Alde Boiler Drain

Paul1959

Hello Everyone.  I have been working on winterizing my 2018 T@B 400.  We bought this used this year, so I am a newbie.  Now, I went through a plumbing drain process by opening each of the low point drains one at a time without opening any of the faucets.  I did the HW bypass and pumped in the pink antifreeze into the plumbing.  Afterwards I became concerned that I did not follow proper procedure as I see that in "Travels with Delaney" he opens up all of the low point drain simultaneously.  I have re-opened the drain for the boiler and get no water.  However, I am concerned that the water may be vacuum trapped.  I'd rather not have to drain out the antifreeze to start over.  Does anyone have any thoughts on how to tell if still water in the Alde boiler, or another method to insure drain of the boiler.  I spoke with NuCamp technical and the representative I spoke with said that simple opening the boiler drain is enough.  Is he correct?

Sharon_is_SAM

I think the only reason to open all the low point drains at once is to speed things up.  Opening a hot and cold tap may help speed up the low point drainage.  The AF will take care of any residual water.

The Alde manual says to open all the faucets and then open the Alde drain (to prevent a vacuum effect).  If you know that the Alde tank is full, it is a good idea to put a bucket under the Alde water tank drain to measure the output, then raise the tongue.  This will give you more confidence of adequate drainage, however, Alde has indicated that a little water left in the boiler tank will not harm the Alde if it freezes.  So, maybe try that next year.  

At this point, you can try raising the tongue and releasing the valve.  Alde instructions say to leave the drain valve open after draining, so that will help, too.

Paul1959

Hi Sharon,

Thanks for the response to my post!  I will give the tilt a try to see if effective.  Good idea.  If there is a vacuum lock, tilting may be enough to allow air into the system for additional draining.

Paul1959

Another thought occurred to me.  If I drain the plumbing to sort of re-start the process, would I necessarily need to Pump in antifreeze again?  I am thinking that I have effectively forced any water that was in the lines out through the fixtures. Having the low points drained, I believe that I would be able to break any vacuum and get any additional water out of the boiler.  

Sharon_is_SAM

You are assuming there is a vacuum and there is water in the boiler.  Personally, I would leave well enough alone knowing it is likely the boiler is adequately drained.  Just leave the Alde Safety/Drain valve open.

You are probably correct that water has been pushed out of the lines, but the point of the AF is to assure the absence of freezing if any water is left behind.  The  2 different winterization techniques calls for either completely saturating the plumbing with AF or thoroughly blowing out the lines.  If you drain the plumbing, you have lost the full protection of the AF that may have diluted unseen pockets of water.  If you have a problem in the spring, you won’t know what to pin it on.  Just my opinion, if you drain the AF, I would replace it.  Either way, in the spring, you will need to flush it thoroughly, so why not return the AF?

ScottG

I had a similar issue several years ago, and wrote about it here. 

I don't recall the specific order in which did things, but I know at the time I was not confident that the Alde was properly drained. 

I've since learned that the Alde can be drained thorough either the pressure relief valve (yellow flapper dohicky) or the regular low point cold water drain. At least that is how it works on my 320--the 400 may be configured a bit differently, but I think it works the same.

In my case, I had not added any antifreeze so that was not a confounding factor. Personally, I would take whatever steps necessary to convince myself the Alde is fully drained. Discovering come spring that you are the owner of a very expensive popsicle would be most unpleasant!

RCB

There is no problem if, after filing the system with AF , you loose some of the A F through a drain. I let as much drain out as possible. If there is some water somehow left in the plumbing, it is better to allow some pockets of air to develop to allow for expansion of any liquid that might freeze.

Paul1959

Thanks to all for your Thoughtful feedback!  Good to know that I am not alone in my T@B ownership experience!

Paul1959

Hello Everyone,

I thought that I would update you all on my winterizing drama.  Earlier this week, I decided to re-winterize as I found that I had used AF with Ethanol in it.  Should have done my research up front!  I also decided that I would use the Blue -100F stuff that has virgin polypropylene and NO ethanol.  Anyway, I flushed out the pink gooh and then drained the system.  Left it in bypass.  Then pumped out the water and did the one drain valve at a time procedure followed up opening up all three LPDs.  I did not get any more water out of the any of the drains by doing the latter.  Feeling confident that I had all of the water out of the boiler, I pumped in the new AF and thought that I was done.  Sharon mentioned leaving the boiler drain open per the Alde manual, So I decided to do this at my remote storage location.  At the storage location, the owner used a lawn tractor to back our camper into the winter resting place.  Before he did this I opened the boiler drain and some more water dribbled out.  Important to note that the tow vehicle positioned the tongue much lower than I had ,which was dead level.  We jacked up the tongue to tip the trailer back and got yet some more water out of the drain.  Tipped back down again and NO water.  So I leveled the unit up, and left the drain open per the recommendation.  I must admit that I am exasperated about this latest development.  I think in total I got perhaps 1/2 to 2/3 of a cup out with this event.  I would appreciate any feedback that folks can offer.

Sharon_is_SAM

@Paul1959 - it definitely helps to raise the tongue to maximize drainage of the Alde hot water tank.  Really the only way to have more confidence that your Alde tank is empty is to fill it, then place a bucket under it to confirm about 2.2 gallons is drained.  

After you flushed out the original AF, you may have considered filling the Alde water tank, then draining the plumbing and Alde tank again to get a measure.  So, you are back to not knowing if your tank is empty to your satisfaction.  

The Alde does have a non-return valve at the top where the hot water exits the tank (see letter C in photo).  That valve allows air into the tank which should lessen any vacuum effect.  If only a small amount of water is left behind, it will not hurt the Alde.  Just leave the Alde drain open.

Paul1959

Sharon and All,

I have some new information for you to consider.  I had a discussion on Friday with George at Alde.   The diagram that Sharon has supplied above shows the outlet connection for the boiler in illustration "C".  He pointed out that the air vent is the narrower connection. He also mentioned that the fitting is intended to be vertical with the air vent portion pointing up.  In my 2018 Tab 400, this is oriented horizontally.  Inside the air vent portion, there is a small ball that blocks the water from leaving when the tank is under pressure.  When the tank is drained, the ball falls down to allow air into the tank to enhance the drainage.  If the fitting is oriented horizontally, it may not perform as intended.  Also, this would explain why lifting an lowering the trailer tongue had an effect in that the ball moves back and forth allowing more air into the tank.  In my case, I disconnected the water line from the fitting and rotated the fitting into the proper orientation.  I did not get any additional water out.  I then blew air into the water fitting and blew out a couple of tablespoons of water, then only air came out.  So, it seems that my tank is almost totally empty.

George has submitted this issue to their quality control folks at Truma/Alde, which will eventually end up as a tech note at NuCamp.  I intend to address the issue in my unit come Spring.  I am going to re-orient the water line between the mixer valve and the Alde output such that the vent fitting is oriented properly.  Hope that everyone finds this information useful and insightful for your particular situation.

Regards,

Paul

ChanW

Paul, thanks for that info!

I have to say, I've never heard about that air-vent ball before now.

I know in my home hydronic system there is something similar that looks a lot like the "Automatic Air-Bleed" valve ('A' in the photos). It has a 'float-valve' that releases air from the system, but I never expected one in the hot water tee.

So now we find that the 'C' fitting as well as the 'A' valve are mounted w/ the wrong orientation by NuCamp... (In my 320 at least)... 

@Dalehelman said:

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.

We learn bit by bit, if we dig hard enough.

Sharon_is_SAM

Excellent info @Paul1959!  

So, “C” only works to prevent a vacuum when positioned vertically.  Good to know, but, your tank still emptied with it positioned horizontally due to changing the tongue position.

I am going to send this on to nuCamp.  This should be an easy adjustment.

Bayliss

WOW, @Paul1959 and @ChanW, what a revelation.  Here is a depiction of the correct orientation from the Alde manual.  My automatic check valve is also oriented horizontally, as depicted in the photograph below.  Crazy.

Yoshi_TAB

Hi,

I just want to double check something..so sorry if this has been asked before.

Before our last campout last week, I drained (tanks and low points ) and blew out all the water (because of anticipated freezing temps).  I did not open the yellow flapper at that time.  We used the alde heat which worked fine.  Today, to complete the winterization process, I went to drain the alde by opening the yellow flapper and nothing came out.

Did my previous process of draining (low point valves) and blowing out empty the alde?  I think it did, but wanted to double check why nothing came out.

Thank you

Sharon_is_SAM

Yes.  The cold water supply enters the bottom of the Alde.  When you drain the low point drains, the Alde water tank empties, too.
Check out ScottGs diagram found here:  

https://tab-rv.vanillacommunity.com/discussion/7856/plumbing-resources#latest

ScottG

Note that in the above diagram the "check valves" on both the hot and cold water lines near the Alde are NOT check valves but rather simple pipe reducers. This is indicated in the notes associated with diagram, but an update to diagram itself is. Still. Pending.  :-/ 

(That's why we put a disclaimer on resources provided by members--ha ha.) 

So, without a check valve, the Alde HW tank can be drained from either the yellow flap valve or the CW low point drain. 

Maxcamp

Thanks all for the helpful info and technical diagrams!

I've been dismayed at the lack of technical manual and on the phone with NuCamp several times to figure out winterizing and recommissioning as we travel.  Alde and other manufacturers' product data downloads never seem to match up with the actual NuCamp installation details.

I would not buy a truck that has no technical repair manual.  I hope we are all pressuring NuCamp to document their installations better.

T&B 320S Boondock mfg. Jan.2021 / Tacoma 4 cylinder pickup in low gears.

BrianZ

The Alde manuals I've seen, including at least two different ones online, plus the hard copy that came with our T@B, all show that hot water connector at an angle, but neither vertical as mentioned here, nor horizontal as installed by NüCamp.  It seems to me that if there was only a bit of a tilt, like shown below, that should get the ball rollin to allow air in for drainage of the tank..




Note that it states this is a check valve ("non-return") that also allows air in for drainage.
It seems to me that NuCamp's horizontal install should work too, unless the little ball inside were to get stuck in the closed position, versus having a bit of slope as shown here so that the default was in the open position.

Denny16

The little ball is the valve, and seats in a cone.  Pressure from,the water tank pushes the ball up to seat on the cone, preventing water from flowing out the air vent.  When the pressure from a full water tank is gone, the ball drops down, opening the air vent.  With the valve in a horizontal position, the ball is not being pulled back down by gravity and may jam.  At any angle greater than 45-degrees to vertical, the valve should work correctly. 
cheers