Not true. The amperage will go down as the voltage goes down, but not quite as much due to the nature of the heating element (it's resistance increases with temparature). The heater will get hotter (more wattage and current) at 130 V than at 110 V. As you add more wire or use smaller wire, a larger percentage of the power is dissipated in the wire than in the heater *and* the total power dissapated by the wire plus the heater will go down.

As Dave pointed out, you want the power to the heater, not the wire, so use the shortest and biggest wire that's practical. Also, make sure all connections are clean, tight, and protected from the weather as much as possible. If possible a GFCI breaker or outlet is a good idea just in case you do something silly early some cold, dark, and damp morning before all brain cells are firing...

 

Sooooo, 11 months later I plug in my block heater for the first time since I bought my ride. I decided to see what kind of neat things folks have done with their heater set up and searched 'block heaters'.

It was nice reading not to coil the plug up, reading that sent me running out the house to the car-port and uncoiling the damn cord.

 

Talk about an older thread. But it all still applies for this years very cold weather we are having here. 15 degrees this AM.

 

Just searched and found this thread. Good advice here. I'm getting a Kats 1500 watt for Christmas!

 

My block heater appears to to work so I bought a hot air gun for $15 from HF. I mounted it to a piece of plywwod point up. I will point it aiming at the oil pan. Two setting 1000 degrees F and 475 F.

Night temps in NJ not cooperating its 50 degrees every night!

 

I agree with Dave in regards to cord sizing, however in the real world a saw only runs for a few seconds, a block heater is on constantly and just sizing up on the cord when you have an increased amperage draw is another can of worms to open.
Typically if you were drawing more than 15 amps you would need to have a larger breaker as well and also be sure that the wiring to the receptacle was sized accordingly as well. you can't just put a bigger breaker in.
I live in one of the coldest parts of north america and with my GPs working well my trucks NEVER need to be plugged in.
Always use the shortest cord possible, be sure the circuit can handle the load, and put a block heater timer on the whole setup, it will warm an engine up in 90 minutes.

 

Just got me 50' of 12 gauge and a timer. Just waiting on Dec 25th to roll around and I'll have the heater

 

You should be in good shape and saving money on electricity.
Good luck.

 

x2^^^^. was gp condition and fuel system condition ever questioned back in 2007 when this thread started? if eveything is working right then you should not need the block heater at all. i use mine when the temps get below 50*F. helps with cab heat and gets oil pressure up faster. mine is on a timer as well.

 

It's not about your local climatic averages, but what your real temps & wind have been for the previous 12 hours or so. At these extremes you must measure your local conditions. Back when I had to start my diesel, when it was new, at 0600 after a day when it never got above -10°F and a night when it got down to -25°F, I believe it really needed to be plugged in for about 3 hours - I did not care to strain my starter & other components by skimping on things like extension cords and electrical power.
On one such bitter cold night, the insulation on my heavy duty electric cord SHATTERED when I was unrolling it. After that I bought a cord with a reputation for resistance of super cold, didn't coil it much if at all, and left it plugged in all night - to keep the cord warm!
The prewarmed coolant also helped the defroster defog the windshield right away, else my breath would generate ice on the inside of the windshield if I closed the windows, something I generally do at -25°F.

 

Timer is a good idea if you are sure you won't need to start earlier than scheduled. On the other hand if you might need to start at any time of the day or night for safety or business reasons, you might dispense with the timer.
Also suggest some kind of indicator light where your power cord to the block heater is connected to verify that the circuit is live and has not malfunctioned. You should be able to look out your window & from a distance see that little light verifying the power is going into your block heater. Years back my circuit malfunctioned & cut the power in the middle of the night, resulting in a stone cold engine block just when I wanted to start up & go to work. It was one of those -25°F mornings I have referred to. I was a little late that day.

 

after a day when it never got above -10°F and a night when it got down to -25°F,


I don't know where you live but -25 is mild here.
It can and will be -40 here in winter.
Last year we had 38 days when it never went over -25 day or night, always starts first try, your not driving a Chev are you?

 

Nope, I was referring to the very first winter after I bought my 1983 Ford diesel NEW, everything on it was in tip-top condition at the time & having that thing start whenever I wanted was an obligation to me - I lost income if I showed up late.

 

So you're the one they wrote this song about!

 

I hate winter yet I live in one of the coldest places a man could be in unless he goes to Northwestern Canada.
Pretty nice most times though, thing of it is, electricity is very expensive here so we have to manage our usage.
keep the trucks running good so they don't let you down, same as you, can't miss work.