Jump to content

Aqua-Hot Model 100-04 Emergency Repair


Dr4Film

Recommended Posts

Folks, I just wanted to share what I did to get my Aqua-Hot working once again after waking up and finding no hot water yesterday.

Sometime ago I discovered that I had a small pin-hole in the filler neck of the Aqua-Hot boiler. In order to continue using the Aqua-Hot, I lowered the level in the tank by one gallon and have been using it that way since I purchased the coach in 2022.

Well, the reason I had no hot water yesterday was the Low Level Coolant Fault LED Light was on. So I added two quarts to the tank and the fault light did not reset. Now, I decided to check the integrity of the Coolant Level Float Valve by jumping terminals #15 & #16. When I did that the fault light went out. So my float valve has failed.

I then decided it was a good time to add the two bottles of Irontite to the boiler tank and fill the system up with boiler fluid. Fired the diesel up and wrapped paper towel around the filler neck to capture any fluid that could come out of the pin-hole leak. Well there was NADA, nothing. Another win for Irontite!

Plus the fluid is now entering the over-flow bottle like it should. Once the diesel burner shut off I filled the bottle up to the HOT level on the over-flow tank with normal green coolant as that's all I had in the coach. After all, once I installed the Irontite to the system the special boiler fluid is no longer needed.

Now I can watch the over-flow tank to ensure that the boiler tank does not get too low on fluid.

For the cost of the boiler fluid float valve plus the time and labor to install it, I will go without it. In my opinion that is just another failure point which generally happens at the worst possible moment when you need the Aqua-Hot. The older Aqua-Hot models never had a Float Valve plus I always watch my over-flow tank levels to make sure the tank is full of boiler fluid all the time.

  • Like 2
Link to comment
Share on other sites

Good job.  If the leak comes back you may try one of the replacement filler necks offered online.  They just clamp on. 

As long as you have the over temp protection circuits, I'm not sure the float valve is necessary.

Link to comment
Share on other sites

I'm at about 1 1/2 years with Irontite sealing my boiler tank!

Recently replaced my boiler fluid / water, and added just a half bottle of Irontite. Don't know whether it needed it or not, but I didn't want to risk losing brand new, expensive boiler fluid.

Link to comment
Share on other sites

Posted (edited)
1 hour ago, timaz996 said:

I'm glad my old Aqua Hot uses regular antifreeze.😁

First time mine has been changed since the coach was built, so, not exactly breaking the bank on it 😁!

I purchased 4gal of -100, thinking I'd have enough for the change, and extra to cover future evaporation.

Turns out, the 450D holds so little, 2gal of -100 is enough to cover the change as well as top-ups!

I mixed it to give me -17C protection.

Edited by 96 EVO
Link to comment
Share on other sites

I don't plan on going back to the special boiler fluid now that I have added the Irontite and the green ethylene glycol boiler fluid to the tank.

My engine uses the green coolant and now the Aqua-Hot does also. Frankly I like it that way as I only have to carry one fluid for both purposes.

Link to comment
Share on other sites

1 hour ago, Dr4Film said:

I don't plan on going back to the special boiler fluid now that I have added the Irontite and the green ethylene glycol boiler fluid to the tank.

My engine uses the green coolant and now the Aqua-Hot does also. Frankly I like it that way as I only have to carry one fluid for both purposes.

Well, if your hot water smells 'funky' while your showering, don't drink any 😮!

Link to comment
Share on other sites

We have never drank any water from the coach be it from our fresh water tank or shore water hookups. We use strictly bottled water or bulk Primo water refill bottles. We even do that when we are home in Flagler Beach.

Link to comment
Share on other sites

2 hours ago, Dr4Film said:

I don't plan on going back to the special boiler fluid now that I have added the Irontite and the green ethylene glycol boiler fluid to the tank.

My engine uses the green coolant and now the Aqua-Hot does also. Frankly I like it that way as I only have to carry one fluid for both purposes.

Richard,

I don't know exactly what AH unit you have.  BUT...for the RECORD and from the STAFF. We have to post notes or qualify when certain things are stated here that are in conflict with the Vendor's instructions.

ONLY USE THE PROPER COOLANT IN AN AQUAHOT.  Read the manual for which Coolant is to be used.  From page 1 of my manual...which is a AHE-450-DE/DM

This Aqua-Hot product utilizes a propylene glycol
based antifreeze and water heating solution. This
Propylene glycol based solution is a boiler type
antifreeze that is “Generally Recognized as Safe”
(GRAS) by the FDA. For additional information
regarding this “GRAS” antifreeze product, reference the
Appendices, contact the Aqua-Hot Heating Systems
Technical Support Department at 1-800-685-4298, or
visit the Web site www.aqua-hot.com.

There was an issue and a redesign some years ago. Aquahot changed coolants from the "Ethylene Glycol" to the current non toxic coolant.  I do NOT know the year, but thought it was prior to 2006.

These NEWER MODELS are not supposed to use ANTIFREEZE or Ethylene Glycol as there is a concern about drinking contaminated water. Ethylene Glycol is considered to be toxic. Therefore, any member that reads this should be aware and only follow the Vendor's recommendations for their unit.

I do NOT know the year that the conversion took place.  BUT I was caravanning with several individuals with 2008 Navigators.  One had low coolant.  The owner filled the overflow with regular antifreeze.  The MH then had to be flushed and  such to eliminate any contamination.  I was walking by and noticed the jug of PRESTONE.  They were not aware of it. 

My AH is a 2009 model...  Theirs was also supposed to use the Special NON Toxic boiler coolant.

 

Link to comment
Share on other sites

Just a word of caution.  There are two different aquahot systems.  The older ones have external heating to coils OUTSIDE the tank.  Newer systems like in my 08 Dynasty have internal higher efficiency heating coils INSIDE the tank.  These latter systems require propylene glycol.  Earlier systems can use toxic ethylene glycol and stop leak additives if needed.

Richard, if your heat exchanger loop is internal to the tank - no way would I add any additive not approved as a safe in a domestic hot water system.

  • Like 2
Link to comment
Share on other sites

Posted (edited)
1 hour ago, Frank McElroy said:

Just a word of caution.  There are two different aquahot systems.  The older ones have external heating to coils OUTSIDE the tank.  Newer systems like in my 08 Dynasty have internal higher efficiency heating coils INSIDE the tank.  These latter systems require propylene glycol.  Earlier systems can use toxic ethylene glycol and stop leak additives if needed.

Richard, if your heat exchanger loop is internal to the tank - no way would I add any additive not approved as a safe in a domestic hot water system.

I'm guessing, and Richard will correct me if I'm wrong, he has already added a toxic substance to the boiler fluid. So it doesn't really matter anymore!

Something I never really thought of when I first added a bottle of Irontite to seal my leaking boiler tank.

I would say a chance of a leak in the domestic water coil in the boiler tank would be slim, but not 0!

I'm a bigger risk taker than some, and less than others!

One last point, with your domestic water usually being under pressure, and your boiler basically not, if you were unfortunate enough to spring a leak in your domestic water coil, 'inside' the boiler tank, your likely going to know about it by your AH expansion tank overflowing. Since I've had a boiler tank leak, I monitor the level in the expansion tank often!

Edited by 96 EVO
Link to comment
Share on other sites

Posted (edited)

I’m my case the domestic water loop had a leak. The issue with contamination can occur due to the fact that the glycol circuit does become pressurized at operating temp and the domestic side is not always pressurized. It your water pump is not on or hooked up to “city” water and have a leak you risk the fluid containing your fresh water. I choose to fix things properly and never have put anything in a system that it wasn’t designed for it in any vehicle or system.

Edited by Chargerman
Link to comment
Share on other sites

@Tom Cherry @Frank McElroy

Thank you moderators for posting a disclaimer which I should have done in my original post for those members and the thousands of "guests" we have visiting this site daily.

You are correct, the three older versions of the Aqua-Hot, models 100-01, 100-02 & the 432/12 all came with external fresh water loops around the OUTSIDE of the boiler tank. That allowed the use of the green ethylene glycol boiler coolant in those tanks. Well, except for the Aqua-Hot model 431/12 that is installed in my previous Windsor now owned by @Lenny D who recently had a new boiler tank installed which now has the fresh water loop INSIDE the boiler tank.

The newer model Aqua-Hots, 100-03, 100-04, 450 series and the new 600 series all have internal fresh water loops INSIDE the boiler tank. This requires the use of a special boiler coolant that is not lethal to humans.

In my specific situation, I chose to add a toxic additive to the boiler coolant tank to seal the pin hole leak instead of spending thousands of dollars on a permanent fix. I will NEVER spend that much money on ANY Aqua-Hot unit ever again. If or when needed the Aqua-Hot will be removed and an Espar unit will be installed.

So, with that said, I will monitor the level in the Aqua-Hot overflow tank daily to make sure that the high level is not rising which will indicate that the fresh water loop has developed a leak. We will also monitor the water used in the coach to make sure it doesn't start turning brown.

Plus I always have the water pump turned on whether we are hooked to shore water or not. If that starts to cycle unnecessarily, that may also be an indication.

Closely monitoring the overflow tank and the water pump will give me an early warning to a leak if that should happen.

However, I am banking on the chances of having a leak in the fresh water coils that are INSIDE the tank are less than those that are located OUTSIDE the tank. I have read about more owners with the older Aqua-Hot units having to replace or rebuild due to fresh water leaks in their AH units including myself with a 4 year old Aqua-Hot in my previous 02 Windsor back in 2005. That one lasted for 19 years.

Link to comment
Share on other sites

On 5/22/2024 at 7:21 AM, Dr4Film said:

Folks, I just wanted to share what I did to get my Aqua-Hot working once again after waking up and finding no hot water yesterday.

Sometime ago I discovered that I had a small pin-hole in the filler neck of the Aqua-Hot boiler. In order to continue using the Aqua-Hot, I lowered the level in the tank by one gallon and have been using it that way since I purchased the coach in 2022.

Well, the reason I had no hot water yesterday was the Low Level Coolant Fault LED Light was on. So I added two quarts to the tank and the fault light did not reset. Now, I decided to check the integrity of the Coolant Level Float Valve by jumping terminals #15 & #16. When I did that the fault light went out. So my float valve has failed.

I then decided it was a good time to add the two bottles of Irontite to the boiler tank and fill the system up with boiler fluid. Fired the diesel up and wrapped paper towel around the filler neck to capture any fluid that could come out of the pin-hole leak. Well there was NADA, nothing. Another win for Irontite!

Plus the fluid is now entering the over-flow bottle like it should. Once the diesel burner shut off I filled the bottle up to the HOT level on the over-flow tank with normal green coolant as that's all I had in the coach. After all, once I installed the Irontite to the system the special boiler fluid is no longer needed.

Now I can watch the over-flow tank to ensure that the boiler tank does not get too low on fluid.

For the cost of the boiler fluid float valve plus the time and labor to install it, I will go without it. In my opinion that is just another failure point which generally happens at the worst possible moment when you need the Aqua-Hot. The older Aqua-Hot models never had a Float Valve plus I always watch my over-flow tank levels to make sure the tank is full of boiler fluid all the time.

Richard which Irontite product did you use? I'm thinking of having a bottle on hand for just in case.

Link to comment
Share on other sites

I was first introduced to the Irontite product back in 2015 when my radiator developed a leak in the lower portion of the fins while on the Cassier Highway in Northern British Columbia. Had to be towed over 200 miles to Terrance BC to a truck shop where they suggested I try the Irontite. I agreed. They put in two bottles and 12 gallons of new coolant and said to drive it about 50 miles to circulate the Irontite really well. I never lost another drop of coolant during that 50 miles.

I then drove another 5000+ miles while never losing another drop of coolant all the way to Gadsden AL where they installed a new radiator into my Windsor.

By the way, the shop was able to reuse all of the new coolant that had been installed in BC. All that was needed was to replace the coolant filter with a new one.

Two years later, a service tech noticed that the new radiator was oozing at the top someplace so I tossed in another two bottles of Irontite and that stopped the oozing.

I am a huge proponent of this product.

Link to comment
Share on other sites

On 5/22/2024 at 8:18 PM, Chargerman said:

My 06 has an internal loop. I replaced my tank last year due to an internal leak. 

@Chargerman Would you be so kind and share how you discovered the leak in your internal fresh water loop? What were the symptoms that led you to the leak? Both myself and most likely @96 EVO would like to know.

Link to comment
Share on other sites

My issue was that my overflow tank kept rising/ overflowing. I then removed the fitting for the fresh water loop and made a setup so I could pressure test the loop. Took about a second to hear air bubbling inside the tank. 

Link to comment
Share on other sites

Posted (edited)

I dove in as far as one can by removing the unit and sending the tank to John Carillo to use as a core and he sent me a refurbished tank. No way to get to that internal coil without cutting open the tank and rewelding it when done

Edited by Chargerman
  • Like 1
Link to comment
Share on other sites

1 minute ago, Dr4Film said:

If mine fails I won't be replacing it with another one that will fail.

The Espar unit comes with a Hot Water on Demand so there is no internal fresh water loop to fail.

Interesting!

I never looked that far into them.

20 minutes ago, Chargerman said:

I dove in as far as one can by removing the unit and sending the tank to John Carillo to use as a core and he sent me a refurbished tank. No way to get to that internal coil without cutting open the tank and rewelding it when done

When my tank started leaking, I 'tried' contacting Carillo, but got no reply!

That's when I started looking at alternative fixes.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...