Winterization with RV antifreeze help

Suza

Member
I will just "ditto" what kernhend says. We used to only "blow" our pipes out in our old camper and one year got particularly cold. Broke our faucets! Now we blow and use antifreeze. Inexpensive insurance! We also plan to use our Unity this winter to go skiing/snowshoeing so we will be doing this more than a few times this winter. We just went through a trial run of adding snow cables to the rear outer tires in our driveway this week and hoodoo ski area opened today! Yay! Let it snow!!
We are going to be in Corvallis next Friday evening for our grand-daughter's concert and will be "camping" in our son's driveway (off Arboretum Rd). How cold has it been getting there? We have already winterized, although it sounds like it is not supposed to get to freezing at our place tomorrow night as forecast. Wondering, do we flush the anti-freeze from our system and hope it doesn't freeze in Corvallis Friday night? I know . . . . how do you accurately predict the weather in Oregon?

You do a fair amount of cold weather camping. How does this work? Do you keep the water lines winterized with anti-freeze and use an alternate source of water? Can you flush a macerator toilet by pouring water into the bowl? I'm not opposed to heating water for washing dishes, we carry drinking water anyway, and I'm ok with foregoing a shower for a few days.

I'm hoping this will get easier once we have a year in our Unity under our belts :rolleyes:
 

Ann Ossinger

2016 Unity MB EuroSport
Just keep an eye on the forecast! This week is supposed to get cold at night (in the 20's) but I think warmer during the day. Yes, my faucets broke in Corvallis! It wasn't so much how cold it got at night, it was how cold it STAYED during the day (mid-20's).

There are two ways to do this, one is what I call "deep cold and fully winterized" and the other is "cold at night, above freezing during the day but not fully winterized" mode. In BOTH cases I like to have electric hook-ups. I boondock spring, summer and fall, but I want electric hookups in the winter. The furnace is too noisy to sleep at night and I don't want to get super cold, so we use a space heater.

Deep cold and fully winterized ("pink stuff" in the macerator, traps, and in the water lines, -empty fresh water tank)

Yes, you carrying your drinking water (we have a 2.5 gallon jug we keep in the shower, plus a gallon container in the fridge) we use for drinking and light cooking. No heavy duty cooking! Just heat and serve stuff. We flush the toilet with our antifreeze. No showers in the RV but we normally park at nice RV parks with electric hook ups and park our RV close to the bathrooms, so we can shower, etc. using our "shower basket" (a little basket with shower shoes, towel, soap/shampoo, etc). We use paper plates, etc. to keep the washing down. I also have an old laundry jug (the kind with a little spigot) filled with water for washing hands and maybe a pot or two. It has another 2.5 gallons or so of washing water that we also keep stored in the shower, but it can rest on the counter with the spigot over the sink. So I don't use ANY water from the now empty fresh water tank if it is going to get and keep cold (below freezing) and I have fully winterized. Lastly I keep another jug or two of anti-freeze and I toss a cup of anti-freeze down the drain for every 2-3 cups of water that goes down the drain. Most RV non-toxic antifreeze is good to -50 degrees, so it will keep things from freezing in 20 degree weather even if it is a bit diluted. I keep non-slip shelf liner in the bottom of my shower to keep the jugs from slipping and sliding.

Cold at night, above freezing during the day, not fully winterized.

We have water in the fresh water tank, we have pink stuff in the macerator, and we blow the lines out after dinner every day. You can still use all the water functions during the day (although we may still use the RV park showers) and we still make sure that we back-fill the macerator with pink stuff after we dump our waste tanks. We are still stingy with the water use so it won't cause any problems.

We also have "heating pads" on our tanks (it was a special order add to our Unity). We can also keep water in the fresh water tank from freezing if night-time temps dip down in the 20's IF WE ARE HOOKED UP TO SHORE POWER. It doesn't work otherwise. We only use this if the daytime temps will go up above freezing during the day. So what we do is we can use the water during the day and up until dinner, then (most days) dump the black and gray tanks, make sure the macerator has "pink stuff" and then we blow out the lines and keep the heating pad "on" for the fresh water. The inside of the rig is kept warm with both the furnace and a small, silent, oil filled space heater. We also remove the shower head of the outside shower and stow in our house. We keep the cabinets open or pour a little pink stuff in the traps. For night-time flushes we use more anti-freeze.

I also use lots of reflectix on the windows, and a big, thin blanket to form a "shield" between the front cab and the house, as the cab is significantly colder (and less insulated) than the house. It really helps! Yeah, we are trying to use a 3 season rig to work 4 seasons. Wish the Unity was a true 4 season rig.

Hope that helps. If anyone else has ideas, chime in!
 
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Suza

Member
Just keep an eye on the forecast! This week is supposed to get cold at night (in the 20's) but I think warmer during the day. Yes, my faucets broke in Corvallis! It wasn't so much how cold it got at night, it was how cold it STAYED during the day (mid-20's).

There are two ways to do this, one is what I call "deep cold and fully winterized" and the other is "cold at night, above freezing during the day but not fully winterized" mode. In BOTH cases I like to have electric hook-ups. I boondock spring, summer and fall, but I want electric hookups in the winter. The furnace is too noisy to sleep at night and I don't want to get super cold, so we use a space heater.

Deep cold and fully winterized ("pink stuff" in the macerator, traps, and in the water lines, -empty fresh water tank)

Yes, you carrying your drinking water (we have a 2.5 gallon jug we keep in the shower, plus a gallon container in the fridge) we use for drinking and light cooking. No heavy duty cooking! Just heat and serve stuff. We flush the toilet with our antifreeze. No showers in the RV but we normally park at nice RV parks with electric hook ups and park our RV close to the bathrooms, so we can shower, etc. using our "shower basket" (a little basket with shower shoes, towel, soap/shampoo, etc). We use paper plates, etc. to keep the washing down. I also have an old laundry jug (the kind with a little spigot) filled with water for washing hands and maybe a pot or two. It has another 2.5 gallons or so of washing water that we also keep stored in the shower, but it can rest on the counter with the spigot over the sink. So I don't use ANY water from the now empty fresh water tank if it is going to get and keep cold (below freezing) and I have fully winterized. Lastly I keep another jug or two of anti-freeze and I toss a cup of anti-freeze down the drain for every 2-3 cups of water that goes down the drain. Most RV non-toxic antifreeze is good to -50 degrees, so it will keep things from freezing in 20 degree weather even if it is a bit diluted. I keep non-slip shelf liner in the bottom of my shower to keep the jugs from slipping and sliding.

Cold at night, above freezing during the day, not fully winterized.

We have water in the fresh water tank, we have pink stuff in the macerator, and we blow the lines out after dinner every day. You can still use all the water functions during the day (although we may still use the RV park showers) and we still make sure that we back-fill the macerator with pink stuff after we dump our waste tanks. We are still stingy with the water use so it won't cause any problems.

We also have "heating pads" on our tanks (it was a special order add to our Unity). We can also keep water in the fresh water tank from freezing if night-time temps dip down in the 20's IF WE ARE HOOKED UP TO SHORE POWER. It doesn't work otherwise. We only use this if the daytime temps will go up above freezing during the day. So what we do is we can use the water during the day and up until dinner, then (most days) dump the black and gray tanks, make sure the macerator has "pink stuff" and then we blow out the lines and keep the heating pad "on" for the fresh water. The inside of the rig is kept warm with both the furnace and a small, silent, oil filled space heater. We also remove the shower head of the outside shower and stow in our house. We keep the cabinets open or pour a little pink stuff in the traps. For night-time flushes we use more anti-freeze.

I also use lots of reflectix on the windows, and a big, thin blanket to form a "shield" between the front cab and the house, as the cab is significantly colder (and less insulated) than the house. It really helps! Yeah, we are trying to use a 3 season rig to work 4 seasons. Wish the Unity was a true 4 season rig.

Hope that helps. If anyone else has ideas, chime in!
Thank you, Ann. Since we are only staying for one night, here is what I am thinking:

Our Unity is already winterized. We won't be needing water during the day and will basically be sleeping and making the usual night time trips to the bathroom. Will keep the fresh water empty and carry drinking/washing water. Will also have a heater going to keep the interior warm. Will put the reflectix shield in the windshield and, depending on how cold it gets, isolate the cab from the coach with a blanket.

My only questions are regarding nighttime flushing:

1. Could we dilute the anti-freeze for flushing 2-3 pts H2O to 1 pt anti-freeze? I need to find out how much water the macerator toilet takes for a "short flush", but I think it is a bit more than a gravity flush.

2. Will flushing the toilet affect any of the other winterization? Just wondering, but I don't think it will.

This will be an experiment. Better to be safe than sorry; since we are only going to be sleeping in the Unity and for one night, will probably not dewinterize, unless, of course, the weather forecast is favorable. Maybe we will get lucky and the temps will stay above freezing through the night. If freezing/snow levels drop below 2,000 feet, we might end up driving our X5 and staying in a motel as we have to go over the pass on Hwy 42 which is 1,800 feet. All the spare beds at our son's are full of guests :smilewink:
 

avanti

2014 GWV Legend 3500 I4
It doesn't really matter how cold it gets--just how long it stays below freezing. Water expands significantly when it freezes, but ICE contracts like any other solid. So, if it is below freezing long enough for the water in your fixtures to freeze (which is often a long time, due to residual heat), the damage is already done. It is a myth that frigid temperatures are more dangerous.
I've been thinking some more about this. Although the physics I cite above is absolutely correct, my conclusion may be overstated. The reason has to do with the use of plastics in RV plumbing. Although PEX is quite resilient to freezing, many other plastics tend to get brittle at low temperatures. So, depending on the materials used in your fixtures, there may indeed be an increased risk of damage in extremely cold temperatures, even though the ice does not continue to expand. Fixtures made of PEX are starting to become available. They are likely to be much more robust than other plastic plumbing products and would probably be worth seeking out in RV applications.

Also, note that the situation is different in heated structures such as your house. In this situation there is a fight between your furnace and Jack Frost to keep the periphery of your house warm. So, in this situation colder is definitely more dangerous
 

Ann Ossinger

2016 Unity MB EuroSport
Suza, I don't know anything about macerator toilets as we have a Murphy Bed model. But as far as keeping water from freezing, a cup of antifreeze to 3 cups of water should keep things from freezing if we are just talking about temps in the 20's. The straight RV antifreeze is for -50 degrees, and that is pretty dang cold!
 

Suza

Member
Suza, I don't know anything about macerator toilets as we have a Murphy Bed model. But as far as keeping water from freezing, a cup of antifreeze to 3 cups of water should keep things from freezing if we are just talking about temps in the 20's. The straight RV antifreeze is for -50 degrees, and that is pretty dang cold!
Another poster, somewhere, mentioned that it doesn't matter how cold it gets - freezing is freezing. And, do anti-freeze and water actually mix?

Hmmmmmm . . . . I sometimes don't know what to think. I guess, erring on the side of caution is best.
 

kernhend

2017 Unity MB
I've been thinking some more about this. Although the physics I cite above is absolutely correct, my conclusion may be overstated. The reason has to do with the use of plastics in RV plumbing. Although PEX is quite resilient to freezing, many other plastics tend to get brittle at low temperatures. So, depending on the materials used in your fixtures, there may indeed be an increased risk of damage in extremely cold temperatures, even though the ice does not continue to expand. Fixtures made of PEX are starting to become available. They are likely to be much more robust than other plastic plumbing products and would probably be worth seeking out in RV applications.

Also, note that the situation is different in heated structures such as your house. In this situation there is a fight between your furnace and Jack Frost to keep the periphery of your house warm. So, in this situation colder is definitely more dangerous
Colder is also more dangerous in an RV not because your physics with respect to the ice are incorrect. Indeed, your statement is correct as is your statement regarding different plastics. What you have left out is this: The rate of cooling of anything depends upon the difference in temperature between the item being cooled and cooling media. In the case of an RV this is the temperature of the water in the plumbing and the temperature of the air. In engineering we call this the "driving force". Simply put, the greater the driving force the faster something cools. The driving force between air at 28F and water at 32F is 4F. Drop the air temperature to 20F and the driving force is tripled -the rate of cooling increases by a factor of 3.

You are also correct to point out that the greatest danger occurs at the phase change of water into ice. Water has a very high heat capacity compared to most other materials so more heat must be removed to cool it. Eighty times as much heat must be removed to change any mass of water at 32F to the same mass of ice at 32F versus changing the same amount of water from 33F to 32F. With a very small driving force there is likely not enough time between above freezing temps in the evening to above freezing temps during the day (the difference between the two being the time below freezing) to cause any damage to the plumbing of a RV so long as the temperature remains in the high 20's. However, increase the driving force by a factor of three and you could be in real trouble.

Consider also that the loss of any component in an RV plumbing system due to freezing will likely disable the entire system. Finding that cracked component might prove to be difficult and entail tearing out some cabinetry to get to it. It will be very expensive. There are those who are fans of using air to blow out a system and winterize it. I get the reasons for this. Using air to blow out a system is fine in theory because obviously if you've removed all the water there is nothing there left to freeze The problem I have is that you can never be sure that you removed all the water and all it takes is a tiny amount in the wrong place and your plumbing system is no longer functional. RV antifreeze plug flows (little mixing) through the plumbing pushing water ahead of it until it finally emerges out of a faucet. You can have a very high level of confidence that the line to that faucet is filled with antifreeze all the way back to the container it is being pumped from.

Finally, I note in the LTV video that Brad recommends using RV antifreeze whenever the temperatures are expected to be below 28F. I take this to be the official position of LTV. The warranty states the following: The foregoing Warranty excludes and does not cover or provide any remedy for damage, defects or loss resulting from abuse or misuse of the motorhome or its equipment, appliances, components, sub-assemblies and/or chassis [from] failure to properly winterize the motorhome.... You could take this to read that if you can establish that you properly winterized your motorhome that some warranty remedy might be possible but that if you did not properly winterize it then no remedy is possible. LTV does not consider that using air to blow out a system is proper winterization under most circumstances according to the company supplied video.
 

kernhend

2017 Unity MB
Another poster, somewhere, mentioned that it doesn't matter how cold it gets - freezing is freezing. And, do anti-freeze and water actually mix?

Hmmmmmm . . . . I sometimes don't know what to think. I guess, erring on the side of caution is best.
RV antifreeze consists of about 45% propylene glycol and 55% water with some red dye thrown in to make it pink. It does not mix with the water in the system because pumping it through the system results in plug flowing the antifreeze through the plumbing and pushing the water out. Any mixing would occur only a inch or so on either side do the water/antifreeze interface. If you poured water and antifreeze together in a bowl they would easily mix. The freezing point of RV antifreeze depends entirely on the glycol content. This is why you must use a lot of antifreeze it you are going to use it to flush your toilet. Pouring a couple of cups of antifreeze into a couple of gallons of gray or black water won't do crap if you'll pardon the pun.
 

Ann Ossinger

2016 Unity MB EuroSport
Another poster, somewhere, mentioned that it doesn't matter how cold it gets - freezing is freezing. And, do anti-freeze and water actually mix?

Hmmmmmm . . . . I sometimes don't know what to think. I guess, erring on the side of caution is best.

Not sure what you mean by this?? There are MANY different degrees of "freezing"!

Pure water below 32 degrees F (and if it isn't under any pressure) will form a crystalline solid that EXPANDS from its liquid state. This makes water unique because most other materials/elements that convert from gasses to liquids, and liquids to solids generally get smaller when they get colder and phase change. Water is an exception (and a good thing too, otherwise our planet would be inhabitable, but I digress.....)

If water can stay in liquid form, it won't cause problems in our RV's. Granted other liquids start having problems when it gets BITTERLY cold, but I'm talking about 20-30 degrees F here in Oregon, in the winter, for our RV's.

Bitterly cold (zero to -10 degrees F or colder) will cause a myriad of other problems for diesel fuel, engine oil, DEF, propane, etc... And I'm sure some of the plastics will start to get more brittle and other problems. I'm not talking about that. I'm just going to talk about WATER.

If you add alcohol to any water it will drop the point of crystallization (freezing) of WATER. RV antifreeze (alcohol) will stay in "semi-liquid" form down to -50 degrees F. Now it is a little slushy at that point, but it is still a "liquid" as it isn't a SOLID. I would have to experiment to get the exact ratios for how much RV antifreeze alcohol to water you need to have for different low temperatures, but AGAIN, I'm talking about 20-30 degrees F. If you were to throw a cup of antifreeze in a quart/liter of water I would bet it makes it safe from freezing (solidification) down to at least 15 degrees F. I'm guessing it is pretty much a linear manner, so for example, a 50/50 water/antifreeze mix should be good to about -10 degrees F, .....see where I'm heading here? And yes, the liquids mix. I'm guessing someone here might be better at the chemistry than I am, but I'm doing this off the top of my head.
 
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kernhend

2017 Unity MB
I would have to experiment to get the exact ratios for how much RV antifreeze alcohol to water you need to have for different low temperatures, but AGAIN, I'm talking about 20-30 degrees F. If you were to throw a cup of antifreeze in a quart/liter of water I would bet it makes it safe from freezing (solidification) down to at least 15 degrees F. I'm guessing it is pretty much a linear manner, so for example, a 50/50 water/antifreeze mix should be good to about -10 degrees F, .....see where I'm heading here? And yes, the liquids mix. I'm guessing someone here might be better at the chemistry than I am, but I'm doing this off the top of my head.
You did it off the top of your head quite well except that the relationship is not linear. Here is the freezing point chart for propylene glycol water mixtures. If you figure that store bought RV antifreeze is about 50/50 PG/H2O then making a 50/50 mix of this will produce a 25% PG/H2O blend. Looking at the chart this would freeze at about 12F. A cup in a quart of water would produce an approximate 12.% PG/H2O blend with a freezing point of about 24F. You can start to see the folly of blending down RV antifreeze.
 
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Aqua Puttana

Poly - Thread Finder
You did it off the top of your head quite well except that the relationship is not linear. Here is the freezing point chart for propylene glycol water mixtures. If you figure that store bought RV antifreeze is about 50/50 PG/H2O then making a 50/50 mix of this will produce a 25% PG/H2O blend. Looking at the chart this would freeze at about 12F. A cup in a quart of water would produce an approximate 12.% PG/H2O blend with a freezing point of about 24F. You can start to see the folly of blending down RV antifreeze.
I believe that the point is you don't need to completely stop freezing. Slush will not damage as will ice.

In my opinion the worst case scenario is freezing followed by partial thawing. The cycle is that the water freezes and slightly expands the parts. A partial thaw allows water to fill in the voids around the frozen plug and expand again when re-freezing. As an example, I have observed the "pregnant" expanded copper water tubing low points in seasonal homes. Of course the plastic piping components typically used in RV's can be even less tolerant of freezing water.

vic
 

Ann Ossinger

2016 Unity MB EuroSport
But remember, the original question was for flushing the toilet.

Your waste tanks shouldn't be "full" if you are winter camping (mine is rarely even a 1/4 tank full!) as you should be using water sparingly. You should be dumping and back-filling with 100% antifreeze for your macerator on a frequent basis. This is to keep waste from freezing up in the tanks. Slush is fine, and it shouldn't be freezing and thawing if you are putting in the antifreeze on a regular basis (but it isn't going to be as much of an issue in a waste tank as it would be with pipes). I certainly am not planning on camping in 10-15 degree weather. Too hard to keep the main cabin at comfortable temps (not to mention the issues of condensation) and then you are also getting close to the gel point on some of the fuels/oils and such. Propane has a harder time with pressure at low temps too. My rule of thumb is to not camp if it is going to get colder than about 20 degrees at night. I'm sure it is possible to do otherwise, but I also like to be comfortable.

Thanks for the freeze chart!
 

LUNITY

2016 LunityTB
Re: Heated tanks

I added the heated tank option on my 2016 TB, as did Ann Ossinger, but only my black and gray waste tanks are affected. The freshwater tank is under the passenger side bed and is at the same temperature, approximately as the cabin. It does not have heated pads.

I expect to be in and out of freezing temperatures in Central Oregon this week and have winterized using compressed air on the water supply side with an empty freshwater tank. Antifreeze in the waste tanks should suffice but I'll turn on the heat pads if necessary. There is a warning to not use the tank heaters unless they have liquid in them but it doesn't say how much. I'm just keeping it to a minimum.
 

kmay

2013 Unity MB
partial winterization

We usually have limited periods of sub-freezing temps, 4 - 5 hours overnight in most cases. While the likelihood of freezing is slim, we do have some isolated pipe freezing on occasion so we want peace of mind.

I am confused by the winterization procedure listed in our 2013 MB manual. It appears there are two procedures. Under heading "Water system winterization - Draining" procedures include draining all the tanks and using air pressure to remove water from lines. Under the heading "Winterization with Plumbing Non-toxic Antifreeze" procedure adds RV antifreeze but there is no mention of tank draining.

There could be two or more meanings to this winterization procedure. In one scenario, EEE intends for users to drain and blow lines then add antifreeze. This seems unlikely from the context of posts in the forum suggesting either procedure is acceptable as a stand alone approach. If either procedure is sufficient, then the omission of draining tanks could either be a mistake or not required. I would like to believe the latter.

To confirm my reading of this, does the winterize valve and water heater bypass operation isolate the fresh water tank and water heater so that one only adds antifreeze to water lines? If so, I could leave tanks partially filled.

As I understand this freezing issue, with sufficient expansion volume and/malleability, the tanks should be okay even with some minor freezing. The real problems are water lines with low volume, p-traps and areas around metal fittings, right?

Thanks for sharing your wisdom,
 

Aqua Puttana

Poly - Thread Finder
Re: partial winterization

...

As I understand this freezing issue, with sufficient expansion volume and/malleability, the tanks should be okay even with some minor freezing. The real problems are water lines with low volume, p-traps and areas around metal fittings, right?
...
I agree that the tanks themselves aren't an issue. The attachments and fittings are the real issue including the plastic body slide dump valves.

We have used our travel trailer trailer toilet in winter. I don't use the water system. I have small plastic containers filled with RV antifreeze for "flushing". (I just dump from the jug, but the measured amount seems to work better for others = less purchasing of antifreeze.) Sanitary wipes are used for hand cleaning. We haven't had any freeze problems using that method.

I realize the above basic method won't work for many people.

vic

Added:

Antifreeze 101 Understanding Burst Points and Freeze Points - StarBrite

https://www.jamestowndistributors.com/userportal/document.do?docId=1144
 
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Suza

Member
Thanks guys (including Ann). I'll buy a couple gallons of the stuff in case there's a deep frost warning
We had two gallons for our TB and, by the time we dumped a cup in each drain, it was just enough. This included flushing some into the macerator toilet and for the macerator pump. As this was our first winterization, we might have been a bit slow shutting off faucets once the pink started running out; 2 gallons might have been plenty.

We did use the antifreeze that filled the filter canister to dump in the toilet for the macerator.

I would get three gallons just to be safe. Then you will have a spare :rolleyes:

Anyone know where you can get the antifreeze in two gallon jugs? This would be handier than packing along two gallons, and you wouldn't need to move the pickup hose to the second gallon in the middle of the process.
 

Suza

Member
I don't know if anyone has suggested this as a winterization solution, so I am going to throw it out there. It is the simplest, though by no means the most economic, way to protect your RV:

Build a heated RV garage for storing your Unity. This will not help those who wish to venture out during the cold season, but solves many storage concerns:

Freezing
UV damage
Exposure to other environmental elements
Bird dropping deposits
Condensation

And, if you can successfully rodent proof the garage (not sure of the chances of this), the problem of damage from invasive critters.

One downside to this method:

People driving by won't know what an awesome motorhome you have :laughing:
 

alichty

2014 LTV Unity TB
My solution to winterizing my TB for this week's hard freeze was to scamper over to the OR coast instead..

33F in Newport last night and 33 forecast for Florence tonight. Jumps up into the 40's tomorrow all along the southern OR coastline. Downright toasty :cheers:

Things might get a little damp however.....
 

Suza

Member
My solution to winterizing my TB for this week's hard freeze was to scamper over to the OR coast instead..

33F in Newport last night and 33 forecast for Florence tonight. Jumps up into the 40's tomorrow all along the southern OR coastline. Downright toasty :cheers:

Things might get a little damp however.....
Still 36 degrees in Bridge (about 30 mi east of the coast) but expected to get below 30 by morning.

Have heaters on in our winterized Unity and the potting shed, where my sensitive plants are wintered.

Shouldn't rain tonight. If we get precipitation, it will be in the form of snow :smilewink:
 

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