Doing more that topping off the glycol tank - 2021 T@B Boondock

geoB

I finally got around to reading up on dealing with glycol for the trailer we've had for 4 years. Did the Convector Tour on mine to get the distinct impression that all is well. My current thinking is to gear up to be able to replace a gallon of glycol every year.

Pros? Cons?

And thanks!

qhumberd

We have had our 2019 400 for 6 years, and mainly camp in the Southeast region. I have flushed and refilled the system twice and have not noticed the need to add glycol in the interim.

Perhaps drier regions have evaporation from the reservoir?

MuttonChops

I'm one of those that just does the 1-gallon gravity drain 'refresh' every few years not every year and my Alde system seems to be doing fine. Plus I frequently do a winter months trip of 4-7 weeks with Alde on everyday.

Living in the dry west I do have to add 1-3 cups of glycol mix to the reserve tank each year.

pthomas745

Lots of owners have done a "drain and replenish" or "refresh" that MuttonChops mentioned.

The thinking goes that what we are really "replacing" or "refreshing" is the roughly 3-5 percent of the glycol that are the "anti corrosion" chemicals. Since we already have a lot of experience that shows us that the "corrosion" is happening under poorly clamped and "bare" aluminum parts. Improving the clamping and coating the stub ends of the convectors could prove to be a better solution to the corrosion issue than 800 dollar "glycol changes".

Other owners have discovered the way to get the majority of the glycol out of the trailer with simply applying pressure at the "check valve" that sits next to the Auto Air Bleed Vavle. In my 2017, this worked quite well for me, since the 2017 expansion tank is difficult to get to. This is the original comment about this method in the "Changing out The Alde Glycol" thread.

https://tab-rv.vanillacommunity.com/discussion/comment/165276#Comment_165276

This method can also be found in the Appendix A of the DIY Glycol Change document posted here:

Diy Glycol Exchange

manyman297

I’m overdue on my glycol exchange but how are you all doing the gallon drain and fill? Just remove drain clamp under the trailer and fill the reservoir? I’m assuming you may want to run the pump a bit to bleed any air?

pthomas745

@manyman297 If you follow along with that "pushing the glycol out from the check valve" thread above, you will be removing more than half the glycol from the trailer. After that, the procedure is the same as if you removed all the glycol or or pumped through new glycol: See the "DIY Glycol File" Appendix A, and follow that procedure. When you go to refill the glycol tank after pushing out as much glycol as you can, then put the valve back in place, put the glycol drain plug back in.

Then go to "Step 7" on page 6, where the sentence "Top up the expansion tank with fresh glycol…." and follow the rest of the procedure with the glycol pump sending glycol around the system and "burping" the majority of the air from the glycol.