Tech Talk: Block Heaters

Do I even need a block heater?

Answering this question is a good place to start a discussion about block heaters and their uses. To help explain their purpose, I want you to think of the process of baking something in the oven, before you even put the food in the oven you first turn the oven on to preheat in order to get the best end result for your food as possible. Going a step further with the visualizations - many of us in some way preheat our own bodies for the day ahead, whether it be through drinking coffee, eating breakfast, or doing morning stretches. So why should we expect any commercial vehicle to not need to be "preheated", or prepped, for the day as well before we start using it to pull heavy loads down the road? 

Here in the Midwest, we are the fortunate ones who get to deal with extremely cold temperatures. When we have those cold snaps that get into the -10°F temperature range for a high, most of us don’t want anything to do with going outside. Yet we ask our vehicles to sit out there and start right away when we demand it. It behooves us to do what we can to ensure they start with as little stress as possible. When temperatures get extreme, these vehicles can keep us safe from the freeze. The more we can do to ensure the proper operation of equipment, the safer we and our drivers will be. 

So, what is a block heater?

A block heater is an add-on truck part that essentially does what the name entails, which is heating a truck’s engine by heating the cooling system, thus heating the entirety of the block. When outdoor temperatures get cold, the oil in the engine begins to stiffen up and is unable to efficiently reach all the engine parts it needs to lubricate. Along with not reaching all parts, the thickening oil is also unable to provide the correct amount of viscosity to properly lubricate. This can potentially cause damage to critical components. Oil in the cold can be equated to cooking up some bacon in a frying pan. At warm and hot temperatures, the grease flows and is liquid, but later when you let the bacon grease sit, then it starts to gel up, which is a representation of what engine oil does in extreme cold. 

When should I plug in a block heater?

Although there is not a hard and fast answer to this, a good rule of thumb is that if the temperature outside is going to be below 5°F, then you may want to consider plugging in your heater. Essentially the main thing to remember is that if it is going to be extremely cold, then you will want to plug your vehicle in. 

How long should I leave a block heater plugged in for? 

Having come from an area in the deep south, I previously had a limited need for block heaters myself and therefore had to do some research to get myself up to speed. I have noticed some tractors regularly being plugged into a block heater overnight, however, my research has led me to believe this is an inefficient use of electricity. 4 hours is considered to be the maximum amount of time needed for a block heater to be plugged in. This should give you the maximum advantage and cost savings from your block heater. I do understand though that it can be hard to get up and out to your tractor to plug it in 4 hours before use, but to save some money this may be a new step to add into your daily routine. 

How can I use a block heater efficiently to get the most “bang for my buck”?

As mentioned previously, keep the cords in good working condition, as they are often outside fighting the elements while also being dropped in the snow, ice, and water. If you choose to go with using a timer, instead of manually plugging in your truck, you will want to ensure that you also use a timer that can handle the high-power draw as well. This is no place to skimp and save a dollar. Many of us have at some time or another seen a tractor burn down with no one around. This may not have happened due to a block heater or cable, but it is certainly something that could happen if the right tools aren’t used. So why risk the chance of it happening to your unit when it could easily be prevented? 

Stay safe out there. I’ve spent a night up on Wolf Creek Pass due to its closing after I got through and watched many vehicles slide out right beside the recovery vehicle I was in. Remember- think the best, but always prepare for the worst.