Use one of those Webasto systems.

http://www.webastoshowroom.com/images/truck_trifold.pdf

It doesn't use much fuel and doesn't draw much from the battery, plus you can program it to preheat your truck just before your trip.

Webasto or Espar is the ticket. I know the Espar unit is 5000 watts as opposed to 1500 watts of your plug in. The coolant also gets circulated. It only needs to run for about 2 hours even on the coldest nights, and you have heat as soon as you start the motor.

Originally Posted by sdc49

I have detriot engine and was wondering if a could hook up my 1500 watt converter to batteries and use a extension cord to the engine heater during winter nights, to keep it warm. I am worried about baterries being dead in the morning, truck is run everyday, or could I install extra batteries and have the truck alternator recharge them during the day. Will the alternator charge more than the four normal batteries the truck has. Any ideas.

You may want to consider placing a battery charger next to your parking spot, connect the clamps to your batteries as part of your post trip procedures, put the charger on a timer or a switched outlet that you can turn on just before you head out. or.......

Originally Posted by MNdriver

Recipe for disaster there. No power to turn the starter.

?

Follow the sage advice below and purchase an APU which is not cheap... $8,000 and you install it... and you should probably do a cost analysis... engine idling at 1 gph vs. APU at .25 gph... to see if it's at all worth it for the 6 or so months needed.

Originally Posted by allan5oh

Webasto or Espar is the ticket. I know the Espar unit is 5000 watts as opposed to 1500 watts of your plug in. The coolant also gets circulated. It only needs to run for about 2 hours even on the coldest nights, and you have heat as soon as you start the motor.

Adding batteries only increases work for the alternator which may shorten the life of said unit.

Really it is a good idea to put transformer in frame box to charge batteries. Use stabilized converters only to prevent overvoltage. for stand by 12.7-13 V recomended. To charge batteries use not more then 14.8 V and not more 20 A per battery current.

Some drivers here have battery chargers in truck.

It is not kidding, but there are truck heating service in Russia to warm up, charge and start frozen truck

some commercial
http://www.youtube.com/watch?v=MxYW0...eature=related

For starters plug in block heaters that are designed for 120V power (from your INverter) will use enough power to drain your batteries enough so you wont be able to start the truck anyway.

The webasto system is probably the best for the money. They make an engine block heater unit and it does a good job. You only need an engine heater actually on for maybe 2 hours max before you are going to fire it up. I have only ever needed it a few days a year in the cold of Edmonton, AB. We are talking -30 at high noon. Also the webasto 2000ST does more than enough for bunk heat and burns like 0.2 gallons for 10 hours. It draws very little current from the battery. Well worth the money. You don't want to get the bigger bunk heater, you will turn it up to like 5% power and it will build soot and you will have problems. The bigger webasto unit is used for heating 24' box trucks. I would not advise using the batteries for very much at all in winter time when the engine is off. If it is so cold you fear the block will freeze, if you don't have an outside charging system, apu or plug in, better to leave it running.

A block heater run off a 1500 watt inverter, you'd might as well stand there with a cigarette lighter under the block to keep it warm.