What Is RV Antifreeze?

RVs rely on water lines to move water through the system. If the lines or pipes become frozen during winter, they can crack.

At this point, not only will they leak internally once the ice has thawed out, but they’re extremely difficult and expensive to access and get repaired too. Especially during winter!

What is RV antifreeze? RV antifreeze is specially formulated to protect the water lines without causing damage to the pipes, seals, or other internals. It replaces existing water inside an RV’s plumbing system during winter to prevent it from freezing and causing the lines to split open.

Propylene glycol is the preferred ingredient over ethanol-based formulations, a blend of the two, or recycled antifreeze products.

We explain more fully what RV antifreeze is, how it differs from automotive antifreeze and more.

RV Antifreeze

Our articles on RV antifreeze selection, suggested use, and safe disposal:

Is RV Antifreeze Toxic to Animals?

Will RV Antifreeze Kill Grass?

Does RV Antifreeze Freeze?

Will RV Antifreeze Thaw Frozen Pipes?

What is RV Antifreeze?

RV antifreeze is a solution that is purchased to complete the winterizing process necessary to protect your RV throughout the winter.

Splash 619526 RV/Marine Antifreeze – Pink (6 gallons)

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It is a synthetic substance that remains liquid even at the usual freezing point. This is beneficial to an RV’s plumbing systems to prevent water pipes from becoming frozen and cracking.

The antifreeze liquid is added to the water system throughout the motorhome or trailer once the pipes or lines have been cleared of water. It’s pretty clever.

What the chemical can do is lower the natural freezing point to prevent ice from forming blocking up water lines and causing other issues. So, your RV’s water pipes won’t freeze.

When Should You Use It?

What is RV Antifreeze

Certainly, using it in the winter makes sense but you don’t need to wait that long.

If you live in an area where you get extended colder seasons, it might be sensible to add RV antifreeze earlier and/or to repeat the process if the colder weather extends into the new year too.

How Much Antifreeze is Usually Needed?

For an RV, 4-6 gallons are commonly required. It depends on the size of the RV as to how many gallons are necessary but it’s certainly not one or 2.

Bear in mind that the chemical must be run through the water lines to all the kitchen and bathroom faucets, all parts of the shower system (faucets and showerhead), and the toilet too.

Some antifreeze should even be left in the toilet bowl after flushing too.

Campers and trailers are smaller, so usually just 1-2 gallons of RV antifreeze is required to complete the task.

Difference Between RV Antifreeze and Automotive Antifreeze

The composition of the automotive antifreeze is hugely different from the RV antifreeze. Whilst they do essentially perform the same function, there are other factors at play here.

Cars and Trucks

With a car or truck, the water pipes are only for things like keeping the engine cooled.

Applying automotive antifreeze aims to prevent the pipes from becoming brittle and cracking. This could cause water to not reach the engine (they run extremely hot even in colder temperatures).

However, the water system is never used as a source of drinking water, water to bathe with, to keep the shower flowing, or to flush a toilet.

Because of this, there’s less concern about how toxic it might be.  

Motorhomes and Campers (RVs)

With a motorhome or camper, the RV plumbing system is present to provide ample water wherever it’s needed.

Therefore, any antifreeze must not damage the internal water pipes and is not non-toxic to humans.

Because of this, there are RV antifreeze products and automobile antifreeze products to use with other vehicles.

It’s critically important to note the difference.

Can RV Antifreeze Freeze?

Contrary to what you may have heard, RV antifreeze can change its consistency when battling extremely cold weather.

Read Also: Does RV Antifreeze Freeze?

RV Antifreeze Types – Know the Differences

Not only is RV antifreeze completely separate from automotive antifreeze, but there are at least four antifreeze types intended for RVs.

1. Recycled Antifreeze

It’s possible to recycle antifreeze – believe it or not – when a considerable amount of it is used.

This is the case in the airline industry with jets flying through colder-than-cold conditions and must ensure their systems don’t freeze up, including their water pipes.

Some of the antifreeze used at airports is collected, recycled, and resold in the consumer market.

Often in smaller stores at discount prices. People look for a bargain and find the wrong type of product as a result.

Therefore, it’s necessary to keep an eye out to avoid this type.

It’s not great for your RV’s delicate plumbing systems and is likely to be harmful to humans (or, at least, unpredictable in this regard) because both the composition and purity are unclear.

2. Ethanol-based

An ethanol-based RV antifreeze is commonly sold and found in many places.

It’s grain alcohol.

While it’s an attractive pink shade and will duly lift the freezing point of water, there are added risks of damaging the pipes or seals in your RV.

It’s also less than palatable if you have not fully flushed your system out in the new year.

This is best avoided for a variety of reasons even though it can be the less pricey option. It’s not as bad an idea as the recycled kind, but there’s at least one better alternative.

3. Ethanol and Propylene Glycol Blend

The RV antifreeze that mixes ethanol with propylene glycol trying to take the two most useful substances for protecting your RV from the cold – double as powerful, right?


While the inclusion of propylene glycol is welcomed, the greater the amount of ethanol in the mix, the more potentially corrosive it could be in your RV’s plumbing systems.

It’s just not worth taking the risk.

4. Propylene Glycol

Propylene Glycol is by far the best RV antifreeze to use. It’s more expensive, but it’s the right choice. Also, it’s the only reliably alcohol-free RV antifreeze too.

Splash 619526 RV/Marine Antifreeze – Pink (6 gallons)

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It helps your plumbing perform better, isn’t corrosive, and protects it in freezing conditions too.

It’s also a lot safer compared to the other alternatives.  

Does RV Antifreeze Go Bad?

Most high-quality RV antifreeze brands will last at least 2 years and perhaps 5 years at most.

Some may be affected by whether you’ve already opened the gallon bottle yet to partially use it or left it untouched.

Look at the product’s label. There should be an expiry date on there.

Alternatively, check the manufacturer’s website for information about the lifespan of their products.

Another way is to attempt to freeze it and wait to see how it reacts. If it freezes up, then it should be replaced for sure.

Can You Reuse RV Antifreeze?

Technically, nontoxic RV antifreeze could be reused. However, we do not recommend it.

When it has already been run through an RV’s plumbing, it will collect water residue, loose plastic particles, and other plumbing debris. Collectively, these will alter its composition making it less reliable.

What Color is RV Antifreeze? Is Pink RV Antifreeze Toxic?

For the most part, antifreeze solutions are pink in color. Typically, they’re good to use up to -50F but do check the specific product to confirm this.

There’s also the occasional blue-hued type too. This is far less common and often can handle even colder temperatures up to -100F.

This might be the right kind if you’ll be traveling up to Alaska.

Is RV Antifreeze Safe?

RV antifreeze is safe to use for its intended purpose — namely to prepare the internal plumbing inside a recreational vehicle for colder temperatures, or the winter season.

Care should be taken with the substance around plants, animals, or other people.

Is RV Antifreeze Toxic to Pets?

For the same reasons that it’s not good to consume any of it when mixed into the water supply, equally, it’s not good for pets either.

It’s true that, unlike automobile antifreeze, nontoxic RV antifreeze should be the norm. However, when it comes to our furry friends, they’re precious, so it’s good to be extra careful!

To address pet owners’ understandable concerns, we have a separate, more complete article about pets and antifreeze.

Read Also: Is RV Antifreeze Harmful to Animals?

Is RV Antifreeze Toxic to Plants or Grass?

Some types of antifreeze for RVs are likely to be toxic to plants.

When it comes to RV antifreeze ingredients, only products made using Propylene Glycol will be somewhat less of a concern.

However, it’s best to avoid all contact with plant life to be safe.

Grass fares better when the RV antifreeze is heavily diluted and widely distributed across the lawn or turf. The supply should also be produced using Propylene Glycol.

Read Also: Will RV Antifreeze Kill Grass?

Is It a Good Idea to Add Antifreeze to the Freshwater Tank?

Generally, you should avoid adding RV antifreeze to the freshwater tank.

This is because it can pool at the bottom of the tank and be difficult to remove later.

Certainly, it would be highly advisable to flush the tank repeatedly before considering drinking from the freshwater tank’s supply if you do apply some.

Also, you may wish to use a water testing kit to be sure before consuming water from the freshwater tank after applying RV antifreeze.

Can RV Antifreeze Be Diluted?

Can it be? Yes.

Should you do it? No.

Let us explain…

It’s commonplace to take automotive antifreeze and dilute it down to something less potent. This probably works fine for your car or truck.

However, in the case of an RV or camper, the RV’s plumbing system is being completely flushed out to remove all remnants of water. And then gallons of RV antifreeze replace it.

It’s a completely different process and chemical required for this purpose.

It would be a big mistake to try diluting the RV antifreeze believing it will still protect your plumbing and save you money.

Likely, a cracked pipe will result, and the repair bill will cost substantially more than purchasing a couple more gallons of antifreeze. Therefore, there’s no need for an RV antifreeze dilution chart either.

Please don’t make this mistake!

Can You Winterize an RV without Antifreeze?

It’s possible to expel every droplet of water from the plumbing system of an RV or camper to prepare it for winter storage. Compressed air through an attached air pump is utilized for this purpose and it works great.

Even if you believe that your home state only gets mild winters, you could skip using antifreeze and then the cold period turns ugly!

At that point, the pipes are already frozen up and it’s too late to rush over to apply antifreeze.

For the sake of $25-30, it’s just not worth risking the whole plumbing system on a $5,000 to $10,000 camper or an RV worth tens of thousands of dollars. It’s a false economy and would be an extremely painful mistake.

Treat it as simply part of the cost of ownership every year. Just like with an oil change and other forms of RV maintenance.

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