Descaling the Seawater Lines


Dean Gillies
 

Hi all,
I'm preparing Stella for in-water wintering in southern Spain and will be filling all seawater lines with freshwater as I've always done in the past for non-freezing winterisation.  

I'm wondering about the wisdom of treating the seawater lines with some kind of de-scaling treatment. I've previously cleaned my ONAN heat exchanger with dilute Hydrochloric Acid (Muriatic Acid) but that seems a bit over the top to flush right through the seawater systems. I know some folks like barnacle buster and such-like.  I don't have any symptoms of poor water flow anywhere, so my gut feel says "if it ain't broke ...".  Am I missing something?

Cheers
Dean
SV STELLA
A54-154
   


Nick Newington
 

Hi Dean,
I just flush with fresh water and then use some antifreeze in the mix and let it sit. It has good anti corrosion properties. I do this for the engine and generator and the aircon and fridge cooling. The watermaker gets it’s sodium metabisulphate solution.

If there are crustaceans in the cooling then clearly it will not dissolve the shells..

Nick
S/Y Amelia
Leros and hauling out tomorrow

AML54-019

On 8 Nov 2021, at 16:42, Dean Gillies <stella@...> wrote:

Hi all,
I'm preparing Stella for in-water wintering in southern Spain and will be filling all seawater lines with freshwater as I've always done in the past for non-freezing winterisation.  

I'm wondering about the wisdom of treating the seawater lines with some kind of de-scaling treatment. I've previously cleaned my ONAN heat exchanger with dilute Hydrochloric Acid (Muriatic Acid) but that seems a bit over the top to flush right through the seawater systems. I know some folks like barnacle buster and such-like.  I don't have any symptoms of poor water flow anywhere, so my gut feel says "if it ain't broke ...".  Am I missing something?

Cheers
Dean
SV STELLA
A54-154
   


Dean Gillies
 

Thanks Nick. 
What you do is pretty much what I've done previously. I've been using the pink "Starbrite" anti-freeze.

We had a great passage down here from Scotland and the boat performed superbly.  Brexit and VAT concerns have now dissolved into the warm breezes of the Med :-)

Good luck with your lifting tomorrow.
Cheers, Dean
 


Mark McGovern
 

Dean,
 
While I am usually an advocate of the "if it ain't broke don't fix it camp" I will advise you to preventatively address at least one of your heads if at all possible.  Either by treating it to reduce scale or by just replacing the hoses outright.  I say this because I had one head clog up within a few weeks of moving aboard full time earlier this year.  Changing out the hoses out when they are filled with shit-water is just about one of the worst jobs I have ever done on a boat.  Certainly the "shittiest."  Taking the hint, I pre-emptively replaced the hoses on the other head soon thereafter.  Here is what the cross-section of hose looked like on the head that I changed out BEFORE it stopped working:



The 38mm ID hose had a true ID of maybe 20mm.  And yes, that is a tampon shoved up inside the hose.  The hose was so stiff from all the calcification that I had to cut the hose into several sections in order to remove it.  Tampon did a great job absorbing the residual bleach water that was in the hose.

For fun, I knocked some of the "chunks" out and dropped them into some cups of regular white vinegar, some "industrial strength" white vinegar, and several different dilutions of 85% Food Grade Phosphoric Acid that I have onboard.  Phosphoric Acid is the active and main ingredient in products like Barnacle Buster/Sew Clean.  It's also an ingredient in many soft drinks like Coke. The vinegars had no effect on the calcium whatsoever.    The Phosphoric Acid dissolved the scale when diluted with water as much as 7:1, albeit slowly.  A 5:1 dissolved large chunks quickly.

Hope this helps!

--
Mark McGovern
SM #440 Cara
Belfast, ME USA


Nick Newington
 

Hi Mark,
As a matter of interest are you using sea water or fresh water for the flush?
Kind regards
Nick
S/Y Amelia 
Leros
AML 54-019


On 8 Nov 2021, at 18:59, Mark McGovern <mfmcgovern@...> wrote:

Dean,
 
While I am usually an advocate of the "if it ain't broke don't fix it camp" I will advise you to preventatively address at least one of your heads if at all possible.  Either by treating it to reduce scale or by just replacing the hoses outright.  I say this because I had one head clog up within a few weeks of moving aboard full time earlier this year.  Changing out the hoses out when they are filled with shit-water is just about one of the worst jobs I have ever done on a boat.  Certainly the "shittiest."  Taking the hint, I pre-emptively replaced the hoses on the other head soon thereafter.  Here is what the cross-section of hose looked like on the head that I changed out BEFORE it stopped working:

<IMG_20210612_180500841.jpg>


The 38mm ID hose had a true ID of maybe 20mm.  And yes, that is a tampon shoved up inside the hose.  The hose was so stiff from all the calcification that I had to cut the hose into several sections in order to remove it.  Tampon did a great job absorbing the residual bleach water that was in the hose.

For fun, I knocked some of the "chunks" out and dropped them into some cups of regular white vinegar, some "industrial strength" white vinegar, and several different dilutions of 85% Food Grade Phosphoric Acid that I have onboard.  Phosphoric Acid is the active and main ingredient in products like Barnacle Buster/Sew Clean.  It's also an ingredient in many soft drinks like Coke. The vinegars had no effect on the calcium whatsoever.    The Phosphoric Acid dissolved the scale when diluted with water as much as 7:1, albeit slowly.  A 5:1 dissolved large chunks quickly.

Hope this helps!

--
Mark McGovern
SM #440 Cara
Belfast, ME USA


Mark McGovern
 

Nick,

The hose in the above picture lived most of it's life flushing salt water.  I converted the boat to fresh water flush in 2018 about a year after buying the boat.  It has been flushed exclusively with fresh water since that time.

--
Mark McGovern
SM #440 Cara
Belfast, ME USA


Rudolf Waldispuehl
 

Hi Dean

 

I used to use just freshwater but I found out that the tubes getting barnacles and other growth in it due to the constant flow of Saltwater from the fridge pump.

Since 2 year I buy just about 10lt of normal household (cleaning) vinegar. Very cheap about .70 cents per liter at grocery (Mercadona). It is not aggressive and helps to clean out the tubes.

 

I fill up the Aircon and Fridge lines and let it work over night. After that I flush out everything with fresh-water from the shore and let it in over winter.

There is quite a lot of lime(calc)-dirt coming out with the vinegar. Sometimes I add a bit off antifreeze which is corroding protective as Nick mentioned.

 

Best regards and good preparation

Ruedi

WASABI A54-#55

 

Von: "main@AmelYachtOwners.groups.io" <main@AmelYachtOwners.groups.io> im Auftrag von Dean Gillies <stella@...>
Antworten an: "main@AmelYachtOwners.groups.io" <main@AmelYachtOwners.groups.io>
Datum: Montag, 8. November 2021 um 15:42
An: "main@AmelYachtOwners.groups.io" <main@AmelYachtOwners.groups.io>
Betreff: [AmelYachtOwners] Descaling the Seawater Lines

 

Hi all,
I'm preparing Stella for in-water wintering in southern Spain and will be filling all seawater lines with freshwater as I've always done in the past for non-freezing winterisation.  

I'm wondering about the wisdom of treating the seawater lines with some kind of de-scaling treatment. I've previously cleaned my ONAN heat exchanger with dilute Hydrochloric Acid (Muriatic Acid) but that seems a bit over the top to flush right through the seawater systems. I know some folks like barnacle buster and such-like.  I don't have any symptoms of poor water flow anywhere, so my gut feel says "if it ain't broke ...".  Am I missing something?

Cheers
Dean
SV STELLA
A54-154
   


Dean Gillies
 

Mark,
Don't I know that job from a previous boat, so I hear you loud and clear!

Luckily Stella is all freshwater flushing.  I had occasion to be servicing the heads (joker valves and macerators) earlier this year and I had a look at the hoses. There was some build up but nothing like I have seen with salt-water systems. I gave them a ream-out regardless with some rigging wire, modified at the end to look like a "brush".  Also, they are still flexible along their length. 

I was really happy with the easy access to tanks and pipes that the Amel design affords. On other boats I've had to cut through fibreglass to get at things! 

Good to know that the phosphoric acid products work on those lumpy bits.

Cheers
Dean
SV STELLA 
A54-154


Dean Gillies
 

Hi Ruedi,
Thanks for that.  Flushing the fridge/aircon with product is much easier than running it through the motor/generator due to water flow volumes.  Do you think this is not needed so much with the engines?

Hope your travels are going well. Wasabi looks splendid.
Cheers
Dean
SV STELLA
A54-154


 

Mark,

My exact experience with white vinegar and I let the chunks soak for 6 months...still nothing.

Bill


CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar

On Mon, Nov 8, 2021 at 10:59 AM Mark McGovern <mfmcgovern@...> wrote:
Dean,
 
While I am usually an advocate of the "if it ain't broke don't fix it camp" I will advise you to preventatively address at least one of your heads if at all possible.  Either by treating it to reduce scale or by just replacing the hoses outright.  I say this because I had one head clog up within a few weeks of moving aboard full time earlier this year.  Changing out the hoses out when they are filled with shit-water is just about one of the worst jobs I have ever done on a boat.  Certainly the "shittiest."  Taking the hint, I pre-emptively replaced the hoses on the other head soon thereafter.  Here is what the cross-section of hose looked like on the head that I changed out BEFORE it stopped working:



The 38mm ID hose had a true ID of maybe 20mm.  And yes, that is a tampon shoved up inside the hose.  The hose was so stiff from all the calcification that I had to cut the hose into several sections in order to remove it.  Tampon did a great job absorbing the residual bleach water that was in the hose.

For fun, I knocked some of the "chunks" out and dropped them into some cups of regular white vinegar, some "industrial strength" white vinegar, and several different dilutions of 85% Food Grade Phosphoric Acid that I have onboard.  Phosphoric Acid is the active and main ingredient in products like Barnacle Buster/Sew Clean.  It's also an ingredient in many soft drinks like Coke. The vinegars had no effect on the calcium whatsoever.    The Phosphoric Acid dissolved the scale when diluted with water as much as 7:1, albeit slowly.  A 5:1 dissolved large chunks quickly.

Hope this helps!

--
Mark McGovern
SM #440 Cara
Belfast, ME USA


Rudolf Waldispuehl
 

Hi Dean
Thanks, all fine here... 
Engine and Gen I keep some deluted Antifreece in it after water flushing.

Maybe vinigar is also good for Engine and Gen. I never found an appropriate fluid/chemistry for it, 
and all the descaler seemed to aggressively in my mind.
Maybe I should not worry?

Can’t find barnacle booster in Europe for a reasonable price and quantity. 
I think heat-exchange service is due from time to time anyhow.;-)

Cheers 
Ruedi

Von meinem iPhone gesendet

Am 09.11.2021 um 01:08 schrieb Dean Gillies <stella@...>:

Hi Ruedi,
Thanks for that.  Flushing the fridge/aircon with product is much easier than running it through the motor/generator due to water flow volumes.  Do you think this is not needed so much with the engines?

Hope your travels are going well. Wasabi looks splendid.
Cheers
Dean
SV STELLA
A54-154


rossirossix4
 

I'm not that optimistic but I'd love to see if Salt-A-Way solution has any impact on disolving chunks.  We use a solution when we rinse generator, engine, AC, toilet feed pumps, anchor wash, etc. and sometimes flush it down the toilets.

I've posted this elsewhere, but for anyone wanting to flush with fresh water but (like most of us when not docked) AND wanting to preserve fresh water.....We keep a plastic 8" diameter plastic mixing bowl in each head sink.  We use the kind of kitchen bowl that has the urethane soft bottom.  It catches the water when we wash hands or face.  We empty it down the head after a thorough salt water flush.  The water usually has some liquid soap in it as well.  As a result the toilet hoses are filled with a fair amount (or total, depending) of fresh soapy water.  Bonus--you can do the same to prevent mouthfuls of toothbrushing rinse and--if you shave--hair, from coating the hoses to the bilge and ending up in the bilge sump. (or if you are accurate just spit it out into the toilet). There have been a number of postings wondering about bilge sump smell even though kitchen sink waste is carefully controlled--we noticed a significant decline when doing this.

Bob       KAIMI SM429