Antifreeze CO2 & Propane Alarm

[HDRider]

I wanted to alert you guys that when you winterize the antifreeze might set of your CO2 alarm.

 

We never had it happen before but we sure did yesterday.  I reset it a bunch of times and kept scratching my head.  Cindy found something via the Google about it. The antifreeze has alcohol in it and can set off the alarm.

 

I just found these other little tidbits about RV Antifreeze -  

• Drying Rubber Seals: Repeated long-term exposure to high-concentration ethanol can dry out or degrade rubber O-rings, pump diaphragms, and toilet blade seals over time.

• Taste & Odor: Ethanol leaves a distinct alcohol smell and can impart a persistent chemical taste to PEX lines and vinyl hoses that takes extensive flushing to remove in the spring.

• Flammability: Because of the grain alcohol content, some low-cost ethanol-blend antifreezes are potentially flammable in concentrated liquid or vapor forms when exposed to an open flame.

 

[HDRider]

I aired out the Ollie overnight and the alarm is off and that pretty little green light is bright and shiny. 

[Geronimo John]

6 hours ago, HDRider said:

Cindy found something via the Google about it. The antifreeze has alcohol in it and can set off the alarm.

Great post and thank you Cindy!  Below is a long version with a couple of alternate RV products than the Super Walment Center Super Tech version that many of us have been using.  

Owners: 

• If there are other less expensive sources please advise all.  
• Have we seen any long term damage in our OTT's?  (I have used it for 9 winters and have not experiencned any).  If none by others then maybe the topic is over-blown.

GJ

 

RV ANTIFREEZE (Keep).docx 

[Steph and Dud B]

According to the product page, Supertech RV Antifreeze contains Glycerin (Glycerol): An additive that helps lubricate and protect plumbing seals. Also Propylene Glycol: A non-toxic (to humans when used as directed) organic compound that lowers the freezing point. So, it's not all ethanol. Never had an issue ourselves in the past 27 years.

On the other hand, we have had a CO/gas detector become overly sensitive and need to be replaced.

 

Edited November 1 by Steph and Dud B
Added info.

[Geronimo John]

On 10/31/2026 at 3:28 PM, Steph and Dud B said:

On the other hand, we have had a CO/gas detector become overly sensitive and need to be replaced.

As have we.  Not sure I could blame their demise on our winterization using Super Tech though.....

[John Dorrer]

Yes, had our alarm go off, and discovered the detector was close to its 5 year life. I replaced it. I now cover my detector with seranwrap while trailer is winterized and stored. No more problems.

 

RV antifreeze is human safe and it is designed to keep "O" rings and other components lubricated.

 

When we de-winterize, we  run fresh water through the lines, we close the fresh tank, and reconfigure the knobs, add a 1/4 cup of bleach into the hose, connect the hose to the fresh tank fill and fill the fresh tank. We run water through the lines, let things sit for an hour, and drain the tank. We refill the tank and are ready to travel.

 

No where have I found anything posted that RV Antifreeze will damage your seals or components.

 

We have hard water in Indiana and use a On The Go Water Softener and top of the line single filter whenever we fill up. Filter by The FitRV

Edited November 3 by John Dorrer
Typo

[John Dorrer]

We buy our RV antifreeze at ACE Hardware. This is the safest product. They don't list the type. The white cap is the correct one, and safe for lines, connections and gaskets. Sorry, I cut of the cap, but it is the white cap.

 

 

Edited November 4 by John Dorrer
Updated Comment

[Dream Girl]

I  have no power it seems after changing out CO Propane Alarm   A one amp fuse is listed for the alarm unit.  It is listed as F57 in owners manual.  Does anyone possibly know where the fuse could be located.   Any help is appreciated before taking it back    Mike

[jd1923]

28 minutes ago, Dream Girl said:

I  have no power it seems after changing out CO Propane Alarm   A one amp fuse is listed for the alarm unit.  It is listed as F57 in owners manual.  Does anyone possibly know where the fuse could be located.   Any help is appreciated before taking it back    Mike

Mike, I'm guessing you mean no power to the CO monitor only and other things like the cabin lighting works. You likely blew the fuse when cutting the wires. I've done that too often where I should just locate and remove the fuse first!

So, our hulls 5 years apart are going to be different. Look at the wiring below the CO monitor inside the front of the rear dinette seat and there should be an inline fuse there. If not, follow the wiring if you can and an inline fuse may be at the other end of the wire at a positive bus.

Yeah, it will be a thin inline fuse holder for the light 1A fuse. Look at the +bus where you'll see 3 big yellow inline fuses for the jacks. See if there may be 1-2 other fuses attached there, but my first look would be below the CO monitor.

[Hokieman]

3 hours ago, Dream Girl said:

Does anyone possibly know where the fuse could be located.

I also have a 2021 model.  My 1A in-line CO fuse is under the street side bunk, attached to the 60A breaker.   See snip from the 2019 Owners Manual in Oliver University.   The 2019 wiring diagrams are the most similar to 2021 models I have found. 

Edited yesterday at 03:09 AM by Hokieman
Added electrical diagram

[Dream Girl]

Great info as usual from the Oliver Tribe.  Thank you so much. Will check things out.   Mike