I live in Canada near Ottawa, and I will be leaving our Sunseeker 24 outside this winter. I went to Canadian Tire to buy some antifreeze to put in the waterlines for the toilet, shower etc and the clerk said to use some windshield washer. Is that good or bad advice? Last year, I bought some Hall-Chem "economical plumbing antifreeze" that contains non toxic Ethanol and propylene glycol. The stuff I am thinking of using is labeled "all season windshield washer fluid -35" but says POISON, so am somewhat concerned/doubtful... It doesnt say what's in it. It is blue instead of pink.

If it says poison then don’t use it in any RV system. Only use anti freeze designed for RV water systems. It is a good idea to make sure your windshield washer fluid contains washer fluid safe to -35 though. When you pour it in, run the windshield washer to make sure the fluid gets through the lines.

Bad advise, except maybe for an emergency. WW fluid is methanol. Lets look at it--Emergency and Hazards Overview DANGER: (Skull & Crossbone symbol) POISON. MAY BE FATAL OR CAUSE BLINDNESS IF SWALLOWED. VAPOR HARMFUL. FLAMMABLE.RV antifreeze is PROPYLENE GLYCOL, relativly safe. Plus,the methanol might affect the plumbing.

I think I would be talking to the manager about the idiot clerk trying to kill customers.

Windshield washer fluid is a brightly-colored liquid made of methanol, a poisonous alcohol. Sometimes, small amounts of other toxic alcohols, such as ethylene glycol, are added to the mixture.https://medlineplus.gov/ency/article/002803.htmI agree. Someone needs to educate that person before someone is harmed.

Windshield washer fluid is NOT acceptable to winterize your water lines. Do not use it.The stuff to use is non-toxic RV antifreeze. Use nothing else, except air. Blow out the lines with a low pressure air compressor (20 psi is plenty, but under no circumstances more than about 50 psi) to remove as much water as possible, then fill those lines with the pink RV antifreeze. Though more expensive than windshield washer fluid, it is a LOT cheaper than a liver transplant. Trust me on that one.

Windshield washer OK for winterizing waterlines?

bobndot
Explorer II
Oct 30, 2021
I guess you could always use vodka if you're in a pinch. :) Next season when you open it back up, invite us over.
Grit_dog
Navigator
Oct 29, 2021
LOL, someone working at the Walmart of Canada said to use Wiper Juice in water lines?
It's good you came here to ask then, if there was any real question in your mind.

What may have happened was the "clerk" was referring to drain lines/P traps, not freshwater lines.
I've used Wiper juice interchangeably with RV antifreeze for years for drain lines in the camper, winterizing a home and winterizing fresh water ballast pumps and tanks in my boat. Works fine for that.
MDKMDK
Explorer
Oct 29, 2021
Eskimo007 wrote:
I live in Canada near Ottawa, and I will be leaving our Sunseeker 24 outside this winter. I went to Canadian Tire to buy some antifreeze to put in the waterlines for the toilet, shower etc and the clerk said to use some windshield washer. Is that good or bad advice?

Last year, I bought some Hall-Chem "economical plumbing antifreeze" that contains non toxic Ethanol and propylene glycol.

The stuff I am thinking of using is labeled "all season windshield washer fluid -35" but says POISON, so am somewhat concerned/doubtful... It doesnt say what's in it. It is blue instead of pink.

If it's just going down the toilet or shower drains, it should work to resist freezing in the traps. I think someone said in an emergency?
The concern is what the ingredients in the ww antifreeze might do to the seals and valves it will come into contact with downstream. Pure alcohols will cause harm to rubber, and who knows what else, in the short plumbing run from those appliances (shower/toilet) to the exit drains.
The pink stuff usually has added lubricants, and is less likely to damage plumbing componenets.
If you can, use the pink stuff, before the blue stuff.
bobndot
Explorer II
Oct 29, 2021
Buy the correct rv or boat non toxic antifreeze.
There is alcohol base rv antifreeze as well. That is less expensive but can leave a taste in the lines.

https://recvehicle.com/winterization-and-rv-antifreeze/

Don't forget to pump it thru the outside shower if you have one.

Pour a cup of rv antifreeze down each drain as well . Sinks and shower.
Dusty_R
Explorer
Oct 29, 2021
If you have a shop vacuum that you can put the hose on the output, blower, use that to blow out the fresh water lines.
gbopp
Explorer
Oct 29, 2021
You received poor advice. Do not put poison in your water system.
If you can't find the proper antifreeze, blow out your water lines.
naturist
Nomad
Oct 29, 2021
Windshield washer fluid is NOT acceptable to winterize your water lines. Do not use it.

The stuff to use is non-toxic RV antifreeze. Use nothing else, except air. Blow out the lines with a low pressure air compressor (20 psi is plenty, but under no circumstances more than about 50 psi) to remove as much water as possible, then fill those lines with the pink RV antifreeze. Though more expensive than windshield washer fluid, it is a LOT cheaper than a liver transplant. Trust me on that one.
BB_TX
Nomad
Oct 29, 2021
Windshield washer fluid is a brightly-colored liquid made of methanol, a poisonous alcohol. Sometimes, small amounts of other toxic alcohols, such as ethylene glycol, are added to the mixture.

https://medlineplus.gov/ency/article/002803.htm

I agree. Someone needs to educate that person before someone is harmed.
RedRollingRoadb
Explorer
Oct 28, 2021
I think I would be talking to the manager about the idiot clerk trying to kill customers.
MT_BOB
Explorer
Oct 28, 2021
Bad advise, except maybe for an emergency. WW fluid is methanol. Lets look at it--
Emergency and Hazards Overview
DANGER: (Skull & Crossbone symbol) POISON. MAY BE FATAL OR CAUSE BLINDNESS IF
SWALLOWED. VAPOR HARMFUL. FLAMMABLE.

RV antifreeze is PROPYLENE GLYCOL, relativly safe. Plus,the methanol might affect the plumbing.

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Windshield washer OK for winterizing waterlines?

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