Propylene Glycol RV antifreeze

E

emerystora

New member
Apr 6, 1999
14,608
1
1
Most places are now selling RV antifreeze with ethyl alcohol. I much prefer the propylene glycol product.
It is getting harder to find but I just some some today at Lowes on sale for $3.98 per gallon.

Emery Stora
 
Ethyl alcohol? If so can we just pour Everclear in there?
--
John Lebetski
Chicago, IL
77 Eleganza II
Source America First
 
Everclear? Sounds like what we use to make PJ out of years ago.
--
Joe Kemenczky
1975 Eleganza ll "Odie" 75,000 miles.
Working on complete restoration. In year 2 of a 3 year restoration.
Loving every minute!
Monroe, NC (East of Charlotte).
 
John
You may have missed something I posted about 4 weeks ago.

NOW LET ME TELL YOU A FEW THINGS ABOUT THE PINK RV ANTIFREEZE.

When you buy it check the label. A lot of it is not propylene gylcol. I bought some this year and when I got it home I saw on the label that it said it contained ethyl alcohol. That is being commonly used in RV antifreeze now because its a LOT cheaper than propylene glycol. BUT it is not as good for giving freeze protection.

When you find a propylene glycol pink bottle it will often say "do not add water - it gives -50 deg F protection right out of the bottle"

I tested that bottle with ethyl alcohol and found that it indeed did have -50 deg F protection -- why? because my testing showed that it already had been diluted with 42% water in the bottle. Think about it - what is cheaper for the bottler -- water or propylene glycol?

So when you buy it at Walmart or other such places for perhaps $2.00 a gallon, don't expect it to be pure propylene glycol. It will definitely have a lot of water in it. The bottler cannot buy propylene glycol for $2.00 anymore and he wants to make a profit. More likely, though, that $2.00 bottle will be ethyl alcohol instead of propylene glycol.

Larry - when you say "run the pink stuff through which usually shows pure antifreeze" you are kidding yourself. It is not pure antifreeze -- it just means that the pure water has been pushed out ahead of the pink stuff. Don't worry, there is enough antifreeze to protect your pipes even with a lot of water in it. In fact, you would not want pure antifreeze in the lines as they would freeze at fairly high temperatures.
It would be hard to purchase any pure propylene glycol antifreeze anywhere as it would have a cost between $10 to $15. per gallon.

I was reading some of the postings on the internet sites as was appalled by just how much misinformation and untruths are being posted. On one site someone said that adding water would not bring down the freeze point and that adding water was only to increase the boiling point. Exactly the opposite of what happens when adding water. For antifreeze the more glycol, the higher the boiling point. However if you have too much glycol you will have a high freezing point and less heat transfer. That is why a 50% mixture (ethylene glycol) is recommended for automobiles - that gives good boiling point protection and a -34 deg freeze point.

That is as bad as the earlier posting about the shop foreman that said not to put pink antifreeze into a water pump because it would cause the pump to break. That is a whole lot of BS or a foreman that is so badly informed that he is believing "old wife's tales". The picture of the pump with the crack was probably caused by pure water which will expand when freezing. Even pure propylene glycol would not crack the pump because it does not expand like water does when it freezes.

For RV water systems you don't worry about the boiling protection -- only the freezing point. So, if you want protection down to say -20 deg F then you could tolerate up to 55% water and 45% propylene glycol. But if you should buy a bottle of the pink stuff that says it gives protection to -50 out of the bottle they be aware that you already have 42% water in that bottle so don't add a lot more.

If you happen to buy a bottle of the pink stuff that says it has ethyl alcohol in it and the label says it has a -50 freeze point that means that it already has about 42% water added to it. If you add more water to give, for example a 40% level of ethyl alcohol it would have a freeze point of -22 deg F.

>
>
> Ethyl alcohol? If so can we just pour Everclear in there?
> --
> John Lebetski
> Chicago, IL
> 77 Eleganza II
> Source America First
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
 
Emery,

My recently acquired pink Arctic-Ban anti-freeze says "Safe - Odorless - Non-Staining".
It lists ingredients as:
Ethyl Alcohol
Glycol
Denaturants
Colorant
Water
In that order, but this is not FDA so that may not be the order of contribution.

Questions for Emery:
1 - Is there an approved "Denaturant" for Ethyl Alcohol that is safe for human consumption? (that you know of)
2 - Does the unspecified glycol in something sold for potable systems mean it has to be propylene glycol?
3 - The instructions say that when de-winterizing run water until all color is gone, but will this reduce the possible toxic contents to an absolutely safe level?

Fortunately, I blow the system dry and only use the antifreeze in the drains. (No, I'm not sure why I bought 3 gallons When I use about a 1/3 a year.)

If it used it in the potable system, I would be off hunting the propylene glycol or like a friend that has honestly taken up using cheap vodka - neat.

Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air)
Now with 4 working Rear Brakes
SE Michigan - Twixt A2 and Detroit
 
> 1 - Is there an approved "Denaturant" for Ethyl Alcohol that is safe for human consumption? (that you know of)

It is my understanding that Denatonium is a standard denaturant not only for antifreezes, ethanol and methanol but also for soaps, shampoos and other substances that humans may have incidental contact with. The wikipedia article says:

"It is not known to pose any long term health risks"

Apparently it is now being added to "canned air" to discourage huffing.

My approach is to follow the instructions in the GMC manual that describe a winterizing process that does not involve putting RV antifreeze in the system.

--Jim Miller
1977 Eleganza II
1977 Royale
Hamilton, OH
 
My approach is to follow the instructions in the GMC manual that describe a winterizing process that does not involve putting RV antifreeze in the system.

--Jim Miller
1977 Eleganza II
1977 Royale
Hamilton, OH

_______________________________________________


The manuals must be different from year to year. My ?Motorhome 1976 Operating Manual Model ZEO6581? states that for ?Winter Storage-Below 32F. (0C)" to use antifreeze.

Page 102, section 3, paragraph i: ?......Add antifreeze solution (5 gallons non-toxic, non-flammable antifreeze and 5 gallons water) to living area water tank. Open all faucets and turn on water pump. When colored water comes out of the faucets, close faucets?....?

For the past 15 years my procedure is to drain the freshwater tank, blow out the lines via the city water inlet with compressed air (at around 30PSI) including both water heaters (OEM electric and my new LP tankless heater). Then isolate both heaters with water heater bypass valves. Then I use a winterizing kit to pump the pink stuff through the system. Pour pink stuff into the traps and a gallon in the previously drained and cleaned black water tank. I run the macerator for a few seconds until I see pink in the discharge hose.

I never add antifreeze to the fresh water tank because it is a real bear to get rid of it in the spring. I rely on just draining it to winterize. I've also found that it is a hassle if you get antifreeze in the electric water heater. It seems to take a lot of flushing to get it out.

This all takes less than 30 minutes and 2.5 gallons of the -50 degree antifreeze (I don?t add water). I used to use about a gallon of antifreeze when I didn?t have the tankless water heater, water filter and macerator. So far, no problems in the 16 times I?ve done it that way.
--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com
 
>
>

>
> Emery,
>
> My recently acquired pink Arctic-Ban anti-freeze says "Safe - Odorless - Non-Staining".
> It lists ingredients as:
> Ethyl Alcohol
> Glycol
> Denaturants
> Colorant
> Water
> In that order, but this is not FDA so that may not be the order of contribution.
>
> Questions for Emery:
> 1 - Is there an approved "Denaturant" for Ethyl Alcohol that is safe for human consumption? (that you know of)
> 2 - Does the unspecified glycol in something sold for potable systems mean it has to be propylene glycol?
> 3 - The instructions say that when de-winterizing run water until all color is gone, but will this reduce the possible toxic contents to an absolutely safe level?
>

The denaturing of ethyl alcohol is solely done to prevent it from being consumed by humans. If not done then people would use it in place of expensive "booze".

The most common denaturants are pyridine which gives the mixture a very unpleasant odor. It can be toxic but in the very low levels it is not a problem.

Another one is denatonium which is added to give it an extremely bitter flavor. It is the most bitter chemical compound known. It was discovered in 1958 during research on local anesthetics. Dilutions of as little as 10 ppm are unbearably bitter to most humans.

Emetic agents (vomiting) such as syrup of ipecac is also sometimes used.

All of these are low toxicity and used in such small amounts that they are easily flushed from the water lines and not a problem.

As previously discussed there are two types of RV Antifreeze.
1. Propylene glycol based which is non-toxic and gives the best freeze protecion and doesn't attack gaskets and seals.
2. Ethyl alcolol based which is less expensive and has denaturants added which have some low toxicity. Ethyl alcolol will attack rubber and plastic seals such as on drain valves and plumbing junctions.

Propylene glycol materials are more expensive but I much prefer them. They are totally non-toxic wheras the ethyl alcohol additives are suspect.

The other glycols used in the ethyl alcohol may or may not be approved for use in potable water systems. However I would assume that it would be in very low levels.
Running the water until the color is gone should reduce the possible toxic chemicals to a level where they wouldn't be dangerous. But I would flush for quite some time after the pink is gone.

Emery Stora
 
I use a similar routine, starting with an empty holding tank.

* Turn on fresh water pump.

* Lay shower hose on bathroom floor.

* Open bathroom hot water; run until air bubbling quits then turn off hot.

* Do same for cold bath faucet.

* Repeat for kitchen faucet.

* Turn off fresh water pump.

* Hook external air compressor to city water inlet with adaptor.

* Repeat previous steps using air to clear lines fully.

* Activate shower diverter and clear shower hose for both hot and cold.

* Turn off each water valve when no water comes through.

* Flush toilet.

* With air still running, disconnect water feed to toilet to drain that line into shower drain.

* Turn off external air compressor.

* Fill P-traps of bathroom, kitchen, and shower drain with pink stuff.

* With holding tank drain open, you know you have enough pink in each drain when a little bit of pink drains out the pipe. Put the cover back on the drain pipe.

I used just about a gallon of pink. At this point, I figure any residual water has plenty of room to expand without damaging anything.

Have a beer or such and wait for Spring.


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~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
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> To: gmclist
> From: mygmc
> Date: Thu, 28 Nov 2013 12:31:22 -0600
> Subject: Re: [GMCnet] Propylene Glycol RV antifreeze
>
> My approach is to follow the instructions in the GMC manual that describe a winterizing process that does not involve putting RV antifreeze in the system.
>
> --Jim Miller
> 1977 Eleganza II
> 1977 Royale
> Hamilton, OH
>
> _______________________________________________
>
>
> The manuals must be different from year to year. My ?Motorhome 1976 Operating Manual Model ZEO6581? states that for ?Winter Storage-Below 32F. (0C)" to use antifreeze.
>
> Page 102, section 3, paragraph i: ?......Add antifreeze solution (5 gallons non-toxic, non-flammable antifreeze and 5 gallons water) to living area water tank. Open all faucets and turn on water pump. When colored water comes out of the faucets, close faucets?....?
>
> For the past 15 years my procedure is to drain the freshwater tank, blow out the lines via the city water inlet with compressed air (at around 30 PSI) including both water heaters (OEM electric and my new LP tankless heater). Then isolate both heaters with water heater bypass valves. Then I use a winterizing kit to pump the pink stuff through the system. Pour pink stuff into the traps and a gallon in the previously drained and cleaned black water tank. I run the macerator for a few seconds until I see pink in the discharge hose.
>
> I never add antifreeze to the fresh water tank because it is a real bear to get rid of it in the spring. I rely on just draining it to winterize. I've also found that it is a hassle if you get antifreeze in the electric water heater. It seems to take a lot of flushing to get it out.
>
> This all takes less than 30 minutes and 2.5 gallons of the -50 degree antifreeze (I don't add water). I used to use about a gallon of antifreeze when I didn't have the tankless water heater, water filter and macerator. So far, no problems in the 16 times I've done it that way.
> --
> Richard
> 76 Palm Beach
> SE Michigan
> www.PalmBeachGMC.com

 
>
> As previously discussed there are two types of RV Antifreeze.
> 1. Propylene glycol based which is non-toxic and gives the best freeze protecion and doesn't attack gaskets and seals.
> 2. Ethyl alcolol based which is less expensive and has denaturants added which have some low toxicity. Ethyl alcolol will attack rubber and plastic seals such as on drain valves and plumbing junctions.
>
> Propylene glycol materials are more expensive but I much prefer them. They are totally non-toxic wheras the ethyl alcohol additives are suspect.
>
> The other glycols used in the ethyl alcohol may or may not be approved for use in potable water systems. However I would assume that it would be in very low levels.
> Running the water until the color is gone should reduce the possible toxic chemicals to a level where they wouldn't be dangerous. But I would flush for quite some time after the pink is gone.
>
> Emery Stora
> _______________________________________________



I never paid attention before to the ingrediants in the pink stuff before. The antifreeze I used this time (ethyl alcohol, propylene glycol, water etc.) has on the label "is compatible with all metal and and plastic components (except acetate)." I wonder if I should I worry about the "rubber" gasket/seal in my toilet and my macerator's impeller?

If the formulations for the antifreeze has changed over the past 15 years, going from good to not so good for the plumbing, I might want to rethink trying to buy the cheapest product i can find.
--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com
 
>> I wonder if I should I worry about the "rubber" gasket/seal in my toilet and my macerator's impeller?
>
Yes, I would. The ethanol could cause it to swell.

> If the formulations for the antifreeze has changed over the past 15 years, going from good to not so good for the plumbing,

The reason that many have gone to the ethanol product is strictly price. People like to buy the $2.00 per gallon stuff but they don't read or don't understand the label. You used to find sales on the propylene glycol at $2.00 but no longer.
 
I hit send before I was done.

Yesterday I posted that Lowes had the propylene product on sale for $3.98. That is the cheapest I have seen it in a very long time. I plan to buy a few gallons.

Emery Stora

>
>

>
>>> I wonder if I should I worry about the "rubber" gasket/seal in my toilet and my macerator's impeller?
> Yes, I would. The ethanol could cause it to swell.
>
>> If the formulations for the antifreeze has changed over the past 15 years, going from good to not so good for the plumbing,
>
> The reason that many have gone to the ethanol product is strictly price. People like to buy the $2.00 per gallon stuff but they don't read or don't understand the label. You used to find sales on the propylene glycol at $2.00 but no longer.
 
Emery,

The cigar aficionados here will know the following; if you mix propylene glycol in a 50 / 50 mix with distilled water you get a
liquid that will maintain your humidor at 70 percent RH @ 70 degrees F which are the ideal storage conditions for cigars!

Also IIRC propylene glycol is used to dilute medicines administered in a liquid form.

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
 
-----Original Message-----
From: Emery Stora

The denaturing of ethyl alcohol is solely done to prevent it from being consumed by humans. If not done then people would use it in
place of expensive "booze".

The most common denaturants are pyridine which gives the mixture a very unpleasant odor. It can be toxic but in the very low levels
it is not a problem.

Another one is denatonium which is added to give it an extremely bitter flavor. It is the most bitter chemical compound known. It
was discovered in 1958 during research on local anesthetics. Dilutions of as little as 10 ppm are unbearably bitter to most humans.

Emetic agents (vomiting) such as syrup of ipecac is also sometimes used.

All of these are low toxicity and used in such small amounts that they are easily flushed from the water lines and not a problem.

As previously discussed there are two types of RV Antifreeze.
1. Propylene glycol based which is non-toxic and gives the best freeze protecion and doesn't attack gaskets and seals.
2. Ethyl alcolol based which is less expensive and has denaturants added which have some low toxicity. Ethyl alcolol will attack
rubber and plastic seals such as on drain valves and plumbing junctions.

Propylene glycol materials are more expensive but I much prefer them. They are totally non-toxic wheras the ethyl alcohol additives
are suspect.

The other glycols used in the ethyl alcohol may or may not be approved for use in potable water systems. However I would assume
that it would be in very low levels.
Running the water until the color is gone should reduce the possible toxic chemicals to a level where they wouldn't be dangerous.
But I would flush for quite some time after the pink is gone.

Emery Stora
 
Emery Stora answered my questions most effectively on Thu, 28 November 2013 14:46

Emery,

Thank You,
It is very comforting to have a native guide when in strange territory.

Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumière (say show-me-air)
Now with 4 working Rear Brakes
SE Michigan - Twixt A2 and Detroit
 
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