From reading all the block heater threads over time some how was drilled in my head heavy duty timer or don't do it. So on the hunt at Home Depot today was looking for one without luck. Got to ordering my 1 7/8 hole saw here on Amazon right now for the Marinco upgrades I'm waiting to do & searched heavy duty timer also. Im finding all 15 amp ones. I have a dozen of those timers in the garage for Christmas lights. Is 15 amps sufficient for the block heater?

 

If I remember right, the heater is 8.8 amps. No more than 10 amps.

I'm not a person that would know for sure, but seems like it should handle it.

 

I think you are right. I have 9 amps here in my notes. Maybe other members meant the 15 amp being heavy duty.

 

As many times as I try to rep you its always telling me I gotta spread the love elsewhere!

 

We don't spread the love around as much as we should, I just tried to rep you for the thought, you guessed it, Gotta spread some more around! Thanks though, after all, it's the thought that counts!

 

LOL, yes the thought is everything!

 

I'm thinking that since your circut breaker is probably only 15 amps on the circut you'll be plugging into, a 15 amp timer should be just fine.

 

Here is the one I use:

I have it on a GFCI circuit on a 15A breaker.
Have had it about a year and a half, no probs.

But as of yesterday, I have a short somewhere and I was wondering if anyone has ever heard of the heater itself, shorting out.
I have a Marinco setup, when connected to the heater, it shows shorted. When I unplug it from the heater, the line is good.

Would appreciate any input!!

 

F350,

I am not familiar with Marinco set-up, and just throwing out an idea with this one. You don't have an extra ground thrown in there do you? Only reason I ask is cause you said when plugged in there is a short, but when unplugged there isn't. Did you just install the Marinco, or has it also been working well for the past year?

 

The Marinco is basically the same as OEM (I think), they just have some other customizable mounting options, with longer cords.

I have had it working for at least a year and half now, same power cord, same GFCI. Nothing else trips that circuit. Even tied another power cord, still tripped, thats when I started tracing it out on the truck.

 

Ok further follow up. Just tried a new extension cord, as well as another new block heater cord, tripped the outlet immediately... sigh....

 

If you use a 15A rated timer, it will handle the element just fine. The reason folks may have drilled "use a timer, or don't do it" is because after three hours...the block heater has reached a point that there isn't much to gain leaving it in longer. You can live it plugged in for days if you want, just spinning the electric meter a little quicker while it's plugged in.I'm not saying it never happens, but it's not a common failure. The cord on the other hand...they seem to be the weak point on the block heater circuit. Truth be-told, that's how I'd want it if I was designing a diesel engine.When you say new cord...are you plugging it directly into the element above the starter? If yours has failed, that would be something only the 2nd or 3rd one I've ever heard about in almost 5 years.

 

Have you tried ohming out the cord & heating element yet to see exactly where your problem is? Also, is a GFI outlet preferred?

 

Well, it's an outside outlet, so that's why I have it on a GFI.
I have Christmas lights and stuff plugged in and outdoor lighting on the same circuit, but they have been on for awhile, same last year. Even if I unplug everything else it immediately trips.
I have about 15 ohms, with no power plugged in.
I guess my next test will be to just plug it into another circuit.

 

Resistive loads are extra hard on everything (buss bar,breaker,wire,out let,screw connections,scotch loc conections,extension cord,timer,and especialy GFI devices) in that circuit. Most anything electrical has information printed on it conceurning type load it is rated for. Even when resistive load is below rating,you will experience many more failures compared to circuits with inductive and capacitive loads. Beyound the obiviouse challanges this presents,the most important imo is that risk of fire is multiplied several times over. My apoligies for bringing up the subject but the fact the block heater is in use mainly while we sleep and often in an attached garage demands no compermises be made. I highly reccomend getting someone knowledgable help set it up if you "don't understand all you know about it". At minium put a smoke alarm that is loud enough to wake the dead in the garage.