Crazy question/idea, Sometimes while driving my Jeep to work on cold months (which is from Oct through Feb here), or when I have to park far in my apartment complex, I don't always have access to an electrical outlet to use my engine block heater no matter how far I stretch the extension cord. I was wondering if anyone knew how much power it exactly draws, as I was considering hooking my engine block heater up to a power small power inverter and to a switch located inside my cab, so I could switch on the engine blocker heater to run off my Jeeps Battery to keep my engine warm. I am aware that this will significantly decrease this battery daily if not kill it daily, and I would run a 2-battery set-up with some type of battery management hardware, but my question I guess (as I am far from mechanic status) is how long could I run the engine block heater off of one battery before the battery would die completely?? Should I tie the two batteries together for longer times, and more even charging? For example, would I be able to power the engine block heater for 8 hours, 10 or 12 hours on battery? Also would my heavy duty alertnator, be able to charge a completely dead battery like that on a daily basis and still keep my primary charged as well? This seems crazy, I know, but just curious if anyone had some hard numbers they could run or spit out to tell me if this would work for me. Yes, Garages are great, but neither my apartments or job provide me with one. Any help, ideas, thoughts, comments, or rantings are appreciated as usual, but would appreciate numbers if anyone seriously has them as far as amps draw, and other. Thanks.

i don't know the answer to your question. maybe if we knew the amps draw per hour on the heater, a guesstamate could be formulated.

i tried runing an eletric blanket off a car battery for camping and on the lowest setting it killed the battery to "0" volts in 20 mins.



larrygo

You're in Jersey and need a engine block heater? I don't think I get that, I've lived in much colder places and the only engines that ever had block heaters were diesel flavored...and only during below freezing.

Seriously, do you live in a wierd part of NJ that is subzero in the winter? The average lowest temperature is only 15degrees F, not that bad. Sure, its nice to have a partly warmed engine, but I can't imagine how it is necessary.

You'd get more out of synthetic fluids. Those don't require the amps. Your dual batteries will both be dead by morning. Electic resistance heat is pretty inefficient. Keeping the vehicle in a top state of tune will also help pretty much. I just can't imagine the need that far south. If you lived at the top of Maine, Michigan, etc, you might have a reason. If your battery is already dying, just replace it at the beginning of winter. It should last at least 3 or 4 winters.

Thanks to all for the replies, I appreciate all the replies and do listen. NO not a weird part of Jersey, but Jersey does get cold, often going down below zero at times with heavy snow (at least it was last year) for about 4 months through the year (Nov - Mar). I also travel a bunch up to PA (as my parents live there, and I have just purchased property there as well), as well as new england states on occasssion. Where my parents live in the poconos, yes it does get cold, and they get alot of snow up there. I see the engine block heaters as an advantage regardless of what state you live in, and not just a fancy option as do some people. If you get down into the teens, I feel it is better for the engine to have one, instead of cold starting it at those temperatures. I was mearly asking to see if anyone had any cold weather concerns, ideas, or stories of things that might have worked for them that I could incorporate into my Jeep (as mentioned since I don't own a garage). At the very least it couldn't hurt, right? I am trying to set my Jeep up for winter wheeling the best I can, but have found scant articles about tech on this subject. I also wouldn't mind hearing from anyone who has information on snow wheeling and what works good as far as set-ups. I appreciate all the commments, Thanks, and Happy Trails!!

I own and drive a semi The only time I plug in the block heater is if it's in the teens again it's a diesel. However I live in Iowa and it gets below 0 for weeks on end in the winter and none of my gas engines have block heaters and they all start just fine. But back to your question. The block heater on my semi runs about 1500 watts so the inverter that you would need would have to be a minimum of 1750 and with the ampress that the heater would draw I don't think the battery even in a dual bat. setup would last even an hour. Besides batteries are not designed to take a full discharge every night. You'd be replacing your entire charging system before too long.
As for snow wheeling it makes the easy trails quite interesting.

8amps at 110 volts..block heaters drain power fast...the parkage I park in..only have their outlets on for an 15 mins every hour...if not less

I live in edmonton alberta thou...and 3 weeks ago it was -40 lol...so we gota plug them in..or it wont start. That was a fun day...had to start the car about 10 times before it would stay on...block heater was also plugged in all night..