Changing out the Alde fluid.

fstop32

On my 320 w/3010 boiler the upper hose on the boiler is the output side (red dot on panel) and flows to and through all the convectors before going to the reservoir.  Coming off the reservoir the return hose hooks to the pump and then the lower input on the boiler (blue dot on panel).  @Tampakayaker I realize that didn't answer your question directly but I thought it might be helpful since you also have a 320 almost the same age as mine and can trace your hoses to and from the reservoir.

What I find encouraging is that we have owners trying out different ideas of changing glycol and sharing with the rest of us what worked and what didn't!  When I rebuild mine I've decide to add a 2nd drain on the passenger side and come up with a good way to bottom fill the system. I'm much more comfortable sitting on a 5 gal bucket than trying to perform a gymnastics routine to use the reservoir for anything beyond topping off my system 8^D

Tampakayaker

fstop32 said:

On my 320 w/3010 boiler the upper hose on the boiler is the output side (red dot on panel) and flows to and through all the convectors before going to the reservoir.  Coming off the reservoir the return hose hooks to the pump and then the lower input on the boiler (blue dot on panel).  @Tampakayaker I realize that didn't answer your question directly but I thought it might be helpful since you also have a 320 almost the same age as mine and can trace your hoses to and from the reservoir.

What I find encouraging is that we have owners trying out different ideas of changing glycol and sharing with the rest of us what worked and what didn't!  When I rebuild mine I've decide to add a 2nd drain on the passenger side and come up with a good way to bottom fill the system. I'm much more comfortable sitting on a 5 gal bucket than trying to perform a gymnastics routine to use the reservoir for anything beyond topping off my system 8^D

I guess I could disconnect what I think is the return hose, fire up the Alde and see if fluid squirts out all over the place! 

Horigan

qhumberd said:

I want to make sure I pump in the direction the system usually flows, so is the lower hose that @Horigan shows above the return TO the Alde or is that hose coming FROM the Alde to the tank? I want to pump thru in the normal direction of flow to not be blocked by the one way valve. Is the flow rate on this pump too high compared to the Alde pump?

Any comments welcome and I will post my pics and procedure list IF this is successful. 

The lower hose I attached the shop vac to is the flow INTO the reservoir.  You can confirm which hose flows into the reservoir by blowing into each of them.  There is a check valve in the system, so the hose into the reservoir will be blocked.  You'll want to attach your pump outlet to the other hose that you can blow into.

Denny16

Why not go ahead and use the new, improved Alde blue glycol, as long as you are going to do a water flush out.  Be sure to use distilled water for the second water flush.
cheers

Sharon_is_SAM

If there is Century fluid crystals under the hose, should there be concern with changing over to the Rhomar?  

qhumberd

Horigan said:

qhumberd said:

I want to make sure I pump in the direction the system usually flows, so is the lower hose that @Horigan shows above the return TO the Alde or is that hose coming FROM the Alde to the tank? I want to pump thru in the normal direction of flow to not be blocked by the one way valve. Is the flow rate on this pump too high compared to the Alde pump?

Any comments welcome and I will post my pics and procedure list IF this is successful. 

The lower hose I attached the shop vac to is the flow INTO the reservoir.  You can confirm which hose flows into the reservoir by blowing into each of them.  There is a check valve in the system, so the hose into the reservoir will be blocked.  You'll want to attach your pump outlet to the other hose that you can blow into.

Thanks for that clarification. Makes sense as that hose in your pictures was on vacuum and I will be pumping into the system. And the idea of the new fluid is a good one @Denny16 as well once I see how long it takes to get it here. Sounds like for the 400 I need 4 gallons. I'll get some pictures and see if I wreck anything. BTW my 400 build date was Oct 2018 so we are just beyond the 2 year point and it has been lightly used. I have had zero problems with all functions in my Alde and Alde flow thus far so wish me luck!

Denny16

Good luck @qhumberd! 
dheers

ScottG

Okay, as much as I prefer talking about work as opposed to actually doing it, after sixteen months of planning and discussion it was finally time to tackle replacing the original glycol in my 2015. 

The entire project ended up being more involved than planned because I wanted to inspect and mitigate potential corrosion in the convector loops in advance of the actual fluid change. I won't get into the details of that here, but if you are interested you can read about in this discussion.

My approach to this was not much different than that described by @gregndeb several pages back, so I won't rehash minutiae that has already been well detailed. The primary difference in my approach was the use of a simple hand-operated transfer pump. With a few minor wrinkles, I'll say this turned out to be stupidly easy...

The Equipment:

Two "gregndeb" adapters made from solid toilet risers and #2 drilled stoppers, three lengths of 3/8" ID x 1/2" OD tubing, two hose clamps, and an inexpensive transfer pump. (I chose this pump because it was clear and could be easily disassembled for cleaning.) The large bin was used to keep everything contained and mitigate spills. Total cost < $30.



Draining:

I think this step is entirely optional, particularly if the old glycol looks good and you have kept up with regular changes. Read on if interested, or just skip ahead to Filling.

1. Pull the drain plug under the T@B. Enter wrinkle #1. Contrary to past reports, only the contents of the reservoir tank (about a pint or two) drained before the flow stopped. 
2. Guessing there might be some sort of vacuum preventing the boiler itself from draining, I pulled the outlet hose from the top of the unit. (Use spill protection!) Things started flowing again and I got a full gallon drained.
3. As you know by now, the low point drain does not drain the glycol trapped in the convector loop. I recalled someone here talking about blowing into the system, and since the outlet hose was already disconnected, thought I'd give it a try...
4. I removed the section of hose containing the automatic air bleeder (which may or may not have been necessary), cleaned up the open end of the hose, and gave several good puffs. (Alternatively, I could have used the hand pump for this, as it also pumps air.) This forced the majority of the remaining glycol up into the reservoir, where it subsequently drained out through the low-point drain. I got another 2-1/2 quarts out this way. There may have been a bit of residual glycol left in the system, but not enough to lose sleep over.
5. Reinstall the drain plug.

Filling:

This was the easiest part...

1. Put the adapters into the reservoir tank and seat them firmly into their respective openings. The offset adapter connects to the pump outlet. The hose from the straight adapter runs into a drain bucket. The pump's inlet hose runs into your jug of fresh glycol. (See photos below.)
2. Start pumping. Enter wrinkle #2. My pump pumps mostly air. Seems it it works much better if I turn it upside down. Keep pumping. (My adapters stayed in place without my needing to hold them, so I could devote both hands to the pump.) 
3. If the system has been drained, nothing will drain from the outlet until you have replaced almost two gallons of fluid. Once glycol started flowing into the drain bucket, I kept pumping until I collected another quart or two.
4. If the system has not been drained, old glycol will be forced out ahead of the new glycol being pumped in. Pump until you have collected at least two gallons in your drain bucket. The hand pump is more than up to the task of moving the fluid through the system.
5. Remove the adapters, top up the reservoir, and replace the cap. Set the circulator pump speed as high as it will go, and turn it on (how you do this will depend on your particular pump and control panel). On high, the pump really moves the fluid and there should be quite a ruckus in the reservoir. Within a few seconds, a pretty large bubble burped out of the reservoir and the fluid level dropped. I stopped the pump and refilled. This happened one more time, and then the level remained steady.
6. Continue running the pump on high for several minutes. Once you are satisfied nor more air is escaping from the reservoir, you can turn on the heat. It will take a while for the glycol to warm up, but once it does, make sure heat is reaching all the convectors. If not, you may need to take additional steps to bleed the system. I didn't.
7. Turn off the system, return the pump its normal operating speed, adjust the level in the reservoir, and call it a day!

Here's a couple pics of the system in action. My system was drained so fresh glycol is not yet flowing to the drain bucket. 




 

ChanW

Great @ScottG, you finally got a round tooit! Nice and simple.

I like @tybladesmith's suggestion...

Replace the existing drain tee-hose fitting with the double tee, pinch in the middle, and push out the old glycol with the new, with a distilled-water flush in between.

My reservoir has a cap with a rubber seal in the cap, so with the vent hose outlet plugged, the reservoir becomes a sealed chamber with glycol and an air cushion in it....

I could do all the pumping and draining from outside the Tab...

Anyone see something I'm missing?

(do we have a direct source for Alde parts yet, or am I going to have to go through my dealer to order - the double tee Bottom Fill & Drain fitting - Alde part# 1900 876)

tybladesmith said:

@ScottG,  Alde bottom fill dual drain hose for bottom fill systems. ? Add this inline at a low point, clamp in-between and then drain/flush with distilled water before refilling with fresh glycol. Maybe even replacing the existing drain with a dual drain and fill under slight pressure to auto purge the air into the reservoir after the isolation clamp is removed using the onboard circulation pump. What do you think? 

fstop32

@ScottG  boy am I glad your situation was not a disaster!

Bayliss

@ScottG, excellent write-up of how to put the whole system together and draining the system.  Very helpful.  Kudos to you and @gregndeb for simplifying the glycol exchange process.

Can you clarify one point in #5 of the filling process?

• When you say "top up the reservoir," how high did you fill the reservoir with new fluid?  @gregndeb indicated that he filled the reservoir a little above "max."  Is that what you did?  (Am I correct in assuming that once the air bubble popped out inside the reservoir, that the glycol level ultimately settled to about the Alde recommended of 1/2" above the "MIN" line?)

Also, where did you purchase the hand pump?  And, were you able to purchase pre-drilled stoppers, or did you drill them yourself like @gregndeb did?

ScottG

@ChanW, I don't think you are missing anything--so long as you have an inlet and an outlet in close proximity, I doubt the system cares where you introduce and drain the glycol.

The advantage of the adapters is that you don't have to modify the system in any way. The advantage of the dual drain is that you don't have to construct adapters. Potayto, potahto...  :-)

No one has yet reported a reliable U.S. based source of Alde parts (though there are sources in the U.K.). It's not even clear if you can buy them from nuCamp via one of their dealers. (I was told a year ago nuCamp did not sell Alde parts.)

Alde U.S. claims they only sell parts in person at their Elkhart, IN headquarters. I have written a couple Alde "service centers" in the northeast regarding ordering and shipping parts and have gotten no response. I haven't pursued the matter further as haven't really needed any parts. I'm hoping someone else will solve this problem before I do.  ;-)

IIRC, don't you already have an extra drain fitting on hand? Why not just use that to make your own dual drain?

ScottG

@Bayless, I didn't pay much attention to the level as I was topping up, but I added quite a bit. Once the air burps out the level will fall dramatically, and I didn't want to inadvertently add more air by letting it get too low. Once the level stopped dropping, I actually had a little too much glycol in the tank, which I removed with turkey baster until I was down to the MAX line.

Here is the pump I used. I chose it for the reasons mentioned above. It's nothing special, and it does tend to pump a lot of air, but it got the job done.

EDIT: The pump ships with a LOT of clear grease on the plunger--you will want to wipe that off before running your glycol through it!

I drilled my own stoppers. You might be able to find pre-drilled #2 stoppers from a laboratory supply place, though I'm not sure if the standard hole would be big enough for the 3/8" risers. Maybe. A tight is better as it gives more leverage for fitting the stoppers firmly into the reservoir.

EDIT: Home brew suppliers (and why didn't I think of THAT) sell drilled stoppers. Here's one example! 

ChanW

@ScottG...
Regarding Alde parts sources, I contacted a parts site in Germany (or I tried to, with an apology for my lack of German - my German is not existent!)
Here is the reply (perhaps someone can translate!)
---------------------
Ihre Nachricht

   An: Constantin Kinias
   Betreff: Do you ship to the USA?
   Gesendet: Sonntag, 11. April 2021 22:10:08 (UTC+01:00) Amsterdam, Berlin, Bern, Rom, Stockholm, Wien

 wurde am Montag, 12. April 2021 07:24:23 (UTC+01:00) Amsterdam, Berlin, Bern, Rom, Stockholm, Wien gelesen.
--------------------

I'll take that to be a "no we don't ship to the US" 😁

ChanW

@ScottG,
OMG....
Re: Alde parts, I also received a reply from Alde/Truma!
Get this - there's hope!
---------

Good morning!

You can purchase this part directly from us. Give a call today or send shipping/credit card info via email and we can get the ball rolling!

Thanks!

Best Regards,

Chris Hoeppner

Customer Care Associate

t: 1-855-558-7862 x2120

e: c.hoeppner@trumacorp.com

CharlieRN

We just took delivery of our 2021 320 BD, so have will not need to worry about changing the fluid in the Alde system for some time. This thread has a lot of useful information, some of it pretty scary, but what provokes the most anxiety is access to the reservoir on the 320. Unlike the older models, the tank is behind the toilet so while it's pretty easy to visualize the reservoir to check the fluid level, access to it for something like a fluid change is very limited. 

On the plus side, I have almost two years to figure things out . . .

Tampakayaker

@ScottG, so you didn't remove the reservoir hoses, you stuck those tubes into them thru the reservoir cap opening? 

Pretty ingenious. 

It looks like your 2015 has the same setup as my 2016.  A screwed down top/ledge with outlets in it, then underneath an open area with a radiator, wiring, and the reservoir?

And I take it you could've pumped distilled water thru also if you want to?

fstop32

@ChanW you might be my ticket to rebuild parts!  I'll be sending Chris Hoeppner an email today...or maybe better yet a phone call - Thank you for that gem!

ScottG

@ChanW, nice going! Maybe Alde U.S. has finally settled in from the merge and realizes if they are going to stay in business they need to offer a reliable and simple source of parts.

Hopefully it is no longer relevant, but FYI WetWorks in the U.K. ships to the U.S. and even has a convenient U.S. storefront.

ScottG

@Tampakayaker, you are correct. The adapters designed by @gregndeb are based upon those used with the specialty Alde pump. They fit down into the top of the reservoir and stick into the inlet and outlet openings in the bottom of the tank. No awkward removal of the hoses necessary!

And, yes, you could use it to pump distilled water as well, if you were going to flush they system. (Note that if you are flushing the system in preparation for changing to the new fluid, you will want to use a lot of water. I put four gallons just through my boiler and was still getting tinges of green in the outflow. I think the boiler itself tends to trap a lot of fluid. This is less of an issue if you are just going to replace with the same stuff.)

Sounds like your T@B is configured the same as mine. Personally I like mine the way it is, as it is relatively easy to access and inspect everything under that shelf. Newer models incorporated side enclosures and cubby storage that i suspect makes access a little difficult.

And then there are the 2021 320s... @CharlieRN, it seems to me you could get those adapters down into that tank without too much difficulty. You could even make them a little shorter to facilitate things. Again, no removal of the tank or access to the hoses underneath should be required for a regular fluid change.

CharlieRN

@ScottG - great write up and I hope to use your technique when the time comes. Thankfully, I have plenty of time to play around with customizing things for the 2021 320. I have a hand transfer pump around somewhere and I'm a homebrewer, so may even have the drilled stoppers in my inventory!

ScottG

Sounds good, @CharlieRN!

As promised way back when in this discussion, at some point I'll trim my narrative down to a (hopefully) one-page instructional .pdf.

RDWHAHB!  ;-)
 

ChanW

Thanks for that link @ScottG, good to have a backup - though silly to have to order from Europe!

ScottG said:

........................
 FYI WetWorks in the U.K. ships to the U.S. and even has a convenient U.S. storefront.

ChanW

@ScottG, another question...

Since you needed to drain your system, and let in all that air, it didn't work the same as 'pushing out the old' with fluid.

Did you have a hard time ejecting the air, using your hand pump? I'd think it would tend to gather in the high spots.

I finally put together a diagram of our Alde system 'elevations', which makes it a bit easier (for me) to see why tilting and tipping doesn't get all the glycol out - i'd have to say it's impossible, without tipping the Tab upside-down!

Not sure how much use this sketch might be for others. The later Tab doesn't have the "Right convector" on the passenger side, like ours does.

Tampakayaker

ChanW said:

@ScottG, another question...

Since you needed to drain your system, and let in all that air, it didn't work the same as 'pushing out the old' with fluid.

Did you have a hard time ejecting the air, using your hand pump? I'd think it would tend to gather in the high spots.

I finally put together a diagram of our Alde system 'elevations', which makes it a bit easier (for me) to see why tilting and tipping doesn't get all the glycol out - i'd have to say it's impossible, without tipping the Tab upside-down!

Not sure how much use this sketch might be for others. The later Tab doesn't have the "Right convector" on the passenger side, like ours does.

So it looks like the underneath drain will only drain a little of the loop and mainly the reservoir. 

Our 2016 has the passenger side convector and the rear, not sure about the left side one, will have to look again.

I'm still debating about draining, then using a shop vac on the return line to the reservoir to get the old fluid out.  Maybe trying to suck distilled water thru to clean it out, then fresh fluid.

ReenieG

TabbyShack said:

I decided I will just be doing a partial gravity change every year and I just finished doing it for the first time.  Here is a photo of how much I was able to get out by raising and lowering the tongue. Each jug is a gallon. Since I over filled one jug and spilled about 1/8 cup switching out the jugs I'd  say this is closer to a gallon and a half. 

@TabbyShack did you need to do anything other than pull the drain plug and raise and lower the tongue?

I was exploring the option of doing this myself awhile ago, but then decided to see if any of the dealerships around me could do it with the pump. They don't, so I'm back to exploring this for myself, the way you did it. Did you purchase the full strength glycol?

I purchased the concentrate awhile ago but read something somewhere recently to dilute it 60/40 vs 75/25 which it states on the label.

I don't recall where the diagram was for the drain for the Alde glycol. Anyone?

Denny16

You should be able to push out the old fluid, by draining the reservoir, disconnecting the return hose to the reservoir and put it in a bucket,  then fill the reservoir with new fluid,.  As the reservoir drains, keep filling it until you collect all the old fluid in the bucket.  If you know the total volume, collect this amount and then a bit more, and you should,have replaced all the fluid and purged the system, without introducing a lot of air.  

To reduce air getting in, crimp the return hose in the Alde side of the low point drain, add new fluid to the reservoir, open the low point drain until the new fluid runs dour, whilst adding more (two person job), once air is purged, remove the clamp on the return line to the boiler, and as the level in the reservoir drops, keep adding new fluid (a pump in a galling jug or syphon would work to keep the reservoir filling.   Just a thought... 

cheers

Tampakayaker

Denny16 said:

You should be able to push out the old fluid, by draining the reservoir, disconnecting the return hose to the reservoir and put it in a bucket,  then fill the reservoir with new fluid,.  As the reservoir drains, keep filling it until you collect all the old fluid in the bucket.  If you know the total volume, collect this amount and then a bit more, and you should,have replaced all the fluid and purged the system, without introducing a lot of air.  

To reduce air getting in, crimp the return hose in the Alde side of the low point drain, add new fluid to the reservoir, open the low point drain until the new fluid runs dour, whilst adding more (two person job), once air is purged, remove the clamp on the return line to the boiler, and as the level in the reservoir drops, keep adding new fluid (a pump in a galling jug or syphon would work to keep the reservoir filling.   Just a thought... 

cheers

Is there a check valve in the return port of the reservoir, or do you need to plug the port since the return hose is off?

ReenieG

@Denny16 there's only one of me, so...

I'd like to do the KISS method and will live with only replacing what drains out, sort of like @TabbyShack did.

Thanks for your thoughts, btw.

Denny16

In that case, you may need to do this more often, maybe at the end and start of each camping season, to keep purging the old fluid out and replacing it with new fuild, as yiu are mixing the old and new together.  Not an ideal situation.  

You could get a 3-gallon bucket, add a hose barb fitting to the bottom of it and connect  this hose to replace the connection from the reservoir.  Then you have 3-gallons to allow the Alde pump, set on high and continuous, to pump from the 3-gallon bucket of new fluid into the system. with the return line to the reservoir connected to an empty bucket to collect the old fluid.  This would be a one person setup.
cheers