4/33:
https://www.honeywell-refrigerants.com/india/?document=2008-purdue-conference-low-gwp-refrigerants&download=1
 

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Discussion Starter #2
It was not the fuse fiddling that caused the resistive heater to operate, it was outside temperature. It comes on when the car is turned on below about 6 C indicated temperature, and turns off when the temperature is increased to about 7-8 C. The extra <=2 kW resistive heating explains why the heater outputs more at low temperatures, it is burning electrons fast.
 

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Co-author of CanZE. Q210 nov 2013
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I am surprised. What ZOE model? AFAIK the non Nordic models have only a 12V heater for the windshield which can never do 2kW. The ZE50 (again AFAIK) has a resistive heater, but only for the battery, not for the cabin, and isn also lower rated. But I forgot the numbers to be honest.
 

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Discussion Starter #4
2014 22kWh Dynamique Intens. I was surprised, but it seems fairly clear. The heat can be directed to the dash or windscreen, and I presume, anywhere, as normal.
 

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I am surprised. What ZOE model? AFAIK the non Nordic models have only a 12V heater for the windshield which can never do 2kW. The ZE50 (again AFAIK) has a resistive heater, but only for the battery, not for the cabin, and isn also lower rated. But I forgot the numbers to be honest.
That's interesting. It might explain why Bjorn is getting lower range in colder temperatures.
 

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My daughters car stopped the AC heating rattle early in the winter but still heats up so must have a resistive heater.
It is a 2015 22kw Dynamique.
The AC pressure reports OK and we have left it until its service in a month or so to get it diagnosed.
 

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Speak, Eevee!
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There is a 14V heater for the cabin on the 22kW Zoe and it's on all the time whenever heating is used. It wouldn't produce much heat, maybe 400W, certainly not 2kW. This was all confirmed by DSG when I had my heating checked over last year, they observed it operating in their workshop (cold but not 5-7C cold). It looks like it isn't present in the R110 though.
 
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Discussion Starter #8 (Edited)
400 Watts seems a bit pointless for cabin heating, it would be useful to keep something dry though. CanZE shows a minimum of 0.3 W 'heating' power all the time. There is no doubt in my mind that there is ~2 kW resistive heating as the car was quite toasty today with re-circulation on, and with CanZE showing a refrigerant pressure of 2.9 bar. It would make sense to have resistive heating in series, and after, the heat exchanger to boost temperature output when the heat pump is not operating efficiently, and with low available output power. It also means it can defrost if the heatpump fails. :)
 

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Speak, Eevee!
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I think rather than as a heat source as such, it's mostly for defrosting the heat exchanger if I have my terminology right? But I suppose you might feel a tiny bit of warmth to the air that comes out. Never seen any evidence of anything bigger.
 

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Garage re-gassed (£120) and said it was fixed. It wasn't - no heating.
My choice would be to go back to the garage and say it's not fixed, even if it was re-gassed. They have to sort it out.

First generation Zoe does have a specific temperature point where it fully engages heating, and your 6-7C threshold is accurate. However, my previous 22kWh Zoe has never put out 22C in the cabin when left in Auto 22C; during the last winter I kept it Eco-off, 24C, regardless of outside temperature. The auto function between 6C and 11C is quite horrendous at the default 22C.
 

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Discussion Starter #11
I think rather than as a heat source as such, it's mostly for defrosting the heat exchanger if I have my terminology right? But I suppose you might feel a tiny bit of warmth to the air that comes out. Never seen any evidence of anything bigger.
You need to break your heatpump first to find the truth..
 

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Discussion Starter #13
My choice would be to go back to the garage and say it's not fixed, even if it was re-gassed. They have to sort it out.

First generation Zoe does have a specific temperature point where it fully engages heating, and your 6-7C threshold is accurate. However, my previous 22kWh Zoe has never put out 22C in the cabin when left in Auto 22C; during the last winter I kept it Eco-off, 24C, regardless of outside temperature. The auto function between 6C and 11C is quite horrendous at the default 22C.
It looks like you do not get the resistive heater in Eco, but I am not certain.
 

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There is some resistive heating in the UK zoe 22kwh. When my heating broke I got like warm air when the outside temp was below 6c but over this I got just cold air. This pulled about 2kw from the battery judging by the instant consumption display
 

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Discussion Starter #15
There is some resistive heating in the UK zoe 22kwh. When my heating broke I got like warm air when the outside temp was below 6c but over this I got just cold air. This pulled about 2kw from the battery judging by the instant consumption display
Did you need a new compressor, or was there some software fix to re-enable the compressor after a re-gas, such as climate controller update?
 

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I think any car with heat pump heating will have a resistive heater of minimum 2kW to assist defrosting in very low temperatures as they become very inefficient at temperatures below zero, just when you need heat.
 

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Discussion Starter #17
Once the pump is running at maximum speed it is operating as a fixed displacement pump. Therefore the refrigerant mass flow rate will drop as the inlet pressure drops with with lower vapour pressure due to a colder evaporator, as well as the lower thermodynamic efficiency due to a bigger temperature difference between the hot and cold heat exchangers.
 

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Once the pump is running at maximum speed it is operating as a fixed displacement pump. Therefore the refrigerant mass flow rate will drop as the inlet pressure drops with with lower vapour pressure due to a colder evaporator, as well as the lower thermodynamic efficiency due to a bigger temperature difference between the hot and cold heat exchangers.
I have no idea what you said, but I like how you said it! (y) (It's my ignorance)
 

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Did you need a new compressor, or was there some software fix to re-enable the compressor after a re-gas, such as climate controller update?
new compressor, climate computer, piping and regas. After all that it still wasn’t working, they spent 3 months on it and in the end they sent the cars data to france Who identified there was a faulty sensor in the AC expansion pipe, it’s a £100 part after they spent £2k+ replacing other bits ?
 

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Speak, Eevee!
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Now imagine how annoying that would be without a warranty extended or otherwise ;)

It's interesting going through all this debate about the resistive heater again just like last year. It remains one of the Zoe's greatest mysteries. Surely at some point someone with a scrap one can pull it to bits and identify the part and its spec.
 
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