HVAC questions

[smkettner]

I am just thinking when it is below freezing the evaporator will be way colder and any moisture thrown in from the road will freeze. This would be very different from a home unit that could even be sheltered from precipitation.

 

[linkim]

Regarding the comments about the LEAF options mentioned in Japanese (http://www.nissan.co.jp/LEAF/OPTIONS), I was finally able to get a brief summary from my Nissan contact based in the US. He said:

"These options are for cold area in Japan . I am not sure if US LEAF has the same options.
1, Steering Wheel Heater Switch
2, Steering wheel with heater
3, Steel arm rear wiper
4, Front seat heater switch
+ PTC heater 5kW
+ Coolant upgrade
+ Door mirrors with heater
ETC is an electric toll collection system only in Japan ."

Don't know if this helps or not.

 

[Nubo]

Simply: You got 5,000 watts (17MBH) max heat available.

That's just it. 17,000 BTU per hour. Enough heat energy to raise over 8 tons of water 1 degree. That's a respectable amount of heat.
Of course it can't be 100% efficient, but still....

 

[EVDRIVER]

Simply: You got 5,000 watts (17MBH) max heat available.

That's just it. 17,000 BTU per hour. Enough heat energy to raise over 8 tons of water 1 degree. That's a respectable amount of heat.
Of course it can't be 100% efficient, but still....

My hot tub heater is 5kw, it takes a looong time to heat it initially, hours and hours. 8 tons is almost 2000 gallons, my tub was about 500 gallons. The way they do the heater is inefficient, they need 4-5kw. If that was a ceramic heater in the dash it would blast you with heat instantly. I sure hope that tank is insulated as well as the lines.

 

[Smidge204]

My hot tub heater is 5kw, it takes a looong time to heat it initially, hours and hours. 8 tons is almost 2000 gallons, my tub was about 500 gallons. The way they do the heater is inefficient, they need 4-5kw. If that was a ceramic heater in the dash it would blast you with heat instantly. I sure hope that tank is insulated as well as the lines.

The heating system in the leaf is 0.47 gallons. The water in the system will heat up at just over 70 degrees per minute.

I would argue that using water as an intermediate has two advantages: First, if you preheat, you are storing some amount of thermal mass in the water (although not much since the volume is so small). The water offers a buffer so the heating element does not have to turn on and off as often. Second, you can (potentially) get better heat transfer coefficients. Potentially.

Truth be told they probably just tried to cut a corner by using a standard heater core and duct system... but it is not a bad compromise IMHO.
=Smidge=

 

[kmp647]

Regarding the comments about the LEAF options mentioned in Japanese (http://www.nissan.co.jp/LEAF/OPTIONS), I was finally able to get a brief summary from my Nissan contact based in the US. He said:

"These options are for cold area in Japan . I am not sure if US LEAF has the same options.
1, Steering Wheel Heater Switch
2, Steering wheel with heater
3, Steel arm rear wiper
4, Front seat heater switch
+ PTC heater 5kW
+ Coolant upgrade
+ Door mirrors with heater
ETC is an electric toll collection system only in Japan ."

I think it makes sense that most of these options will make it into the USA cold spec package
why reinvent the wheel? cold in japan is the same cold as in the USA

no need for the toll collection system
#1, 2, 3, 4 , coolant upgrade, and heated mirrors are all self explanatory

still would like more info on the PTC heater 5kw

any chance you could ask tour contact 2 questions
1. when will the cold spec be an option for USA orders (site says april in Japan)
2 what is a " PTC heater 5kw" ?

thank you in advance
Don't know if this helps or not.

 

[TimeHorse]

On press day (27 Jan 2011) at the D.C. Auto Show I was was able to sit in both the front and the back of the Red LEAF SL w/ ChaDeMo they have on display there; I am manning the EVA/DC booth where we have the first Smart Electric leased or sold in the Western Hemisphere, a genuine Tesla Roadster and an original Rav4 EV, as well as a Solar Prius and a Feiro converted to be totally electric. Our display is next to a Volt you can sit in and manipulate which is next to a Plug-In Prius and behind the Ion red and green sporty cars that I've yet to check out after 3 days manning the EVA/DC display, you have Scion and then Toyota where you can see a genuine 2012 Rav4 EV with the Tesla Power Train prototype and another Plugin Prius that you can get in and where someone rudely removed the shifter knob -- bastards! Pass the Lexus, Honda and Acura and you get to the Nissan pavilion where you can check out but not enter the Red LEAF that is my Facebook Profile picture for this week. Upstairs, straight from CES, at least last I checked, you can see the Ford Focus Electric and Transit Connect Electric as well. If you are planning to go, it closes this Sunday and I will be there one more time so feel free to PM me if you'd like to know when I'll be there.

Anyway, I responded to this thread for a reason and actually it has to do with my conversation with the Nissan floor guys: I asked them about the delays, and they gave me some boiler plate about increasing production, which isn't news and probably is more for fleets than for the Eye-Poked 8, but I did press him on both the Cold Weather Trim and the 6.6kW screw-you-Ford and with the new Dominion Super-Off-Peak rate from 01:00 - 05:00 for EVs being submitted to the SCC 6.6kW charging becomes all the more important to get done in that 4-hour window.

Getting back to the point, they're aware of the push for the Cold Weather Trim and are considering it, but no firm word on either this or the 6.6kW.

In other words, you apparently read this long post to learn nothing new about the Cold Weather Trim.

This is what happens when answers are so hard to come by!

 

[kmp647]

dont worry , we are pretty much used to people at Nissan not really having any useful or solid information

its normal :|

 

[linkim]

To: kmp647

I sent email to Nissan asking your two questions:

1. when will the cold spec be an option for USA orders (site says april in Japan)
2 what is a " PTC heater 5kw" ?

Will let you know when I hear back.

 

[DarkStar]

... and another Plugin Prius that you can get in and where someone rudely removed the shifter knob -- bastards!

At auto shows, dealers and owners usually remove everything that isn't permanently attached, including shifter knobs, to make sure they don't get stolen. At the Portland auto show, some vehicles even had all their tools (for like replacing a spare tire, etc) removed as well.

 

[kmp647]

To: kmp647

I sent email to Nissan asking your two questions:

1. when will the cold spec be an option for USA orders (site says april in Japan)
2 what is a " PTC heater 5kw" ?

Will let you know when I hear back.

thank you!

 

[TimeHorse]

At auto shows, dealers and owners usually remove everything that isn't permanently attached, including shifter knobs, to make sure they don't get stolen. At the Portland auto show, some vehicles even had all their tools (for like replacing a spare tire, etc) removed as well.

Since all our cars are loaners, we just keep them locked, but the booth rep and owners do have keys for make-shift storage; as far is my stuff, I carry it on my back or in an orange chair I smuggle in, parked between the Tesla and the Red Volt. If you see the chair, I'm no doubt there!

I should mention though that we've had specific vandalism of our EVs and Plugins in previous years. That's why we always have someone there monitoring them.

As far as Cold Weather Trim and 6.6kW Option, all I'm saying is for an extra 8-month wait, they *@$%^ well better include those as options when we Atlantic Coasters order and they better be standard options on the 2012 LEAF!

Not saying they should be mandatory, but give us the bloody option already!

 

[Coffee_Slurry]

I remain puzzled why the Japanese cold-weather kit calls out the 5kW PTC Heater when it is apparently standard on the NA cars.

So.. do the Japanese cars get a different (smaller/missing) heater by default, or is the list just calling out redundant non-optional features that help with cold?

We've been over this in other threads, but there are good reasons to use a liquid 'coolant' loop when running a high voltage heater.

And I would indeed expect efficiency to be 100% for any electric heater. The only loss might be to heat expelled outside the cabin.

 

[linkim]

I received short message from Nissan USA engineer regarding cold weather issues discussed in this thread.

He said he cannot access to future products information from Japan, but guesses cold spec LEAF will be available when we start to sell US-nationwide in fall 2011.

5kW PTC heater is for passenger compartment heating via air. It is the same function as conventional ICE cars, but energy source is not waste heat from engine. It consumes battery, which means shorten the range.

Unfortunately not much new to add.

 

[kmp647]

thank you for your help!

I guess we will find out by "late summer 2011" when tier 2 can order

at that point I would expect pricing and availability for "cold spec pkg" to be announced

and possibly a 2012 Leaf MSRP and options to be announced

Be sure to let the engineer know how important the cold spec package is to us east coasters!

 

[EVDRIVER]

I think that package will be there before then.

 

[kmp647]

I hope you are correct!

 

[Kataphn]

Anyone know where the "in cabin microfilter" is located? Just curious!

 

[rawhog]

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