Self powered Frostheater idea.

[fouillard13]

Ok I’ve been thinking. Would this work?

1. How long can a Frostheater run off of a car battery for? Even a large fancy battery if needed

2. how long would it take for the alternator to charge a fully dead car battery from question 1?

3. how long does the Frostheater need to run to make a car happy that’s sat at -25c for 12+ hours?

Why would this not work: Have a second battery in the trunk wired to the Frostheater. Maybe even with a timer so it comes on at 5pm. So when I’m off work at 7pm and it’s approaching -30c outside with no plug ins, the Frostheater ran for 2 hours off a sacrificial auxiliary battery which essentially re charges for free every night off the alternator and drive home. Then when I drive I can recharge that battery, maybe even use a little solar panel somewhere too during the day if needed, and repeat forever. Always having a warm car AND not needing to plug in. Yes? No?

so then essentially you’ve got a Frostheater that has the ability to run anywhere that has no plugins, for an hour or two, which is just enough to not have an ice cold -25c struggle start that blows oil cooler gaskets after a long day in the cold?

 

[Mozambiquer]

I'd go with a webasto heater.

 

[Vince Waldon]

In terms of question 1: This one comes up almost every year and unfortunately watts are watts.

Back of envelope math: 1000W Frostheater, inverter at 90% efficiency: draw on the battery will be (1000W/12V) X 1.1 or 92 amps.

Standard TDI battery is 80 Ah (at room temperature and at a much lower load IIRC 10% or 8 amps) so on a warm summer day you'll get much less than an hour, MUCH MUCH less than that if the inverter battery is cold:

Many many many more watts in combustible fuels.

In terms of question 3: my Edmonton experience is that if you can't plug it in for 3 hours don't plug it in at all... if the warm-up time is too short the warm coolant fools the CTS into thinking the block is warmer than it has time to get to, and starting is actually worse.

 

[oilhammer]

Wear a coat.

 

[Prairieview]

And long pants. I got mowrons running around here in little shorts today!

 

[fouillard13]

So let’s replace the battery with a medium sized jumper box which would 100% power the Frostheater for 3 hours. How long would that take for an alternator to charge it then? Or when you get home, plug the Frostheater in AND the jumper box to charge all night. Both plugs up front and next to each other. Have it on a timer to kick on 2-3 hours before you get to car. Warm start at -30 without plugging in all day. Simple. Right?


Jumper box isn’t cheap, but can always be resold at 80% when done with it in a few years and holds value. Not necessarily true about a used webasto setup.

just thinking out loud is all here and trying not to spend $2500 on a webasto to burn diesel which its approaching $2 a liter and more in the coming months.

Either way, I’ve got a new starter on the way. New glow plugs in. And I’ll upgrade battery if the starter doesn’t help cold starting. Should be fine at that point, even unplugged.

 

[fouillard13]

Wear a coat.

Helly Hansen wool onesie, sweat pants, carhartt bibs, long sleeve shirt. Hoodie. Jacket. Balaclava. Heat cranked all day. This -30, feels like -38c cold spell is no joke. I’m fine. It’s the unplugged car that ain’t happy haha.

 

[jmodge]

Take your car to an exhaust shop to Fix your exhaust first before it kills you. Then stick a light with an incandescent bulb on the coolant manifold off the back of the head. Easy trick for the lazy and procrastinating type. Don't hold it against me, Your description, not mine

 

[Vince Waldon]

Jumper boxes are designed to deliver a few momentary bursts of high current to run the starter... not hours and hours of 90+ amps.

 

[Windex]

If you're dead set on going this route, you'd need a bank of batteries, not just one. They should also be AGM to withstand the deeper discharges.

We see these loads in bunk HVAC all the time. Charge times are roughly 1/3 to 1/2 total run time, but that's with a 250a Remy commercial truck alternator running all highway.

 

[fouillard13]

Not dead set. Just wondering if anything like this can be done efficiently or safely or if it’s possible with any amount of money. Maybe I’m onto something. Maybe I’m an idiot. I dunno. Probably the latter.

Maybe jumper box was the wrong work. The jackery 1000 power station powered someone’s laptop, speakers, and lights for a festival show all weekend and runs another guys CPAP machine for 12 hours a night while he camps for a week. But it’s also $1200.

 

[fouillard13]

Kits cost nowhere near that.
Most universal thermo top evo webasto kits are around $1000 CDN new. Try find a used one

a webasto also only provides cab heat right? Does it do anything for the cold motor?

 

[Andyinchville1]

HI,

I think a good way to go would be to buy one of those $150 Chinese diesel heaters off ebay (typically 5K to 8K BTUs) ... they don't consume as much power as the all electric heaters because they burn diesel to make heat not electricity.

As a side benfit of that heater you can divert the heat (air) into the cabin (toasty warm! or rig up a duct under the hood to warm up the engine compartment more (maybe even keep the battery warm also!!) BUT you would have to Fab up a heat exchanger for the exhaust to blow into to heat the engine coolant (maybe rigging the factory exhaust cooler to run the exhaust of the diesel fired heater through it?).

Anyways, I thought of doing that idea myself but have unfortunately not had the time to tinker lately.

Hope this helps.

Andrew

PS - Food for thought ... maybe try replacing our stock small battery with a group 31A battery (bigger reserve capacity , more CCA AND cheaper) ....I put one in place of 2 batteries on my 1990 F250 diesel BUT had to clearance the hood a bit (hammer time!) ....I had the battery with the screw on terminals (had to add the std lugs) BUT that added height and caused fitment issues so I exchanged it for one that already had battery terminals (Group 31A has the terminals on it not just screw lugs sadly AFTER I hammered the hood bracing ...oh well extra space! ) ... Group 31A may be hard to put under a Jetta hood but I am thinking of doing that IF I add the heater .... may require cutting and ??

 

[burpod]

while it wouldn't help with starts, there are things you can do in the tune to help a decent amount with improving cold weather performance.

i assume you've done the simple things like blocking off the grill and intercooler for those kinds of temps. but if all hardware is 100% good, it should start fine in those temps. a frostheater is great to plug in few a couple hours to get a nice bump start, but aside from that.... doing something along the lines of what you're thinking just really isn't physically possible, there's no free lunch there...

 

[ticaf]

In theory it's possible of course.
In practice, you'll need a few deep cycle batteries in the trunk, and upgrade your alternator to fast charge them.
The diesel heater is also not that easy to install.

I'd buy a gasoline car with remote start if I were truly after some quick engine heat.

 

[ToxicDoc]

This doesn't seem that hard. Frost heater is a 1000 watt device. Divided by 12.6 amps for resting battery = about 80 amps. A 500 amp battery can discharge about 250 amps before damage, so that would give him up to 3-4 hours of useful heating time with a trunk-mounted auxiliary battery. d [strike that as an error. He'd still need 250 aH actual capacity for 3 hours of heating - very pricey]. Include a battery isolator in the system and he can recharge about 50 amps/hr on the way home and plug in a charger for whatever his alternator did not complete when he gets there.

 

[GlowBugTDI]

Pick your poison

If you like that sort of thing

 

[jettawreck]

This doesn't seem that hard. Frost heater is a 1000 watt device. Divided by 12.6 amps for resting battery = about 80 amps. A 500 amp battery can discharge about 250 amps before damage, so that would give him up to 3-4 hours of useful heating time with a trunk-mounted auxiliary battery. Include a battery isolator in the system and he can recharge about 50 amps/hr on the way home and plug in a charger for whatever his alternator did not complete when he gets there.

Inverter is not very efficient and as such that math will need to take in that loss plus the additional loss from long (big) wire from the truck relocation.

 

[Windex]

Dunno if it was answered above - webastos and espars (eberspachers) are both available in air-air and air-coolant varieties.

If it's block heating you are looking for then you would want the air-coolant type.

Plumb it in to a heating circuit, provide it fuel, and run it on a timer. Truly the best solution for what you are trying to accomplish.

There are a few threads here where others have done the same for the same reason as you - no place to plug in in very cold temps.

 

[Lug_Nut]

This doesn't seem that hard. Frost heater is a 1000 watt device. Divided by 12.6 amps for resting battery = about 80 amps. A 500 amp battery can discharge about 250 amps before damage, so that would give him up to 3-4 hours of useful heating time with a trunk-mounted auxiliary battery. Include a battery isolator in the system and he can recharge about 50 amps/hr on the way home and plug in a charger for whatever his alternator did not complete when he gets there.

When the physics are understood, it IS that hard.
Batteries are rated in amp*hours, not amps. That fanciful "500 amp battery" isn't an accurate description of the battery's capacity. The "3-4 hours" at about "80 amps" will require is a 240 to 320 A*Hr. battery. A Trojan 1275 battery deep cycle will put out 120 A*Hr when discharged over a 5 hr window, or 24 A*Hr per hour. If the battery were able to hold 12.6 volts while being discharged at that rate, that would be 300-ish watts of power available from that one battery. To get 1000 watts, would require 3+ of these batteries.
Recharging at a 50 amp (not A*Hr.) rate will require twice as long a drive home as the pre-heat duration. Four batteries, each discharging at 24 amps, is 96 amps, with recharging at 50 amps. Three hours of heat from that four battery bank in the trunk will require a 6 hour drive time to put back the power.

The pre-heater is a resistance unit. it doesn't care if AC or DC, so avoid the inverter completely and feed it with direct current from the batteries.
You'll still need to tote a 1/4 ton of battery to get any meaningful battery power for a heater.

 

[jmodge]

...and this is why I say to the OP, just put your lamp on the back of the head (the one on your car). Save the other head for something else. This worked on mine when I had no functioning glowplugs. Saves wear and tear on the starter also.

 

[Vince Waldon]

You'll still need to tote a 1/4 ton of battery to get any meaningful battery power for a heater.

And. at $500 CDN each, a $2000 investment.

Alternatively, Webastos show up on FB pretty regularly... here's one here in Alberta for $750: https://www.facebook.com/marketplace/item/3392611557638874/

Espar is another common brand: $700
https://www.facebook.com/marketplace/item/547391257096587/

 

[ToxicDoc]

You're right Lugnut. I wasn't thinking and crunched numbers based on cca which isn't capacity.