Winterizing with RV Antifreeze

teztab

I've tried searching for a specific answer to this question, without success, so I'm hoping for helpful enlightenment from the Tab cognoscenti:

I'm about to winterize for the season and being in a region where we can have brutally low temperatures I've decided to run RV antifreeze through the system.  The Tab manual seems to suggest bypassing the Alde boiler once drained, therefore preventing antifreeze entering the boiler.  This also appears to be the recommendation of other sources I have read.  However, the Alde manual does not appear to suggest avoiding antifreeze in the hot water boiler, in fact if I am reading it correctly it seems ok with doing so (no, I am not confusing the hot water boiler with the heating system ☺).  So, do I run antifreeze in the boiler and, if not, why not?   Thanks in anticipation...

ChanW

Yep, the various info on this has been contradictory at times. 

Way back in 2014 or so, Alde came out with a recommendation that the fresh water heater jacket should not be exposed to antifreeze. They said it had something to do with the rubber seals not reacting well to the heated RV antifreeze. (I think previous to that they'd said it was no problem having antifreeze in contact with the hot water system. My guess is that it was a cautionary 'just-in-case' recommendation, maybe because they had little experience with US brands of RV antifreeze.) 

The announcement was kind of a drag for us, because we'd already winterized with antifreeze in the hot water system (there was not a bypass system on the early Alde Tab system), and we'd gone ahead and use the Alde with it winterized, doing some winter camping. (We've since stopped using the antifreeze method for winterizing the pipes!)

At any rate, the latest word is to not allow hot antifreeze in contact with your fresh water heater jacket. Thus the bypass valve system was incorporated into the Alde system design.

teztab

ChanW said:

Yep, the various info on this has been contradictory at times. 

Way back in 2014 or so, Alde came out with a recommendation that the fresh water heater jacket should not be exposed to antifreeze. They said it had something to do with the rubber seals not reacting well to the heated RV antifreeze. (I think previous to that they'd said it was no problem having antifreeze in contact with the hot water system. My guess is that it was a cautionary 'just-in-case' recommendation, maybe because they had little experience with US brands of RV antifreeze.) 

The announcement was kind of a drag for us, because we'd already winterized with antifreeze in the hot water system (there was not a bypass system on the early Alde Tab system), and we'd gone ahead and use the Alde with it winterized, doing some winter camping. (We've since stopped using the antifreeze method for winterizing the pipes!)

At any rate, the latest word is to not allow hot antifreeze in contact with your fresh water heater jacket. Thus the bypass valve system was incorporated into the Alde system design.

Many thanks, at least I can feel relieved that my confusion is not of my own making!  So I guess I should take the cautionary approach and bypass the boiler.  Of course I'll need to be doubly sure the boiler is fully blown out...

ScottG

I'll emphasize ChanW's comment that the concern seemed to center around heating the antifreeze--i.e., using the Alde for cabin heat after the supply plumbing had been winterized.

If like most of us you are just winterizing and not planning to used the camper again until you've de-winterized in the spring, there is probably even less concern.

That said, I don't know of a compelling reason to fill the Alde with antifreeze. It'll cost you an extra three gallons and create that much more flushing work in the spring. If you've emptied the tank and blown the lines, even a little residual water won't expand enough to crack anything.

teztab

ScottG said:

I'll emphasize ChanW's comment that the concern seemed to center around heating the antifreeze--i.e., using the Alde for cabin heat after the supply plumbing had been winterized.

If like most of us you are just winterizing and not planning to used the camper again until you've de-winterized in the spring, there is probably even less concern.

That said, I don't know of a compelling reason to fill the Alde with antifreeze. It'll cost you an extra three gallons and create that much more flushing work in the spring. If you've emptied the tank and blown the lines, even a little residual water won't expand enough to crack anything.

Thanks, again.  I am now beginning to wonder whether I should run antifreeze through the system at all (just use it in the drains and traps).  My first concern was having enough of an air pump to blow out any residual water in the pipes (I will be using a volume air pump rather than a high pressure pump).  However, the schoolboy scientist in me reckons that even if there is a dribble of  water left in the system, none of the pipes will be filled and under pressure therefore any water expansion caused by freezing should not be a problem.  If the pipes were copper rather than pex, of course,  maybe I'd be more concerned...

ScottG

FWIW I also live in a deep-freeze zone and have relied solely on the blow-out method. I do blow things out pretty thoroughly with a high-power electric compressor, but it's probably overkill and I know others have winterized successfully with manual pumps. I agree with your schoolboy scientist that residual water is no more a problem in the supply plumbing than it is in the Alde.

I do take care to blow out all of the fixtures one by one (including the toilet), and I make sure there's antifreeze in all the traps and on the gate valves for the the black and gray tanks. I also run a little antifreeze through the pump, though there's nothing suggesting that that is necessary or makes any sort of difference. It's just my little AR thing I like to do.  :-)

 

teztab

Many thanks, ScottG, that's reassuring and very helpful!

cgstarry

I’m glad to see you asking this Teztab.  I was wondering the same thing.  How much water did you get when you drained your boiler?  I got two gallons but expected about a half gallon more from my 3010 based on a lot of what I see documented here...  

teztab

cgstarry said:

I’m glad to see you asking this jTeztab.  I was wondering the same thing.  How much water did you get when you drained your boiler?  I got two gallons but expected about a half gallon more from my 3010 based on a lot of what I see documented here...  

I did drain the boiler yesterday, but really did not pay attention as to how much water escaped.  Plus, I've yet to blow air through the system.  However, once again I'm confused by both the Nucamp and Alde manuals!  I drained the boiler by releasing the pressure relief valve and opening the hot water drain valve but I'm unable to identify the boiler drain valve to which they refer!  Does that exist and where should it be on my Alde 3010?  Thanks!

dragonsdofly

@teztab, we do the blowout method with rv antifreeze only in the shower and sink traps, toilet gasket, black and gray tanks and black and gray gate valves. My husband uses only a manual bicycle pump and it works well enough to have made it through 2 Michigan winters, now heading into the third. He does disconnect the water pump and pays special attention to getting water out of the toilet valve and inner works, which is probably the most vulnerable area and most often forgotten about. Good luck. It's easily doable. Take your time and be thorough. And there's a lot less to do in the spring getting the pink stuff out of the freshwater system.

ChanW

I'm not sure I can see what year you have, but our 2014 doesn't have that extra Alde drain valve. All we have is the drain valve on the hot water line and the drain valve on the cold water line. Plus the FW tank drain.

I agree with @dragonsdofly. Getting the antifreeze out of the fresh water lines in the spring is a real chore. (Unless you use vodka!)

ScottG

teztab said:

...

However, once again I'm confused by both the Nucamp and Alde manuals!  I drained the boiler by releasing the pressure relief valve and opening the hot water drain valve but I'm unable to identify the boiler drain valve to which they refer!  Does that exist and where should it be on my Alde 3010?  Thanks!

The only "boiler drain valve" I'm aware of on the 3010 is the yellow handled flapper thingy.

There is another drain for the glycol in the cabin heating loop (it's just a plug, not a valve) but you don't want to open that one!

teztab

Once again, thanks to all for the help!

ScottG

ChanW said:

I'm not sure I can see what year you have, but our 2014 doesn't have that extra Alde drain valve. All we have is the drain valve on the hot water line and the drain valve on the cold water line. Plus the FW tank drain.
...

So @ChanW, do you just drain your Alde back through the regular CW drain? Seems that should work the same way.

The only potential detriment I can see to not having the yellow flapper valve is that you don't have any automatic means of releasing excess system pressure.

ericnliz

@ScottG, Isn't that what the toilet is for???

ChanW

@ScottG, yeah, I've never had a problem with draining just through the two drain valves. Someone once suggested here that there was a system 'backflow' prevention device in there somewhere, but I've never seen any indication of it.
I'm not at our Tab right now, but I think I remember there's a pressure relief valve in there somewhere, just not the pretty yellow multi-purpose one that others have.

ScottG

@ChanW, that might have been me who mentioned the check valve. In my case it's installed just ahead of the yellow flapper valve, so I can see where you might not have it if you don't have the valve.

ScottG

@ericnliz, biologically speaking, I guess it does work pretty much the same way...  :-)

ChanW

@ScottG, our pressure relief valve (I think!)

rajamar

Yes, here's a pic of the glycol reservoir, hot glycol, and hot water overflow/pressure relief lines converge and exit through the floor. (red arrow, NOT where finger is pointing.) 2016 320S

ScottG

ChanW said:

@ScottG, our pressure relief valve (I think!)

Yep, I've got one of those, too, in addition to the yellow flapper valve. I also take it to be some sort of pressure relief valve, but I'm not sure why they system needs two, or why the yellow valve was apparently added as an afterthought.

Camperforlife

This may be a silly question but I'm new to winterizing my tab and I've been reading these posts trying to learn as I go. If I'm understanding correctly a lot of owners are draining both the hot water tank and the heating system tank and lines of the alde 3020 when winterizing. The heating tank and lines are filled with propylene glycol/water mixture. Wouldn't this be safe to leave in year round since it will not freeze?

CoriJ

What is the yellow flapper valve???  Do you need to release that one to when winterizing?

Sharon_is_SAM

@Camperforlife, you do not drain the Alde glycol.  You drain the Alde hot water tank.  This may be helpful. More manuals under Categories:  User Manuals/PDFs.

https://us.v-cdn.net/5021717/uploads/editor/f4/n58uymbo6aav.pdf

Sharon_is_SAM

@CoriJ, see attachment above for how to winterize.

ScottG

Yellow flappers were commonly installed in 1920's vintage T@Bs...

ScottG

Oh, that yellow flapper...  ;-)

@CoriJ, you'll find the yellow flapper valve in the cold water (blue) line leading into the bottom of the Alde. This diagram (from the Alde manual) shows what it looks like and how to tell if it is open or closed.

Alde says to use this to drain the internal HW tank. nuCamp's instructions claim you don't need to use it to winterize, but many of us do. I figure if you have a drain, then you might as well open it. You sure don't want to leave that tank full of water over the winter!