Draining antifreeze from potable water tanks

[Hawkmouth]

Hi all. I have a question about draining my antifreeze to get my water system running. Everything I’ve read says drain the antifreeze out and proceeded with sterilization. My question is how fo you dispose of the antifreeze? Should I run the sinks into a bucket and take to the hazardous waste? It seems like a lot of bucket hauling for flushing the water tanks. I’d there a better way?

Thanks.

[marcjsmith]

presumably you' d be using pink non toxic antifreeze, which is safe to dispose via normal sewage channels.

[Rohan]

Originally Posted by Hawkmouth

Hi all. I have a question about draining my antifreeze to get my water system running. Everything I’ve read says drain the antifreeze out and proceeded with sterilization. My question is how fo you dispose of the antifreeze? Should I run the sinks into a bucket and take to the hazardous waste? It seems like a lot of bucket hauling for flushing the water tanks. I’d there a better way?

Thanks.

If you used anti-freeze for cars then yes dispose of it somewhere and totally flush your water tanks out several times before ever drinking from that water.



However, that would be very unusual. I'm 99% certain what you have is marine anti-freeze, which is non toxic and can be dumped in the water. You can even drink it (supposedly it won't kill you, although it could make you a little sick). Just flush out your system with a little fresh water and you will be fine.

[Hawkmouth]

Originally Posted by Rohan

If you used anti-freeze for cars then yes dispose of it somewhere and totally flush your water tanks out several times before ever drinking from that water.



However, that would be very unusual. I'm 99% certain what you have is marine anti-freeze, which is non toxic and can be dumped in the water. You can even drink it (supposedly it won't kill you, although it could make you a little sick). Just flush out your system with a little fresh water and you will be fine.

Yes, it’s the pink antifreeze. I’m pretty sure it’s the marine kind. I would like the ease of just flushing it out of the boat into the water but I read that even the non toxic antifreeze is an environmental hazard. Does anyone have anything to add to this?

[PirateFoxy]

If you’re really concerned you can dump the non-toxic stuff at any RV dump station or similar - that’s how most RVrs de-winterize.

[Boatyarddog]

Originally Posted by Hawkmouth

Hi all. I have a question about draining my antifreeze to get my water system running. Everything I’ve read says drain the antifreeze out and proceeded with sterilization. My question is how fo you dispose of the antifreeze? Should I run the sinks into a bucket and take to the hazardous waste? It seems like a lot of bucket hauling for flushing the water tanks. I’d there a better way?

Thanks.

Nothing toxic, should be dumped in the water, ever.
That being said pink (propylene glycol) is mildly toxic to fish, animals and other things.
It should be recovered, recycled, reused.

Explained pretty well here,https://forestandshanna.com/this-is-...rv-antifreeze/
The amount of RV antifreeze used in winterizing your potable water system should be small 2 or 3 gallons since one should empty tanks and what's left in your lines.
Do not use in your hot water tank as it can cause biological growth, drain the tank and winterize lines only, you may need to install a bypass valve for this, commonly done on RVs.
Regular antifreeze can be used to winterize black water systems, because its collected at pump outs.
Possibly, collect the used winterizing Antifreeze from your water system and drain into your Black water tank and then use a pump out to empty it.
That's my solution.
SV Cloud Duster

[Hawkmouth]

Thank you! That article is very helpful boaytyarddog.

[PirateFoxy]

Originally Posted by Boatyarddog

Nothing toxic, should be dumped in the water, ever.
That being said pink (propylene glycol) is mildly toxic to fish, animals and other things.
It should be recovered, recycled, reused.

You can reuse it? So in theory we could just save it year to year if we had space?

[Boatyarddog]

Originally Posted by Hawkmouth

Thank you! That article is very helpful boaytyarddog.

Your most welcome!
I like the idea of recovery, and reuse.
Actually doing that is inconvient for most, but the collection to the Waste tank and a pump out seems most practical.
Thank for asking the questions.
Sail on
Boatyarddog

[Boatyarddog]

Originally Posted by PirateFoxy

You can reuse it? So in theory we could just save it year to year if we had space?

Sure, you can.
As mentioned you don't need much to winterize, you really just need to see the color in the system.
Also, glycol has alcohol in it, not great for seals, but not a problem unless left for years in the system.
Pink antifreeze will slush up when cold temp. hits but will not freeze solid and thus damage stuff.
SV Cloud Duster

[garyfdl]

Originally Posted by Hawkmouth

Yes, it’s the pink antifreeze. I’m pretty sure it’s the marine kind. I would like the ease of just flushing it out of the boat into the water but I read that even the non toxic antifreeze is an environmental hazard. Does anyone have anything to add to this?

How much are we talking about? Propylene glycol is non toxic and bio degradable. If it's just what's in the lines to the galley and head I wouldn't be too concerned. If it's more than a gallon, you might want to dilute it with clear water as it goes down the drain. You could also just dump it in the head.

Most regulatory agencies don't want anything 'foreign' introduced into the waterways. At our yacht club (in Wisconsin) we aren't even allowed to put ice that came off the lake during a shove, back in the lake - but it's OK to pile it on shore and let it melt and return 'naturally'.

[Boatyarddog]

Originally Posted by garyfdl

How much are we talking about? Propylene glycol is non toxic and bio degradable. If it's just what's in the lines to the galley and head I wouldn't be too concerned. If it's more than a gallon, you might want to dilute it with clear water as it goes down the drain. You could also just dump it in the head.

Most regulatory agencies don't want anything 'foreign' introduced into the waterways. At our yacht club (in Wisconsin) we aren't even allowed to put ice that came off the lake during a shove, back in the lake - but it's OK to pile it on shore and let it melt and return 'naturally'.

That being said pink (propylene glycol) is mildly toxic to fish, animals and other things.
It should be recovered, recycled, reused.

Explained pretty well here,https://forestandshanna.com/this-is-...rv-antifreeze/

SV Cloud Duster

[deblen]

If you are going to re-use propylene glycol for anti-freeze,you should recheck it's freezing point. PG is used for many other things & is FDA safe. Cheers/Len


https://www.verywellhealth.com/propylene-glycol-5076050

[garyfdl]

Originally Posted by Boatyarddog

Also, glycol has alcohol in it, not great for seals, but not a problem unless left for years in the system.
Pink antifreeze will slush up when cold temp. hits but will not freeze solid and thus damage stuff.

My understanding is propylene glycol is a lubricant, will not damage seals and as advertised as being safe/suitable for rubber and other seal compounds.

As for "slush up" although I've never checked, the stuff I use is rated to -50F, (my car is only rated to -35F).

[garyfdl]

Originally Posted by Boatyarddog

That being said pink (propylene glycol) is mildly toxic to fish, animals and other things.
It should be recovered, recycled, reused.

Can you express "mildly toxic" in quantifiable terms?

There is nothing wrong with recover, reuse, recycle, if it makes practical sense to do so.

At the start of the season, the quart or so I recover goes down the head. but most of what's in the engine gets blown out the exhaust; I've never seen a trail of dead fish or other aquatic life in my wake.