Aquahot contamination

[Cincy22EC]

I saw some old posts on this but wanted to start a new thread. ‘24 CS and I discovered my AH fluid which was originally bright and clean yellow/green when I bought the coach new last April is now mixed with brown yuck.

I’m wondering if this is possibly related to a slight loss in engine coolant where I lose enough to go just below the site glass after about 1k miles.

I have an AIR scheduled with Entegra 4/7 so we shall see what they say. Meanwhile I have the coach at Cummins to inspect for the coolant leak. They won’t touch the AH but want to make sure it’s not leaking somewhere else.

Does anyone know exactly how the engine coolant works with the AH and how it may contaminate the boiler fluid?

And no, I’ve never put anything other than green stuff in when it was pretty new to top off to the hot level.

[d23haynes57]

Originally Posted by Cincy22EC

I saw some old posts on this but wanted to start a new thread. ‘24 CS and I discovered my AH fluid which was originally bright and clean yellow/green when I bought the coach new last April is now mixed with brown yuck.

I’m wondering if this is possibly related to a slight loss in engine coolant where I lose enough to go just below the site glass after about 1k miles.

I have an AIR scheduled with Entegra 4/7 so we shall see what they say. Meanwhile I have the coach at Cummins to inspect for the coolant leak. They won’t touch the AH but want to make sure it’s not leaking somewhere else.

Does anyone know exactly how the engine coolant works with the AH and how it may contaminate the boiler fluid?

And no, I’ve never put anything other than green stuff in when it was pretty new to top off to the hot level.

Engine coolant and potable water should never mix. if it does you have a breach in one of the heat exchangers. This could be dangerous if engine coolant should ever make it the domestic supply. For a fairly new unit this breach would usually be caused by the system being operated dry and an exchanger failing from burn out or overpressure. Another failure could be the domestic water heat exchanger freezing.
Brown much could also just be organic matter growing in the coolant from when it is not in use. Go find a test lab and have a sample tested. The test will find if there is Ethylene glycol contamination.

[hogdriver]

That ain’t good. I had my 2014 Anthem AquaHot turn to coffee color in my first 12 months. I flushed it w distilled water (posted in 2015-2016)then refilled with Camco pink and it remained great for years. Yours appears contaminated with oil. The Aquahot is heated by the coolant loop. Unless your engine coolant is also bad….indicating a bad heat loop coil and serious engine problems…I don’t see how oil could get into the AquaHot fluid.

When you pull the engine dipstick while engine running do you get a forceful blast of air? Indicating a bad head gasket. I’m not sure if you can pull out the dipstick on that ISX engine when running.

You might consider ordering one of those engine oil sample kits or coolant sample kits and send to a lab for analysis before your AIR

[brobox]

I am sure you have seen this post, which was a total nightmare on the cause. .https://www.irv2.com/forums/f278/aqu...ge-270914.html

Engine coolant does not come in contact with the AH fluid, just circulate around the AH using the engine heat to transfer to the AH.

After my nightmare, paying 3rd party fluid testing, it came down to a bad batch of Century fluid. Nobody would spend the money to prove me wrong, so that was mine and the fluid engineers opinion. In the end, my fluid was sludge and no long flowing through the system

Your under warranty, Entegra will probably flush the system as they did mine. If I was out of warranty, it would be flushed and different brand used, no matter what color. To be honest, I would use Glycol non food grade as I don't drink coach water anyhow

[Cincy22EC]

Originally Posted by d23haynes57

Engine coolant and potable water should never mix. if it does you have a breach in one of the heat exchangers. This could be dangerous if engine coolant should ever make it the domestic supply. For a fairly new unit this breach would usually be caused by the system being operated dry and an exchanger failing from burn out or overpressure. Another failure could be the domestic water heat exchanger freezing.
Brown much could also just be organic matter growing in the coolant from when it is not in use. Go find a test lab and have a sample tested. The test will find if there is Ethylene glycol contamination.

The engine coolant nor the AH boiler fluid are mixing with the potable water. The water system is fine. The problem is in the AH fluid alone. And since I am seeing a slight drop in coolant level it has me thinking the heat exchanger lines from the engine coolant to the AH are leaking but I am not exactly sure how that is configured.

[Cincy22EC]

Originally Posted by brobox

I am sure you have seen this post, which was a total nightmare on the cause. .https://www.irv2.com/forums/f278/aqu...ge-270914.html



Engine coolant does not come in contact with the AH fluid, just circulate around the AH using the engine heat to transfer to the AH.


After my nightmare, paying 3rd party fluid testing, it came down to a bad batch of Century fluid. Nobody would spend the money to prove me wrong, so that was mine and the fluid engineers opinion. In the end, my fluid was sludge and no long flowing through the system


Your under warranty, Entegra will probably flush the system as they did mine. If I was out of warranty, it would be flushed and different brand used, no matter what color. To be honest, I would use Glycol non food grade as I don't drink coach water anyhow

Yep, read all of those last night. My gut tells me this has something to do with my slight coolant loss I'm seeing. I don't think its related to any other engine or oil issue. I'll know more when Cummins gets back to me on the coolant loss issue.

Just when I thought I had all of my 1st year bugs worked out! I literally had 4 straight trips and 4k miles without even getting a screw driver out.

[brobox]

Originally Posted by Cincy22EC

The engine coolant nor the AH boiler fluid are mixing with the potable water. The water system is fine. The problem is in the AH fluid alone. And since I am seeing a slight drop in coolant level it has me thinking the heat exchanger lines from the engine coolant to the AH are leaking but I am not exactly sure how that is configured.

The coolant level can drop to normal evaporation of the water from the glycol. To be sure what is going on, it might be worth getting the fluid engineers contact information from my post and had a fluid sample run before going to Entegra.
Here is the contact info. Tom Johnson, Coolant Analysis
North America: +1-877-251-8315

[Cincy22EC]

Originally Posted by brobox

The coolant level can drop to normal evaporation of the water from the glycol. To be sure what is going on, it might be worth getting the fluid engineers contact information from my post and had a fluid sample run before going to Entegra.
Here is the contact info. Tom Johnson, Coolant Analysis
North America: +1-877-251-8315

Thanks. I'm concerned about the engine coolant loss because it seems excessive. About 8 ounces after 1000 miles each of the last few times out. How often are you having to top off above the site glass?

[DoggieDaddy]

In my opinion the AH fluid turning brown is a natural thing with the heating of the fluid, evaporation and etc. The fluid in our coach turned brown during the first year and stayed that way for the eight years we owned the coach. I also think the sludge problem that Chuck experienced had to do with the coach setting unused for periods of time which allowed the solids to settle making a sludge. Since we "full timed" and the AH was running daily the fluid was in constant circulation keeping the solids suspended. I don't think the OP has an AH issue to worry about, but the radiator coolant is another thing.

Good Luck.

[hogdriver]

Read the postings some more . If the engine coolant is dropping somewhat, it could be a problem with the AquaHot engine heat exchanger inside the AH unit. I’m guessing the engine coolant is at a higher pressure than the AquaHot loop. If the engine coolant mixes with that boiler fluid it could cause the AH fluid to turn colors. Chuck and I both had problems in 2015 with our boiler fluids turning colors. When we had chemical tests done AquAhot and Century boiler fluids were real fast to say mixing anything other than water with that boiler fluid will cause it to discolor (i.e. any other brand of coolant)

[Cincy22EC]

Originally Posted by DoggieDaddy

In my opinion the AH fluid turning brown is a natural thing with the heating of the fluid, evaporation and etc. The fluid in our coach turned brown during the first year and stayed that way for the eight years we owned the coach. I also think the sludge problem that Chuck experienced had to do with the coach setting unused for periods of time which allowed the solids to settle making a sludge. Since we "full timed" and the AH was running daily the fluid was in constant circulation keeping the solids suspended. I don't think the OP has an AH issue to worry about, but the radiator coolant is another thing.

Good Luck.

My fluid was nice and clean green/yellow until this past fall. Bought the coach new in April 2024 then noticed a little discoloration in the expansion bottle. Used the AH pretty regularly this winter with a bit more change. Then it got really nasty looking this past month. So, I don't think its a "normal" discoloration. Plus it looks like 2 different fluids. It actually doesn't seem to mix well and one is heavier and lying on the bottom of the other. On the bottom of the expansion tank it was nearly pure deep brown until I sucked enough out to get the green stuff.

[Cincy22EC]

This was the clear tube after I began to siphon out from the bottom of the tank.

[shepardmike]

This is what mine looked like after I first started using my AH. The dark stuff on the sides was floating around. I asked around and everyone said this is normal . and yours looks twice as bad. I would get it checked.

[Cincy22EC]

Mine looked like that briefly then got completely discolored to the point where I can barely tell what the level of the fluid is. Waiting to hear back from Entegra as to what they think is going on. They’ll have it on 4/7 to do an AIR and I’ll see what they say.