Here is a rough estimate of the cost to plug in the truck. A lot of people talk about the cost but have no idea what order of magnitude it is on.

750W*12hrs/night= 9kwh/night
9kwh*$.15/kwh= $1.35/night
$1.34/night*30nights/month=$40.50/month

At just over $40/month, it starts to add up. If I plugged in anytime it hit 30 degrees like many on this board suggest I would be plugging in 8 months a year which would be $325 which is a significant sum of money. It is hard to calculate your fuel savings from running your block heater but it is unlikely to exceed this number.

The message from these numbers is that it is expensive and very wasteful of energy to run the block heater when it isn't necessary. It is a great thing when it is appropriate. If you run it, please get a good heavy duty timer or thermostat and actually use it.

 

325 would be worth the wear and tear on batteries, alternators,etc that i save just by plugging in. not to mention how much easier it is on the motor, also the heat and faster warm-up times, and just the satisfaction that the motor is semi warm and not ice cold when i pull out and start driving. Also, i don't know that many people around here who plug in for 12 hours per night......the earliest i plug mine in is around 11 and it is unplugged and cranked by 6:30....i know 8 hours isn't much less than 12, but over the course of 8 months it would be.....however i only plug in maybe 3-4 months out of the year just when it gets below 30 usually...JMO

 

15¢/kWh is on the very high side of power rates.
National average is 10¢ = 7.5¢ per hour = $1.80 per day = $54/ month @24/7
My power rate is 3¢/kWh = $16.20/month, well worth it for me plugging in 24/7 for extended engine and component life.

 

i thought that $40.50 seemed pretty high, i guess thats possible in some areas. i dont notice too much of a difference in my electric bill. i keep mine plugged in simply for the faster warm up times. leaving it pluged in will not hurt the truck, it might wear out the heating element in the block heater faster but my 96 still is on the original one since it (the truck) was new, and it was a MN truck before i moved down here.

 

I did 12 hours per night because I was trying to show the effects of not using a timer. If you have the timer set to 3 hours, then you divide that number by 4 to get something under $10 per month which is much more reasonable.

As far as electric rates go, we must be getting ripped off around here. The published rate is lower but by the time they charge you transmission fees, it is almost $.15 per kwh.

Anyways, I hope you guys understood the point so we all at least understand the order of magnitude that the cost is. It isn't thousands of dollars but it isn't pennies. A timer will make a world of difference in the long run.

 

Wow! I guess I am the only one to replace a block heater element. Actually I have done 2 over the course of 290,000 miles. Cheap $35.00 thru Cummins. I also have a grid heater on the engine oil pan and one on the trans. Start it and drive away. The Dodge loves it, probably thinks its in the Bahamas instead of Alaska. I plug in below 40F and give it very little warm up time.

 

Do the block heaters have a built in thermostat so they cycle on & off or do they just stay on? It seems like a 750 watt heater staying on all night would overheat the coolant?
MW

 

No stat, they stay on. Coolant circulates by convection (hot rises) throughout the entire system keeping it from overheating. It even circulates though the heater core.

A friend added on a canister type 1200 watt heater and it would overheat his coolant if left on for more than four hours.
Indicates to me that Cummins chioce of 750 watts was well thought out.

 

I know San Juan Road too. I have a friend that lives on Murphy Hill Road. Her car broke down and I used my 97 Ram CTD to tow it to my house in Santa Cruz last week. I may have passed you and not known it.

Like others have said if you want heat in teh cab faster plug it in. I haven't plugged mine in since I got it two years ago. Besides, I grew up in Illinois and it doesn't get cold in Santa Cruz. When I fire it up in the morning it is cold for about a block then it warms up and drives normal again.

 

The grids come on when below 20C, or 68F. Thats a warm summer night for me.

I used to plug in back when it would get to -10C, and I would plug it in all night. No issues whatsoever.

 

hmm maybe haha
do pass by here alot because i live off of san juan and aromas rd and every once in a while i hear a twelve valve straight piped truck down the road

 

A lot of people quote the 40°F threshold, but have no idea why this magical number.
Once an engine block hits 40° & lower the cold friction from the rings increases exponentially as the temperature lowers. From 70° to 40°, friction increases, but not as significant as the threshold.

The 9¢/kwh average is just that, average. If they used median it would probably be closer to 15¢/kwh. Average is based on the number of ultilities. Median is based on the number of people.
Rates actually go from a nice subsidized low of under 3¢/kwh to Eastern seaboard areas with rates over 20¢/kwh

On a cold start my grid heaters do not come on until the temps are in the 40's. All trucks react a bit different to temperature.

You can use any cheap appliance timer to turn on your grid heaters. Just don't use it to turn them off. The contacts fry from the arc snap.

Here's my formula for the block heater on all my vehicles
If air temps are 30° to 40°, I run the block heater 1 hour.
20°-30°, 2 hours
10°-20°, 3 hours
+0° - 10°, 4 hours
-10°- -0°, 5 hours
Anything colder and they run all night which is 6-10 hours depending on the wind, last time I drive it and the daily highs and lows.

On those colds days away from a current bush (plug in) the Espar is a lifesaver for the truck. Be really nice to have a gas powered on the mommy van