3 Best Oil Heaters You Can Leave on All Night

Oil heaters are exactly the type of heater you need to leave on all night and heat your basement safely.

These days, nights are freezing cold and you absolutely need to stay warm at night in order to get a good night of sleep.

For heating a bedroom, oil-heaters are really practical: Compared to other space heaters, they are very safe. And they are energy efficient and won’t raise your electric bill too high.

In this article, I’m going to show you three different oil-filled heaters you can leave on all night without any worries.

Because you might be insecure about running a space heater overnight, I’ll also show you why oil-filled radiators are safe to run all night and what you can do to increase safety even more.

Let’s take a look!

3 Best Oil Heaters you can leave on all night – My picks

First off, here are the 3 best oil heaters you can safely leave on all night:

  • Pelonis 2019 Oil Filled Radiator (click here to check the price on amazon) – The Pelonis oil-filled heater is one of my all-time-favorite heaters. It comes with an incredible amount of features like a built-in timer, a remote control, a thermostat (and much more). Compared to other heater brands, Pelonis is the most affordable! I don’t know where else you can get such a heater for that price.
    Additionally, the Pelonis heater is ETL certified which makes it a safe choice for running overnight.
  • De’Longhi Comfort Oil-Filled Radiator Space Heater (click here to check the price on amazon) – This heater is a good choice for bigger rooms because it can produce so much heat safely. So, if your bedroom is big and you want to keep cozy & warm, this DeLonghi heater is your choice. Just like the other heater, it comes with all the safety features like tip-over protection, a timer, and overheat protection.
  • BEST CHOICE: DeLonghi TRD40615E Oil-Filled Radiator Space Heater (click here to check the price on amazon) – Okay, as you can tell, I’m a fan of this brand. They produce solid and high-quality heaters for low prices and get tons of good reviews. This model is a little higher priced than the previous model, because the heating times are programmable. I would trust this heater to keep big living rooms warm. It also has an even better rating than the previous heaters.
    The steel cover protects it from damage when it tips over and adds a lot to the overall design. A good choice if you don’t want to have an ugly heater in your bedroom.

Safety features that keep oil heater safe overnight

Somewhere I once saw a question posted online:

“Why are all space heaters so ugly?”

It made me laugh! I never thought about that. So, if you want to pick a good looking heater, that you can leave in your bedroom without worrying that someone says it’s ugly, I’d suggest the last heater from the list.

Anyways, this article is not about beauty, but about safety and leaving oil heaters on all night.

All of the oil heaters I selected have the following safety features:

  1. Overheat protection
  2. Tip-over protection
  3. Thermostat
  4. A timer to automatically shut off

The Pelonis oil heaters are even ETL certified (That’s a solid safety certification – not all heaters have it)!

Oil-filled heaters are the safest type of heaters

By choosing one of the above oil heaters, you can be sure to have a safe way to heat throughout the night.

But why are oil-filled heaters the safest types of heaters?

First, the heating element of an oil-heater is encased in a metal body and encased in oil.

The metal body and the oil, therefore cover the heating element and make it impossible to touch it.

Most space heater accidents are caused by space heaters with exposed heating elements that get hot enough to burn things.

Because oil-filled space heaters distribute the heat over a big surface, everything stays safe to touch.

Additionally, oil-filled heaters don’t use any burning fuels like propane or diesel to produce the heat. Instead, they rely on plain electricity that in turn heats a heating element which in turn heats the oil inside the heater (I hope this didn’t confuse you).

The oil in oil heaters is very safe for heating

The oil in oil heaters does two things:

  1. It stores heat – Meaning that it heats up slowly and cools down slowly as well. Oil heaters are rather slow heaters because the heating element first needs to heat the oil.
  2. It keeps internal pressure stable – Engineers decided to use oil in heaters because it has a high boiling point. The oil stays liquid while it’s heating and doesn’t really increase the pressure on the metal case.
    If you replaced the oil with water, for example, your heater would be a lot more likely to explode because water evaporates and builds pressure.

The combination of metal and oil that can handle high temperatures is a very secure combination.

“So when I say that oil has a higher boiling point than water, what I am actually saying is that the chemical bonds that hold oil together are stronger than the ones holding water together – it takes more heat to break them apart.”

Department of Physics – University of Illinois

Nearly all modern oil-filled heaters (like the ones I recommended above) have a vast amount of security features. You get everything you need to leave them on all night.

For example, oil-filled heaters have built-in tip-over protection that shuts them off automatically as soon as someone tips them over (can happen in the dark at night).

I’ve also written an article about heaters you can leave unattended. My favorites were by far the oil-filled heaters.

Even though oil heaters are very safe to leave on all night, here are some additional safety measures you can take.

What to make sure before leaving an oil-heater on all night?

You don’t feel comfortable leaving your oil-heater on overnight? Don’t worry, I know how you feel.

Because I was in the same situation with my heaters, I took some safety measures to make sure that no accidents happen and that I can sleep calmly.

First, don’t have any flammable objects nearby – Avoid having clothes next to the oil heater (even worse: don’t dry clothes on your oil-heater overnight – it might work, but for the night, let’s avoid even the slightest risk). This includes all kinds of fabrics. Also, avoid having your fluffy slippers next to the heater.

Because heater accidents always happen when the heater is drawing too much power from your outlet (and thus the cord overheats and catches fire), consider using low power settings throughout the night. Even on low power settings, oil heaters get hot enough anyway.

The less power you use and the smaller the temperature you set, the safer your cord will be. 

When you sleep, you don’t need to heat all night. Mostly it’s enough to fall asleep while it’s warm. Therefore, consider setting a timer that automatically switches off your oil-heater in the middle of the night.

To do so, you can either use an electrical timer switch or use a space heater with a built-in timer (all of the oil heaters I recommended above have built-in timers).

Don’t worry!

It will not get too cold during the night, because oil heaters retain their heat.

Can you leave an oil heater on overnight?

Answer: Yes, you can leave an oil heater on overnight. Oil heaters are designed to be very safe. In contrast to other types of heaters, they don’t expose any heating elements, their big metal surface doesn’t get too hot to the touch, and oil heaters have lots of additional security features like built-in timers, tip-over protection, etc.

Oil heaters are a lot less likely to cause you any trouble when you leave them on overnight.

The internal pressure of the oil stays constant because the oil has a high boiling point. Therefore oil heaters can handle high temperatures for long times.

Also, there are no moving parts that cause noise and sleep interruption. And the hot body doesn’t get glowing red like infrared heaters.

That’s why oil heaters are the best heaters for sleeping.

Other ways to keep warm at night

“If your bedroom gets too cold in the later part of the night, consider investing in a hot water bottle or two to put under the covers 20-30 minutes before you climb in.”

verlo.com – Sleeping with Space Heaters

With a hot water bottle, you can easily avoid the need for a space heater running all night.

You can preheat your basement with a heater and then turn it off when you go to sleep.

To stay warm, simply use a hot water bottle.

While this works great as long as you’re alone in the room, a water bottle wouldn’t work for 2 or more persons.

hot water bottle to replace leaving an oil heater on all night

Conclusion – Best Oil Heaters you can Leave on All Night

Personally, I’d use the Pelonis oil heater (click here for amazon link) to heat my room overnight.


Because it gives you the most bang for your buck.

You get everything you need – from all kinds of protection features up to a safety certificate and high user ratings – for a lower price than the DeLonghi brand models.

If I was you I’d pick the DeLonghi models if you want a nicer and more luxurious design, or if you want to heat a bigger room.

But don’t worry. All of the heaters do a perfect job of heating a room all night.

Attributions: takuhitofujita (title image)