How Portable Oil Heaters Work Explained (In Simple Terms)

Oil Heater

When looking at portable heaters to keep you and your family warm when the cold starts to roll in, you may be new to space heaters, or perhaps you have never really considered getting an oil-filled space heater. But, how do they work? This may fascinate you as they do not use a fan to circulate hot air throughout the room. 

Oil-filled space heaters are just that, space heaters that are filled with oil. However, this oil is very particular. It is called diathermic oil, a special type of oil specifically made to retain heat for as long as possible.

The oil is heated up by the heater elements, making a convection current inside the heater itself. As the oil heats up, it will then heat the metal casing that holds the inside.

As you continue to read this article, it will cover many of the possible questions regarding oil-filled heaters. At the end of the article, we will also be discussing a few things. These subjects include a few of the highest-rated heaters on Amazon for you to look at so you understand what to look for when it comes to safety and bonus features.

How Do Portable Oil Heaters Work?

The way an oil-filled heater works is relatively simple. These heaters are made out of a metal casing filled with oil. Alongside the oil, the heater comes with essential utilities to make the heater function, such as buttons and a faceplate. The oil inside the space heater is what makes it function how it does.

Diathermic oil is a particular type of oil with a very high boiling point while also having an even higher smoking point. This is the opposite of your typical cooking oils like olive or canola.

While the diathermic oil has a high boiling and smoking point, it also retains heat very effectively. This means that once the oil is heated thoroughly, it will contain the heat for a long time, thus continually heating the metal casing enclosed in.

As the oil and the enclosure heat up, it creates a convection current in the room you are trying to heat up. A convection current is when any gas or water (in this case, the air in your room) and the heated air rises.

As it cools down, it falls back down where the heater is, thus completing the cycle and restarting it all over as it rises back up. This is essentially how an oil-filled space heater works and warms up the room you place it in.

Do You Have To Refill The Oil In Oil-filled Heaters?

No, you need to replace or restore the oil in your oil-filled space heater. You can’t do it.

When the heater is made, the oil is sealed inside the radiator by the manufacturer. This gives the oil no way to be refilled nor to leak out of the heater itself. 

What To Do If Oil Leaks Out

That being said, the oil can leak out if the heater is misused or stored away improperly. Hitting the heater, dropping stuff on it, or putting heavy items on top of it while being kept away can cause the weld to break or chip away.

This can cause the oil to start to leak out of the heater. Once this happens, the heater is effectively no longer able to function and can cause damage to your home if you use the heater while it leaks.

The only way to fix the issue if the heater gets a leak is to see if the heater’s manufacturer’s warranty is still viable. If it is still within the warranty period, you will have to go through a return process to ship the heater back to the manufacturer.

They will then go through an examination process to assess the damage and either repair the one you sent or send you a new or refurbished one (depending on the manufacturer). If the warranty has expired, then your only option is to dispose of the heater correctly and get a new one if you desire. 

Electric Bill

Do Oil Heaters Use A Lot Of Electricity?

No, they do not. They are one of if not the most cost-effective heaters when it comes to heating your home with a minor cost increase to your monthly electricity bill. Diathermic oil is the main contributor to this.

Because the oil is so good at retaining its heat, once the heater’s temperature gauges know that the oil is thoroughly heated, the heater will stop consuming electricity to heat the oil. It will then start to reheat the oil again when the oil starts to cool off.

When the oil is thoroughly heated, the only electricity it uses is a small amount needed to run the controls and keep the heater on. Another bonus from the oil is that the oil will still retain its heat if you turn it off.

Therefore, it will keep the metal enclosure hot, which will keep warming the room until the oil cools down enough that the heat is not effective in keeping the metal warm.

Can You Get Carbon Monoxide Poisoning From An Oil Heater?

Once again, carbon monoxide is only produced by natural gas that is not burning correctly. Most space heaters, including oil-filled radiators, convert electricity into heat in various ways.

The only type of heaters you need to worry about getting carbon monoxide poisoning from are those natural gas heaters, like propane heaters. Even then, those heaters have to have some malfunction for the gas to burn improperly. 

That being said, there are ways around this. There are plenty of signs you can look for if you think your propane heater is producing carbon monoxide.

Along with that, if you are using a propane heater inside, then you should adequately vent the room to let the water vapor and carbon dioxide out, which are both non-toxic and breathed in by us daily.

If you are or plan on using propane heaters, be sure to get and install carbon monoxide detectors throughout your home.

Although you cannot get carbon monoxide from portable oil heaters, it is still essential to go over some signs of carbon monoxide: 

  • Dizziness
  • Dull headache
  • Weakness
  • Confused behavior
  • Blurry vision
  • Nausea or vomiting
  • Shortness of breath
  • Loss of consciousness

How Long Do Oil Filled Heaters Last?

Oil-filled space heaters are among the longest-lasting heaters on the market if properly used and stored. If the proper steps are used when using your heater to keep you comfy and warm, you can expect your oil-filled heater to last upwards of 20 years before absolutely needing to be replaced. 

Making It Last Long

With that said, if you want to keep your oil heater as long as possible, there are a few things you need to keep in mind when using the heater and to store it away.

  • Tip #1: First off, when using the heater, try not to keep it in its highest setting for long periods. This can cause the diathermic oil to deteriorate faster.
  • Tip #2: Along with that, do not keep the heater on for long periods. Most come with an automatic shut-off switch if they are on for 10 or more hours at a time, in which case leave it off for an hour or wait for it to cool off before turning it back on.
  • Tip #3: If the heater you own or plan to purchase does not have an automatic shut-off switch, then try to give it brakes, and above all else, do not leave your oil space heater on 24 hours a day.

Storing Method

When properly storing the oil-filled heater during spring and summer, please put it in a closet or somewhere else in storage. Wherever you deem fit to keep it will probably be okay. However, please do not put anything on top of it or lean anything up against it.

Do your best not to knock it into or anything into the heater. This can cause leaks if the impact is hard enough. You can get away with putting some light objects like blankets on top of it, but nothing too heavy.

When you decide you need the heater again, be careful pulling it out of wherever you choose to store it and give it a good wipe down. Dust can and will gather on the heater as it is being used and stored away.

Heating that dust will cause it to be essentially baked onto the heater’s metal, which can cause the radiator to lose some of its heating effectiveness if the dust gets caked on there enough and even start fires in the right conditions.

You can, however, wrap the heater in a blanket to help reduce the dust build-up, but you should still whip it down before using it after long periods of unused.

Can You Leave An Oil Filled Heater On Overnight?

You can leave a lot of heaters on overnight. However, when it comes to oil-filled space heaters, this is one place where they work very effectively. Because oil heaters are a turn-on and forget type of heater and because the heater’s oil is non-combustible, oil-filled heaters are the least likely to start fires. 

That being said, it would be wise for you to take steps if you want to keep your heater on overnight. 

  • To start, make sure your space heater is in working order. Take note of any dings, dents, or other defects in your power cords. They can cause an electric shock, a burn, or a carbon monoxide gas leak, depending on the type of space heater used.
  • Keep combustible materials away from space heaters. Maintain a 3-foot or greater radius around your space heater. Stacks of paper, trees, sheets, and bedding should be kept away from the machine.
  • You should keep space heaters away from the bedside. Regardless of how badly you like to curl up in the sun, keep a space heater away from your bunk.
  • Purchase space heaters with overheat and tip-over protection. These safety features can help to relieve some of the stress that comes with using a space heater.

    A tip-over or tilt-over switch means that the device immediately shuts down if it is flipped over. When the temperature approaches unsafe thresholds, overheat safety senses and shuts down the machine.
  • Connect your space heater to an outlet directly. When working with an electric heater, it is not advisable to use an extension cable.

    The extension’s risks of overheating, causing electrical shock injuries, or causing fires are high and should be stopped. If you use an extension cable, make sure it is properly rated and sized for your space heater.
Oil Heater

Highly Rated Oil Filled Space Heaters You Can Look Into

This will be a small list of oil-filled space heaters you can look at if you want to purchase one for you and your family. There will be links and descriptions of each of the following.

1.  PELONIS Oil Filled Radiator

The PELONIS is our first recommendation for your overnight convenience, with a reasonable price of $79.99 on Amazon. The PELONIS oil-filled heater is available in a range of colors to complement the decor of your house.

This heater has several heating configurations for fast and effective heating in the room; it has three different heating modes (High, Low, Eco.)

This heating system has temperature settings that allow you to set your preferred temperature between 65 and 85 degrees Fahrenheit for a total affected area of 164 square feet. 

This oil radiator, intended for medium to large spaces, can offer full and constant heating without using a fan or other noisy sounds that can interfere with your sleep, work, conversation, or studying.

The PELONIS has many safety features, including an impressive 10-hour timer with remote control, meaning you don’t have to leave your comfortable bed or sofa. It also has built-in overheat security and a tip-over safety switch in case of mishaps or malfunctions with the computer.

PELONIS space heaters are lightweight and portable due to four swivel caster wheels and a robust holding handle. The heater’s cord rewind at the bottom is designed for convenience and storage.

Not to mention, the Pelonis comes with a factory warranty that guarantees that if any problems arise within the first year of purchase, the provider will repair the heater at no cost.

2. De’Longhi Oil-Filled Radiator

The De’Longhi drops in at a higher price point, with an asking price of $179.99, and is available in black or white. This heater has one of the quickest room heat-up times available, with 25% more space for air circulation and quiet operation. Not only would you be unaware of its presence, but your room would quickly heat up.

This oil-filled space heater also has several safety features, including the required tip-over security, aided by its extra-wide feet.

Another safety trait is a thermal cutoff for overheating power, which prevents fires or explosions. It also has an insulated heating system that heats the diathermic oil permanently sealed inside the heater.

The De’Longhi comes with a few exclusive features for your convenience. This involves a 24-hour programmable timer that allows you to set various times for your radiator to turn on during the day and night.

It also has an anti-freeze setting that flips the device on when the temperature falls under 44 degrees Fahrenheit.

3. TaoTronics Oil Filled Radiator

The TaoTronics comes in at a respectable $89.99. This space heater will heat a whole room equally while keeping a constant temperature.

You can set the temperature from 40 to 95°F and choose one of three heating modes: 1500W, 900W, or 600W. The intelligent ECO Mode will automatically change the room temperature and heat settings to maximize energy efficiency, potentially saving money on heating bills in the winter.

The heater has to overheat protection and passive anti-fall protection, which shuts down if it is unintentionally tipped over. The heater has four caster wheels, making it compact and convenient to travel from room to room.

This heater comes with remote control and a 24-hour timer to switch on and off automatically. You can conveniently control the heater to ensure a consistent, comfortable temperature, and an LED monitor and remote control are both available for your convenience.

Final Thoughts

Now that you have finished reading this whole article and looking at the multiple options it has provided. We hope to have provided you with all the information you were looking for, along with possibly showing you the perfect heater to keep you and your family comfy and warm in the coming months.

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Hubert Miles

I've been conducting home inspections for 17 years. I'm a licensed Home Inspector, Certified Master Inspector (CMI), and FHA 203k Consultant. I started to help people better understand the home inspection process and answer questions about homeownership and home maintenance.
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