Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 09, 2025 ...

Another Aqua Hot problem

September 09, 2018, 10:46:23 pm

Hello all, I'm getting ready to head east from Washington towards Yellowstone via Hells Canyon, Idaho and Jackson, leaving in two weeks. Last April I took the coach to a certified aqua hot service, they replaced the ignition and did some other work and said it runs great.  I have had no reason to turn it on until today and as usual it's not working. At least the diesel part is not working. When switched to electric 115 volts it works fine just takes longer. When I use the diesel switch the green light comes on for 10-15 seconds and then goes off, there's also a little compressor (?) that comes on, not sure what that is about.

Anyhow any information would be helpful before I try to get it back to the service tech. Just don't have a lot of time left, as work still gets in the way.

Thanks Eric
P.S. Checked the fuses there fine and the three big relays looked okay also.

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Re: Another Aqua Hot problem

Reply #1 – September 09, 2018, 11:45:01 pm

That noise is the blower. Many things can cause the symptoms you are having. Flame sensor, coil, fuel pump, control box etc. Maybe Rudy can give you a hand at trouble shooting. There is a post with the AH service manual somewhere on the Forum.

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Re: Another Aqua Hot problem

Reply #2 – September 10, 2018, 07:39:27 am

Aquahot Diesel Burner Troubleshooting

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Re: Another Aqua Hot problem

Reply #3 – September 10, 2018, 08:32:40 am

You could try unplugging the control box and using Deoxit to clean the pins where they plug in.  If you don't have Deoxit or some other contact cleaner then just unplugging & plugging in a few times cleans the contacts.

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Re: Another Aqua Hot problem

Reply #4 – September 10, 2018, 08:43:56 am

Morning Eric,

Sorry to share but letting the burner sit for weeks on end with out running it through a diesel heating cycle has allowed the fuel on the new nozzle to congeal.  The fix is a new nozzle.

Once this is done, run the burner through one heating cycle once per month wheather you need to or not, period.  The new nozzle will last 2 maybe 3 years if given this periodic use.

To put it another way, the shelf life of a new uninstalled nozzle is indefinite.  The shelf life of an installed nozzle starts downhill at 30 days of no use.

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Re: Another Aqua Hot problem

Reply #5 – September 10, 2018, 09:17:20 am

Thanks Everyone, thanks Rudy, so its like ethanol gas in a Honda generator. Another question, the noise I hear after I turn the unit on that sounds like a small compressor (thanks Craneman, its not a blower) or a vacuum pump continues to run even after I shut the "diesel switch" off.  What is its purpose? It's mounted to the basement ceiling behind the inverter.
Thanks againn
Eric
PS. Is changing a nozzle difficult for the average do-it-yourselfer (you knew that question was coming)

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Re: Another Aqua Hot problem

Reply #6 – September 10, 2018, 09:20:03 am

Eric,

Call me and I can give a quick education on what is supposed to happen and what to do and look for.

Rudy  7 one 3  8 one 8  3234

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Re: Another Aqua Hot problem

Reply #7 – September 10, 2018, 09:28:00 am

It isn't really difficult, but it isn't like taking apart a toaster.  Here is an excellent video (the nozzle comes in at about the 10 min. mark):  https://www.youtube.com/watch?v=9p5T6ixogEk

I was given this exact schooling by a pro last year and it cost me over $1100 when I had a problem.  Video is a lot cheaper.

Also, it is much easier to start up the unit AND generator monthly!

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Re: Another Aqua Hot problem

Reply #8 – September 11, 2018, 08:40:08 am

Update, talked with Rudy he gave me an run down of the system, thanks Rudy. Ordered another nozzle but wont be here till Thursday so I soaked the old one in carb cleaner, sprayed it with brake fluid and goof off, rinsed and repeated several times. It now works as it should but will replace with the new one when it arrives.

Thanks again everyone
Eric

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