Changing out the Alde fluid.

Tabaz

BrianZ and ChanW - here is the funniest colonoscopy essay ever:
https://www.gastronj.com/wp-content/uploads/2011/02/Dave-Barrys-Colonoscopy.pdf

Tabaz

Maybe we can dispense with the whole pump, tubes, etc. by simply removing the drain plug and putting some "MoviPrep" in the overflow jug and letting nature take care of the rest.

ChanW

Ha! Leave it to Dave Barry!

BrianZ

Thank you for that, @Tabaz.  Dave Barry is hillarious.  I had trouble reading it at one point from the tears in my eyes from laughing.

fstop32

I just experienced a sudden urge to....

ChanW

It probably must be said though, it's not a good idea to drink the Tab's glycol, no matter what ailment you might be worried about contracting! (Nor the Lysol!) 

(Uh oh... This might bring the wrath of the wand...!)

 Tabaz said:

BrianZ and ChanW - here is the funniest colonoscopy essay ever:
https://www.gastronj.com/wp-content/uploads/2011/02/Dave-Barrys-Colonoscopy.pdf

tybladesmith

@Tabaz , thanks for the laughs. Each time I get a colonoscopy the prep changes but it is also getting easier, thanks to people like Dave Barry. He left out the part about every popcorn hull you have ever eaten! but as my kids say - TMI.

Sharon_is_SAM

Ok, I couldn’t resist.  Since this thread has gone sideways anyways.  This is the funniest...

https://youtu.be/gHiaMXM70Ms

Tabaz

Maybe Scott can combine these recent colonoscopy posts with the "Ketchup on Hot Dogs" discussion? 

Tabaz

OK, back to our movie . . .  Just completed the system flush using Scott's recommended equipment and process.  SUCCESS!  With only one comment.  My toilet tubes did not want to stay in their holes in the overflow tub, so I had to hold them down with my right hand while holding the pump body and using my left hand to use the plunger.  While laying on my side.  WAY too much work.  Next time I'll try the submersible pump idea or get softer rubber stoppers that will stay in the holes without having to hold them in (or both).  Flushed-out the system using 8 gallons distilled water.  The waste water was crystal clear, indicating a very clean flush.  Will put the new fluid in tomorrow morning.

ScottG

While we are on the topic of moving lots of fluid and gas, I went out to do more springizizing today and fired up the Alde circulator just to be sure all was well. A few more bubbles seemed to be finding their way into the expansion tank--I assume this was a little trapped air that had worked its way up since the exchange. I increased the pump speed for a few minutes to facilitate the burping, and when I turned it back down all was back to normal. Just something to keep in mind if you do this exchange--it may take a few run cycles to purge all the air.

@Tabaz, thanks for the report. I was surprised my stoppers stayed in as well as they did, but I expect that will not always be the case. In the instructions I suggested an extra set of hands may be needed for this step. I think you demonstrated why.  ;-)  Let us know how the final fill and air bleeding goes tomorrow.

@lkc001, prompted by your recent question, I staged a better photo of the adapters in the expansion tank. I'll incorporate it into the next revision of the instructions. Keep in mind the adapter could be made quite a bit shorter if needed because of low clearance above the tank.

 

lkc001

@ScottG LOL springizing— Thank you for clarifying—so I went back out to the trailer & all thoughts of me being able to do the complete drain @ exchange went out the window— I do not have even enough room above the expansion tank to get my head in far enough to be able to look down into the tank to place the adapters in the right place— it would take a complete removal of the wall that the tank is attached to.  I don’t know how a service person would do it either so if I ever find anyone that says they work on the Alde I’ll have to be asking a lot of questions before I let them touch it.  Too bad a shop vac doesn’t have enough suction to pull all the fluid out at the drain under the trailer.  Back to square one for me!  Im waiting for calls back from a couple more places.

Sharon_is_SAM

@lkc001 - is this where your tank is located?  Does it help to open up the entire shelf back there?  Is it possible to unbolt the tank from the wall?

BrianZ

I can sympathize with you, @lkc001.  Ours is like yours/Sharon's, so a bit difficult to access, while Scott has an earlier model with better access.  That's why I plan to try a different route using a T-valve & the drain to flush & add new glycol.  I'm still waiting on some backup parts to arrive before I can get started.  I'll still need to monitor that tank, but I'm going to try using my cell phone to view it remotely, if possible.
You mentioned a shop vac not having enough suction to pull fluid out the drain.  Has this been tried?  I'm not sure its strength would be as much of an issue as the check valve interfering, and depending on which direction you're trying to draw out the fluid, pinching closed the air & overflow tubes on the tank.

Tabaz

Before I used Scott's toilet riser method, I attempted to flush the lines using the hand pump attached to the inlet and outlet Alde hoses.  I was unpleasantly surprised when the overflow tank began filling up.  It would have overflowed into the cabin had I not stopped the process.  Be careful using any method that adds fluid without bypassing the overflow tank.

BrianZ

I have a theoretical question for anyone with a basic understanding of the flow in the Alde glycol plumbing (the simpler one like our 3010 model)..
If I am injecting fluid through a T-valve into the hose between pump & drain (but closed between valve & drain, such that the drain only drains from the expansion tank); should I pinch closed one or both of the tank's small hoses at top of expansion tank (air hose & overflow hose), or leave them open?  I was thinking that might force fluid in the tank to drain better/faster in a system under a bit of pressure from a pump pushing fluids in (although if the line exiting the tank got plugged somehow, that could be a problem).  Maybe I'm overthinking this, but I was just concerned that pumping fluid into the system might exceed the rate at which it normally drains by gravity from the tank, requiring closer monitoring of tank level.  On the other hand, that's why there is an overflow tube, so maybe I only need to make sure the drain bucket under the Tab is under both drains.

lkc001

@Sharon_is_SAM. That is where mine is— I would not attempt to unscrew the clamps that hold it onto the wall because I don’t know how the hoses on the bottom of the tank are attached nor if there is any play in the lines to move the tank around.  Opening up the lid on the long storage cabinet actually impedes access to that corner even by more— I don’t see how a serviceman is going to get in there either 

lkc001

@BrianZ  no I don’t think it’s been tried— it was just wishful thinking it could be that simple!

ScottG

@BrianZ, I follow your logic, but pressurizing the expansion tank strikes me as a recipe for a potential mess. I suggest focusing on pumping fluid at a rate that does not exceed the drain off capacity of the tank. One of the reasons I gravitated toward a manual pump is I know it it wouldn't get out my control. YMMV.

BrianZ

Thanks, @ScottG, you're probably correct about doing it as safely as possible, but my intent is not to pressurize the tank in a static sense, but only very briefly beyond the minimal required to start the tank draining, which gravity is already assisting with.  Alternatively, l am also thinking that clamping just the tank's short air hose may be a safer alternative, since that is the only route that glycol could potentially exit the tank into the cabin.  Plus there would still be two drains connected to the tank that both lead outside under the T@B - the main drain line at bottom plus the overflow drain line at top of the tank.  No matter how you pump or at whatever relatively slow rate, it seems to me that for this purpose it makes sense to plug the air vent during flushing.  On the other hand, unplugging the air vent is necessary in normal use to avoid creating a vacuum in the tank that could prevent fluid from draining or settling.  Agree that monitoring the tank level is very important & the only way to know what's happening in this scenario. Thanks for your feedback.

Another question for you, @ScottG, about when you first disconnected & blew out the top hose from the Alde & had no leakage of glycol from the disconnected hose..  After reviewing @ChanW's elevations drawing, it would appear that you would have needed to keep that end of that hose at least as high as the expansion tank level to avoid fluid from flowing out - is that correct?  In his drawing, that exit from the Alde is substantially lower than the tank.  Granted, there is the check valve preventing backflow, but you said you had removed it, so wondering still what to expect when I try this maneuver.  Maybe it would be best to remove only the air bleeder but not the check valve, if possible.

ScottG

@BrianZ, no argument that everything you suggest should work fine, just that these steps are not necessary if you are not already courting disaster by pumping fluid faster than gravity can drain it. And--as you noted--plugging the air vent could actually reduce the rate of draining from the tank. This is why DWV system in your house (and T@B) have very specific venting requirements.

And yes, you are correct that if you remove the heater hose at the top of the Alde, the end should be kept higher than the bottom of the expansion tank (which should already be drained) to prevent any excess dribbling while there is still fluid in the convector loop. I mention this in Appendix A of the instructions I posted.

Unlike newer models, my check valve is integrated into the hose that also includes the air bleeder. Even if it was separate, I would have still removed it before blowing the lines. It's not that hard to keep the hose sufficiently elevated long enough puff out the residual glycol.

BrianZ

Thank you, @ScottG.
What I said was "..unplugging the air vent is necessary in normal use..", but pumping glycol into the system with the drain valve open is not normal use.
I thought that with a separate check valve, leaving it in might be good insurance against a backflow spill from the convector loop when disconnecting.  On the other hand, with the apparent unavailability of Alde parts, T@B owners & DIYers in particular are in a bind right now that could make maintenance very expensive and/or inconvenient if a critical part gets damaged, though it seems like the risk is minimal with gentle pressure.

TNOutback

I reached out to Alde to seek their advice since I am coming up on my 2 year interval for changing out the glycol, asking if I should continue with the Century or switch to the Rhomar product.  This was their reply:

We would highly recommend that you have the unit flushed and new Rhomar glycol put in it. the Rhomar has a higher level of corrosion protection and is what we would suggest using. 

Thank you, 
Chantal 

Best Regards,

Chantal Hershberger
Senior Customer Care Coordinator

ScottG

BrianZ said:

...
What I said was "..unplugging the air vent is necessary in normal use..", but pumping glycol into the system with the drain valve open is not normal use.
...

@BrianZ, I was only addressing your specific question of May 9, based upon my knowledge of the flow of the glycol, my original thoughts for the "filling tee" approach, and my personal experience.

When I pushed fluid up into the open expansion tank, it quickly drained away via gravity. This normal draining process is the same regardless of whether or not you are pumping glycol (or air) into the system from another location.

I do not see an advantage to clamping the air vent and overflow lines, I surmise that doing so could even impede normal drainage, and I do believe you are overthinking this.  ;-)

pak

I'm going to use the manual pump method. Filling using the return line will hit the pump from the correct side. Not knowing the pump design I want the slow motion of the hand pump to feel how fast the fluid passes through the pump.

ScottG

@pak, I also like the sense of "feel" the manual pump affords. I was surprised how little resistance there was, even when the system was full. It was good to know I wasn't forcing anything.

The biggest drawback I can see it that it requires three hands to run the pump and hold the adapters in place (if necessary). The great @Tabaz seems to have accomplished this task. I had hoped with his forth hand he might have taken a photo of his contortions so I could include it in the next update of the glycol change instructions.  ;-)  

pak

I completed my change out with the addition of the new glycol today. I drilled a hole in one of the caps to hold the draw line in the fluid. I too found very little resistance, if any, at the pump. I could have easily filled most of the system with just gravity. I went slow and chased out most of the air on the fill. Running the pump got the rest. I suppose driving down the road will reposition or evacuate any air that may be hidden. My system took a little over 7 quarts. I will monitor the res tank to see if additional fluid will need to be added. Thanks to all for the ideas and clever make shift tools. This cooperative forum saved a lot of head scratching not to mention time and money. 

Dalehelman

@pak
What model and year is your Tab? How many connectors?

BrianZ

In regards to my 3-way valve idea shown on page 19 of this topic, I did some temperature testing of my PVC barbed hose connectors, and became less confident they would hold up unless the glycol returning from the expansion tank would remain below about 170°F.  At around that temp, the PVC fitting began to soften, and at 180° I could squeeze the barbed tip between my fingers & it would deform into an oval shape.  They were a good fit for the Alde 22mm rubber hose, while the 3/4" stainless steel  barbed fitting was too loose for Alde's 7/8" ID hose, but there was a solution..

On a more positive note, and thanks to @rh5555's valuable message over in the parallel corrosion topic, I learned that heat shrink tubing (like that used for electronics wiring) can be used on fittings under hose connections.  What a revelation that was for me!  I got out my heat shrink tubing kit, and found the 20mm x 60mm size was a perfect fit for my 3/4 stainless steel barbed fitting, and cutting in half gave me two layers of just the right length..

The fact that it shrinks around the barbs make them stay on without slipping off when the hose is removed, so is a perfect fit now for the Alde 22mm rubber hose..

The fit that was previously loose is now nice & snug.
Next, I'll need to repeat my pressure test for leaks.  The valve is stainless too, so no issues with mixed metals.  This are looking a bit more promising now for my glycol fill valve.  I think this heat shrink tubing idea for fittings like this is a real winner.
5-13-21 Update:
I repeated the leak test as previously described, using15 PSI of air pressure connected to the water-filled valve, and there were no leaks from the rubber Alde hose at the barbed fittings with heat-shrink tubing added, using one standard Alde pinch type hose clamp.
As before, the threaded connection of the barbed fitting to the valve body required some extra teflon tape & tightening to eliminate a couple of very tiny drops that appeared after 5 mins.  No leaks after that.

Dalehelman

I understand that the auto air bleed valve must be in a level position to work properly. As they come from the factory they are not in the proper position. It should be resting in the white cradle. The problem I the top of the valve hits the underside of the seat cushion. 

Solution is to carve out enough material from the bottom of cushion to allow proper clearance. A large Forstner drill bit would work well.