Ideas On Auxiliary Heating Systems, Using Headers but Want Heat! |
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Ideas On Auxiliary Heating Systems, Using Headers but Want Heat! |
MikeInMunich |
Apr 20 2018, 12:15 AM
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#1
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Member Group: Members Posts: 392 Joined: 19-November 13 From: Munich, Germany Member No.: 16,674 Region Association: None |
Greetings once again from Munich!
It’s cold over here when the sun goes down, not to mention nice days in March, April, October and November. I need heat, and I don’t have it because my engine has headers. I am thinking I will need a high output alternator if I’m using only 12v in order to get the necessary output. Is this somehow a bad idea? (IMG:style_emoticons/default/idea.gif) Questions: How would a e.g. 50 amp alternator affect power and gas mileage? Would it have any effect on the electrical system? Can you recommend a heater for this application? Other suggestions on how to best get heat into the cabin without heat exchangers? Here is an article on PTC (positive thermal coefficient) heaters... https://link.springer.com/content/pdf/10.10...-11628-5_51.pdf Thanks for your feedback and advice! Mike in Munich (IMG:style_emoticons/default/smilie_flagge6.gif) |
Mblizzard |
Apr 23 2018, 02:25 PM
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#2
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
While you lose some of the instant heat, I would go with the oil as a heat source. While that can become complex an inexpensive sandwich plate with the oil routed to 2 round oil coolers small enough to fit in heater tubes. Not sure of the heater tube ID but on a quick search found the coolers down to 3-inch in diameter.3-inch PVC has Id of 3.068 inches. Oil cooler approximately $33 in cost.
Make a cap to fit the ¼-inch oil lines through and 2-1/4 inches square and 1-inch thick 12-volt fans that slides over the heater tubes. 2-fans are about $60. Of course, with a little work and flexible tubing you could use the stock fan as well. Not sure how much heat would be generated from the surface area but depending on how much could be placed inside the heater (found them in 12, 15, and 18 inch lengths) they should be capable of putting out a lot of heat. Wire the on for the fans to the heater lever via a relay and you’re done. Of course, variable speed fans would give you more control of the heat but his should be easy to do. As another option if the oil cooler won’t fit inside the tubes or you did not want to buy 2 oil coolers you could use one cooler inside a tube external to the heater tubes with flexible hoses running to each heater tube. Could also work with stock fan. |
Dave_Darling |
Apr 24 2018, 08:36 AM
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#3
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914 Idiot Group: Members Posts: 14,982 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
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Mblizzard |
Apr 24 2018, 11:51 AM
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#4
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
While you lose some of the instant heat, I would go with the oil as a heat source. Or you could go with something that costs even less and works almost exactly as well: -Nothing at all. --DD OK so I am not sure I see a connection. Are you saying you cant get sufficient heat from engine oil? Quick calculation indicates that a small oil cooler with just 1 meter of surface area could transfer almost 900 watts of heat if the oil was at 180 and the outside temp was 30F. |
Dave_Darling |
Apr 24 2018, 08:22 PM
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#5
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914 Idiot Group: Members Posts: 14,982 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
OK so I am not sure I see a connection. Are you saying you cant get sufficient heat from engine oil? Quick calculation indicates that a small oil cooler with just 1 meter of surface area could transfer almost 900 watts of heat if the oil was at 180 and the outside temp was 30F. If you have a 1-square-meter oil cooler (that's a big one!!) how long do you think it will take to get your oil to 180F when the ambient air is 30F? If you're letting the car idle, it will be somewhere between 20 minutes and never. If you're driving, I hope you've got the windshield cleared off already, but it will still take 5 or 10 minutes to get anywhere near that. So I exaggerated a little bit, but the point is that for most of us the oil-fed heater core isn't going to provide any appreciable warm air when we need it. --DD |
Mblizzard |
Apr 25 2018, 06:41 AM
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#6
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
OK so I am not sure I see a connection. Are you saying you cant get sufficient heat from engine oil? Quick calculation indicates that a small oil cooler with just 1 meter of surface area could transfer almost 900 watts of heat if the oil was at 180 and the outside temp was 30F. If you have a 1-square-meter oil cooler (that's a big one!!) how long do you think it will take to get your oil to 180F when the ambient air is 30F? If you're letting the car idle, it will be somewhere between 20 minutes and never. If you're driving, I hope you've got the windshield cleared off already, but it will still take 5 or 10 minutes to get anywhere near that. So I exaggerated a little bit, but the point is that for most of us the oil-fed heater core isn't going to provide any appreciable warm air when we need it. --DD You are correct on the delay! Not sure that I did my math correctly. I think the surface are would be about only.4SM which does bring down the potential output to about 360 watts. Going to play with the concept a bit just for fun. |
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