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914World.com _ 914World Garage _ Electric Heat
Posted by: 914fun Jun 28 2008, 02:11 PM
Anyone know of a way to add electric heat and defrost? I have no heat exchangers and instead of adding them Id like to come up with a way to add some heat with electric heaters. The car will not be driven when it is very cold out.
Posted by: Cap'n Krusty Jun 28 2008, 03:16 PM
Electricity is, by far, the most energy consuming form of changing the temperature. You'll need a HUGE alternator, or maybe a Honda portable generator in the front trunk, to make any real heat. Fact'o life .................... The Cap'n
Posted by: davep Jun 28 2008, 04:38 PM
Can't argue with that observation. I think a 200 amp alternator would be required.
Posted by: GeorgeRud Jun 28 2008, 04:54 PM
I think that many have considered it, but nobody has really made a working system. It comes down to using heat exchangers or addind a gas fired heater using early VW or early Porsche 911 technology.
The old Eberspacher gas heaters did put out amazing amounts of heat, but I've only ever seen one photo of one in a 914. If anyone knows where that photo can be found, I think many of us would like to see it. I seem to remember someone had a web site with pictures of 914 accessories.
Posted by: r_towle Jun 28 2008, 05:05 PM
I think that many have considered it, but nobody has really made a working system. It comes down to using heat exchangers or addind a gas fired heater using early VW or early Porsche 911 technology.
The old Eberspacher gas heaters did put out amazing amounts of heat, but I've only ever seen one photo of one in a 914. If anyone knows where that photo can be found, I think many of us would like to see it. I seem to remember someone had a web site with pictures of 914 accessories.
http://www.914world.com/bbs2/index.php?showtopic=63365&hl=Eberspacher
Posted by: Todd Enlund Jun 28 2008, 05:54 PM
How about oil heat?
Posted by: HeloMech Jun 28 2008, 07:37 PM
they have a little 12vt dc heater/blower thing at harbor freight for like $12. I just bought one for a guy at work who's heater blowers aren't working. He's been able to park next to his garage lately so he hasn't needed to try it. It's very small and we're hoping it will work for defroster. Just sits on the dash. Goofy looking little thing. Must be FAST though... it's yellow.
YHAF.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=96144
just saw this one online too.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=94592
Posted by: davep Jun 28 2008, 07:50 PM
they have a little 12vt dc heater/blower thing at harbor freight for like $12.
The company I work for import those heaters. As technical manager, I have to test them. The phrase "totally useless" adequately describes them.
The only real solution is to get SSI heat exchangers and rebuild the factory system.
Posted by: 904svo Jun 28 2008, 08:05 PM
This is the design that I use for a heater in my 904.
Posted by: Rand Jun 28 2008, 08:39 PM
they have a little 12vt dc heater/blower thing at harbor freight for like $12.
The phrase "totally useless" adequately describes them.
The only real solution is to get SSI heat exchangers and rebuild the factory system.
Agree, those electric things are useless. The wire gets hot before it does anything to the windshield. Electric simply cannot produce enough heat to do any good off the regular wiring.
While I agree that heat exchangers are the best solution, there are a couple of other options. One is the gas Eberspächer as Rich mentioned. The other is more of a compromise, but works for some of us:
http://www.golfcarheater.com/product.sc?categoryId=1&productId=3. Can sit in a cupholder. Can be mounted to point at windshield. Portable catalytic infrared, runs off a gas bottle. Just beware - get one that is rated indoor safe! (Otherwise carbon monoxide poisoning is a risk.)
Posted by: bandjoey Jun 29 2008, 12:10 AM
You can always to the heat pump route. Home depot has them on the July 4 sale for $99.
Attached image(s)
Posted by: HeloMech Jun 29 2008, 02:13 PM
Yeah, I just don't drive MY car when weather is that crappy. But he lives at the beach and even when the weather WILL be nice, he's got fogged windows in the morning on the way to work. He's getting nothing out of either blower and his wiper motor appears to be inop.
Thought it would be a shot in the dark for him to clear his windshield enough to get going down the street. I mean, really, come on.. it's got a flip out handle so he could dry his hair too.... 
What if I chop the wires and solder in a larger guage... if he decides to use it at all... I mean, if he'd get the 944 and turbo 944s out of his garages, he'd be able to put the 914 in there and he wouldn't HAVE fogged windows in the morning!!!
man... I LOVE that generator/window AC idea... I wish I'd have thought of that while I had the PT Cruiser!!
Posted by: Tom Jun 29 2008, 02:48 PM
Power requirements would be too great. Power in watts is Current (amps) X voltage. P=IE Say you have a 1200 watt heater - think hair dryer. Divide 1200 by volts (12) and you would need 100 amps. Not only large alternator, but some pretty large wire to supply the heater also.
SSHE's and a good blower!
Tom
Posted by: Mike914 Jun 29 2008, 09:08 PM
Power requirements would be too great. Power in watts is Current (amps) X voltage. P=IE Say you have a 1200 watt heater - think hair dryer. Divide 1200 by volts (12) and you would need 100 amps. Not only large alternator, but some pretty large wire to supply the heater also.
SSHE's and a good blower!
Tom
Remember that the blower needs a check valve to prevent cooling air loss when its not running...
I, f you change the voltage to 120 you only need 10 Amps... The heaters in my electric conversion are "1500" Watt ceramic heater cores running on 144VDC, drawing 15 Amps for the pair. Serious heat! Mounted under the cowl next to the hood springs so losses through the longs are avoided, as well as the condensation in there.
If you are serious about electric heat, just get a huge deep cycle battery, (like a Caterpillar batt!) and an inverter that can handle one of those 1500 Watt heaters (Say 3KW continuous rating.) Recharge the battery at home so it does not need to be connected to your dinky alt, in summer time you can take the whole thing out and leave it home! You need to size the battery to provide power for the length of you trip of course.
P.S.
You can see pics on Roadglue of my heaters. (Alt Power forum.) Still working on it!
Posted by: Krieger914 Jun 29 2008, 09:41 PM
How about adding the components for heated seats. 
Posted by: boxstr Jun 29 2008, 10:54 PM
Hot seat at CAMP
CCLINHOTBUTT
Attached image(s)
Posted by: 914fun Jun 30 2008, 11:46 AM
This is the design that I use for a heater in my 904.
Hey 904svo! I like this idea. Lots of other good ideas also. Thanks guys. Will likely try this one first. How did you come up with the Shroud over the oil cooler. It will not put off an oil smell, right? Then I just splice into the heat ducts, right? Where is the oil comming out of the motor. I have an oil cooler system the p.o. put in. There is about 11 Feet of oil line. The p.o. said he dose not trust it to pump the oil very good, so he unhooked it. What oil pump would you recomend to pump that far. I have not picked up the car yet so I have not looked at his systm but I bet its doable. Thanks for taking the tim to make the drawing.
Posted by: 904svo Jun 30 2008, 02:23 PM
Here are some pictures of my system, I used a spare 914 oil cooler and made two
shrouds for the air. 
Posted by: 904svo Jun 30 2008, 02:26 PM
Here are the pictures of the oil return system.
Posted by: 904svo Jun 30 2008, 02:28 PM
The oil pump is a low pressure, low volume pump that can be bought at
Harbor Freight.
Posted by: 914fun Jun 30 2008, 03:04 PM
Here are some pictures of my system, I used a spare 914 oil cooler and made two
shrouds for the air.
Looks good. Where did you mount tthe oil cooler and what size lines. Great picturs. Thanks for being so helpful.
Posted by: 904svo Jun 30 2008, 06:42 PM
In my car (kit 904) it's mounted in the right front fender with 3/8 rubber hoses
feeding it. You should be able to mount it in your engine compartment with shorter
hoses to the taco plate and valve covers. It only has oil in the lines when you turn
on the pump it drains back into the engine when not in use. I used the heater lever
to turn on the pump and the hot air blower.
Posted by: morph Jun 30 2008, 08:14 PM
how well does it work ?
does it blow good heat ?
james
Posted by: 904svo Jun 30 2008, 09:05 PM
how well does it work ?
does it blow good heat ?
james
It works very well when the oil gets over 185 degrees, it would work better
if a larger heater core were installed. I was limited on space where I place it. I used the fresh air blower resistor pack on the original heater blower motor to
give me 3 speeds. If you look at the design you will see I'm treating the oil as
water with the design thats why I used a separate oil pump to control the oil flow.
In order to get the heat back in the oil I return the oil to the heads, just like
they due in airplane engines, this also cools the heads.
Posted by: swl Jul 1 2008, 09:08 AM
a previous discussion:
http://www.914world.com/bbs2/index.php?showtopic=76360
Posted by: r_towle Jul 1 2008, 09:50 AM
Has anyone looked into using a peletier device/ thermoelectric device?
I was under the impression that they produce heat/cold with low amperage requirements. This electric requirement is lower than a hair dryer type electric heater.
http://www.americool.com/aa.htm
One example.
I know that this has been tested and used in both Nasa and submarines with great success. It is also used in the Iraq war because it is low sound, this keeps it more stealth,,,all the while cooling the computers in the backs of the trucks, or on the backs of the soldiers.
Couple of questions.
What is the largest alternator that we can get for a 914?
Can a stock alternator be rewound (enough room) to make a large output
rich
Posted by: Bartlett 914 Jul 1 2008, 11:29 AM
In my car (kit 904) it's mounted in the right front fender with 3/8 rubber hoses
feeding it. You should be able to mount it in your engine compartment with shorter
hoses to the taco plate and valve covers. It only has oil in the lines when you turn
on the pump it drains back into the engine when not in use. I used the heater lever
to turn on the pump and the hot air blower.
Doesn't this make for oil levels in the engine vary tremendously? What about using check valves in the lines to keep them full to help keep engine oil levels consistent.
How much does this cool your oil temperatures? Maybe you should have a thermostat in the oil to control when the pump will be allowed to run.
Posted by: 904svo Jul 1 2008, 01:39 PM
In my car (kit 904) it's mounted in the right front fender with 3/8 rubber hoses
feeding it. You should be able to mount it in your engine compartment with shorter
hoses to the taco plate and valve covers. It only has oil in the lines when you turn
on the pump it drains back into the engine when not in use. I used the heater lever
to turn on the pump and the hot air blower.
Doesn't this make for oil levels in the engine vary tremendously? What about using check valves in the lines to keep them full to help keep engine oiol levels consistent.
How much does this cool your oil temperatures? Maybe you should have a thermostat in the oil to control when the pump will be allowed to run.
The oil level doesn't change that much as the oil is always flowing, also the is a low
volume and pressure system. The system uses less than a 1/2 quart of oil if that much. My oil tempature drops as much as 30 degrees when in use, mine is also
set up to cool the oil in the summer with the pump on. I have over 20 ft of oil lines
in my car from the engine to the front fender.
A check valve was not installed as the engine runs better with a 1/2 quart low oil.
Posted by: davep Jul 1 2008, 02:30 PM
Has anyone looked into using a peletier device/ thermoelectric device?
I was under the impression that they produce heat/cold with low amperage requirements. This electric requirement is lower than a hair dryer type electric heater.
What is the largest alternator that we can get for a 914?
Can a stock alternator be rewound (enough room) to make a large output
Forget thermoelectric devices, I work with them every day, and I would not consider therm for use in a vehicle for either cooling or heating. First, they suck power BIG time. Second, in heat mode they are not really any more efficient than straight resistance heat but cost ten times more. Third, in cooling mode I doubt you could find the necessary room to mount a capable device, afford it, or power it.
Stock alternator is 50 amps, the biggest I have had made up is 90 amps and that is the limit of the stock housing. Try and price out a 200 amp alternator. It also will suck extra HP from the engine.
That is why the stock system works so well. Not to knock the oil cooler design , but also consider that it may slow the engine warmup time, and the engine may never get up to temperature in some situations.
Posted by: 904svo Jul 1 2008, 03:11 PM
Has anyone looked into using a peletier device/ thermoelectric device?
I was under the impression that they produce heat/cold with low amperage requirements. This electric requirement is lower than a hair dryer type electric heater.
What is the largest alternator that we can get for a 914?
Can a stock alternator be rewound (enough room) to make a large output
Forget thermoelectric devices, I work with them every day, and I would not consider therm for use in a vehicle for either cooling or heating. First, they suck power BIG time. Second, in heat mode they are not really any more efficient than straight resistance heat but cost ten times more. Third, in cooling mode I doubt you could find the necessary room to mount a capable device, afford it, or power it.
Stock alternator is 50 amps, the biggest I have had made up is 90 amps and that is the limit of the stock housing. Try and price out a 200 amp alternator. It also will suck extra HP from the engine.
That is why the stock system works so well. Not to knock the oil cooler design , but also consider that it may slow the engine warmup time, and the engine may never get up to temperature in some situations.
The oil cooler design does not slow up the warm up time, the oil is thick and the pump will move very little, what I do is wait for the temperature gauge to start moving, then turn on the pump. In cold weather the oil is pump to the head to
be heated up again and does not cool the head enought to cause any damage,
thats why I squirt the oil on the exhaust valve area. This is the hottest spot
on the head.
Posted by: davep Jul 1 2008, 04:21 PM
Good thinking on your part. I was thinking more along the line of the oil temperature not getting hot enough to boil off any condensation, thus resulting in too much water in the oil.
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