Aqua Hot question

[Lenny D]

Hello, I’m new and I have concerns with my Aqua Hot.

My AH will not stay on. I have a toggle switch that shows a blue light when AH is on. I usually leave it on all the time. What’s been happening lately is the light will go on when I turn on the switch, I can hear the AH start to run but it will shut off after less than 60 seconds. My fuel gauge is at 3/4. That is above the usual level of 1/4 tank when the AH will cut off. I am getting hot water on demand but it seems like its running out too quickly. I am also running heat quite a bit over the last week as I am in the northeast (Jersey) and we’ve been having lower than normal temperatures. Is it coincidence that with the heat running my hot water is not lasting as long? 
 

Thank you in advance.

LD

 

 

[DavidL]

Sounds like service is needed.

Did you check the antifreeze level?

Did you check the "idiot" lights on the aquahot panel?

Sounds like the system is going into a fault mode, shutting down, resetting and the cycle starts over.

You may be running out of heat because the system is shutting itself down.

When was the last time service was done?  ie: Nozzle and filter and electrode replacement?  If that has been more than a year ago, I would check coolant and then do that service (without knowing what fault is being set).

 

[Tom Cherry]

3 hours ago, DavidL said:

Sounds like service is needed.

Did you check the antifreeze level?

Did you check the "idiot" lights on the aquahot panel?

Sounds like the system is going into a fault mode, shutting down, resetting and the cycle starts over.

You may be running out of heat because the system is shutting itself down.

When was the last time service was done?  ie: Nozzle and filter and electrode replacement?  If that has been more than a year ago, I would check coolant and then do that service (without knowing what fault is being set).

 

Go to the AH website and find an authorized dealer or repair shop.  Many listed.  These folks have actually attended an AH training session.

The AH will plug up sitting.  The nozzle builds up gunk.  Typically you might get by with a once per 3 year cleaning and tuning.  That will include the pumps, check valves, circulation system, heat exchangers, nozzle/boiler clearance adjustment and new fuel filter,  

Mine was done in 2017.  It worked ok through 2020, but failed in 2021.  Had it serviced.  Nothing wrong,,,,just needed a new nozzle and cleaning and tuning.  Great now.  Sometimes the igniter goes….but mine works fine.  The light going off or into fault is typical.  AH tech support will not tell you anything until it has been serviced or tell you, if you have the skill set, to do that.

as a word of advice.  Run your Genny and HP regularly to keep the reversing valves working and the Genny “dried out”.

[SteveB]

Hello Lenny,

You can download the repair/maintenance shop manual for your unit from AquaHot.  There are also many videos on YouTube that will help.

If you are skilled I would start with replacing the fuel filter. Run it until the burner has clean fuel, then replace the nozzle. I am assuming your fuel is good.  In most cases I would say the nozzle is clogging.

I had a problem similar to yours.  I would reset it and it would do the same thing again. Eventually it stopped coming on all together.  I would turn it on and tap the back of the blower unit.  This would start it up and it would run for a while and then shut down.  I thought that there may be a flat spot on the blower motor as when I tapped it, the motor would start.  So I gathered all the parts  and I rebuilt it.  I have had experience maintaining Becket and Ingorsoll Rand oil fired burners.  When I did the tear down, I found out that one of the bearings had seized and I assumed that was the culprit.  But I was already there, I had all the parts, and the unit is from 2001 so I replaced blower motor, bearings, washers, ignition wires, fuel nozzle, gears, grommets, gaskets -everything I could replace.

Runs perfect like it did before, only now everything is brand new. 

 

[DavidL]

BTW, the bearings are "skate board wheel" bearings...MUCH less expensive....

[RWHenhouse]

Sounds like your diesel burner isn't igniting.  After the flame sensor fails to detect flame the control box closes the fuel valve, runs the blower for a minute or so to clear diesel vapors and shuts down.  Toggling switch repeats the attempt.  Repeated attempts will result in a lot of raw unburnt fuel in the burner.  It's easy to tell if this is happening, turn it on and then see if the exhaust ever gets warm.  The hot water/heat you do get is being generated by the electric element which I assume is switched on.  Replacing the fuel nozzle and filter usually corrects the problem.  

[96 EVO]

16 hours ago, DavidL said:

BTW, the bearings are "skate board wheel" bearings...MUCH less expensive....

Really!

Are skateboard wheel bearings all the same size?

Gee! The grandson is gona be pi**ed if my AH ever breaks down 😄!!

Edited October 21, 2022 by 96 EVO

[Lenny D]

Interesting discoveries. Without getting into detail I recently had the coach at a body shop to have some work done. It was there for 7 weeks without any type of trickle charge and nobody's starting the motor or the generator. The chassis battery was cooked as they had to jump it several times. I replaced the battery. They also drained the house batteries. With that said, I noticed that my voltage for the house batteries was bouncy between 11.8 and 12 volts only. After doing some youtubing I found out the Aqua Hot will not ignite on low voltage. I started the motor and the generator and the Aqua Hot started right up with no problem. I'm going to do a load test on the house batteries I may have to replace those as well.

[DavidL]

1 hour ago, 96 EVO said:

Really!

Are skateboard wheel bearings all the same size?

Gee! The grandson is gona be pi**ed if my AH ever breaks down 😄!!

I can't remember if I double checked when I rebuilt mine of the bearings in the furnace and the bearings in a skateboard..  I seem to remember that I pre-ordered the bearings from the HydroHot repair place and when I ultimately took mine apart, realized they were skateboard wheel bearing size.  I had paid MUCH more for the bearings from HydroHot supplier.

I worked in a sporting good store MANY years ago.  At that time the sealed bearings were all the same size from wheel to wheel.  Roller skate wheels too.

But, I am sure there are different sizes today too.

 

It's a really common bearing size.  a RV water pump and a hot tub circulation pump I rebuilt also used same bearing...I keep a sleeve of them handy.

 

Quick Google  https://www.amazon.com/Dsenfurn-Bearings-Double-Rubber-Sealed/dp/B09JKF83V8/ref=sr_1_1_sspa?crid=27NJSQNV890OV&keywords=skateboard+bearing&qid=1666373412&qu=eyJxc2MiOiI1LjA1IiwicXNhIjoiNC40NSIsInFzcCI6IjQuMTgifQ%3D%3D&sprefix=skateboard+bearing%2Caps%2C126&sr=8-1-spons&psc=1

Edited October 21, 2022 by DavidL

[Ivan K]

Exactly what I carry with me too. 608-2RS.  Very common, couple of fuel pumps in cars in my shop use the same ones. I did not have to replace them in AH yet.

[96 EVO]

Ever hear your motor slow down several RPM's during the purge cycle, after a burn?

[Lenny D]

96 EVO ... Yes. When I turn the toggle on for the AQ a blue light comes on, the motor starts, then after a few seconds the RPM's drop and the light dims a tad .. When its working its at this point the burner fires up. As ti is now, when the light dims and the RPMs drop the burner does not ignite and the light goes out. The more I try and the more it doesn't ignite the longer the white smoke from the burn off lasts when it does start. 

On 10/21/2022 at 11:30 AM, RWHenhouse said:

Sounds like your diesel burner isn't igniting.  After the flame sensor fails to detect flame the control box closes the fuel valve, runs the blower for a minute or so to clear diesel vapors and shuts down.  Toggling switch repeats the attempt.  Repeated attempts will result in a lot of raw unburnt fuel in the burner.  It's easy to tell if this is happening, turn it on and then see if the exhaust ever gets warm.  The hot water/heat you do get is being generated by the electric element which I assume is switched on.  Replacing the fuel nozzle and filter usually corrects the problem.  

 

That is exactly what it sounds like to me as well. For a moment I thought I wasn't getting enough voltage to the igniter but that turned out to be a wrong assessment. I'm trying to schedule a service appointment but up here in the Northeast finding an AQ service person int so easy. . . Thank you.

[Lenny D]

On 10/20/2022 at 12:03 PM, Tom Cherry said:

Go to the AH website and find an authorized dealer or repair shop.  Many listed.  These folks have actually attended an AH training session.

The AH will plug up sitting.  The nozzle builds up gunk.  Typically you might get by with a once per 3 year cleaning and tuning.  That will include the pumps, check valves, circulation system, heat exchangers, nozzle/boiler clearance adjustment and new fuel filter,  

Mine was done in 2017.  It worked ok through 2020, but failed in 2021.  Had it serviced.  Nothing wrong,,,,just needed a new nozzle and cleaning and tuning.  Great now.  Sometimes the igniter goes….but mine works fine.  The light going off or into fault is typical.  AH tech support will not tell you anything until it has been serviced or tell you, if you have the skill set, to do that.

as a word of advice.  Run your Genny and HP regularly to keep the reversing valves working and the Genny “dried out”.

 

This sounds like a high possibility .. The coach sat for 7 weeks at a body shop without being started and they also allowed the batteries to drain. I haven't fueled up for over 2 months .. We're currently still parked at home with plans on heading out the end of Nov. My last fill up I did add fuel treatment. I'm thinking its clogged nozzle ..Although when it does start it blows the white burn off ... This AQ does not have the LED panel. Also, it's a PIA to get to. I have to pull a storage slide out on the drivers side and crawl in on the passenger side and there are access doors .. No matter, I wouldn't try to do it. .. Thanks

 

[Viper04]

I believe all Aquahot owners have a ❤️ Love/Hate relationship with there units. Love them when they are working correctly and really hate them when they are not. 
 

after patching mine for many years and accumulating enough spare parts and costs to assist Space X on the Mars mission, I just bit the bullet. 
 

Called hydro hot and got a complete new burner assembly. Every thing but the combustion chamber. Also converted to the new round gauge Dometic thermostat 

display. Got a year warranty (WOO HOO-Lol!). Expensive for sure but, the last burner assy lasted 20 years. (With the last five years having some crazy faults time and again. 
 

pros- I been in Kansas in 5-10 degree weather and windchills  Below 0. I was the only unit in the RV park NOT TO FREEZE UP AND Maintained 70 degrees. Weather lasted a long 6 days with plenty of ice and snow. If they are right, propane just cannot do what a Aquahot does. If maintained.. usually just a filter and orfice they are good to go. Suggest being careful on using injection cleaners with a old filter tends to break loose the stuff the filter catches and then your a hater once again. 
 

unfortunally there are a many untrained "mobile Auqahot " service techs that might not be straight up guys or gals. Find a good one and stick with them. 
The forum here probably has as much experience (and shouldered the expense too much) as most techs out there. 
I learned the most from a fellow Beaver owner and also safely saved 8 grand several years ago when I was told by a tech my unit was "just toooo old to mess with" had a bad leak on my heater coil. My Beaver buddy showed me how to find the leak with spray foam and use a few sharks bite copper fittings and you guessed it

 

BETTER THAN NEW and Viper04 was a lot wiser using Home Depot instead of burning 8 grand. RV families are a good bunch and with a little learning you can keep your new Aquahot in your checking account or many other RV issues for that matter. 
 

Go Monacoers!

[Guest Ray Davis]

2 hours ago, Viper04 said:

My Beaver buddy showed me how to find the leak with spray foam and use a few sharks bite copper fittings and you guessed it

Viper, if you would elaborate about how you used the foam and fittings, I would sure appreciate it.  Thanks

 

Lenny D, as stated the burner needs a tune up now and then.  Your symptom is sometimes caused by the little flame sensor that Rusty mentioned above.  Often it is just dirty, so it has trouble seeing a flame and simply needs to be cleaned. 

I have worked on my burner so many times I think I can remove mine blind folded. LOL   The burner is pretty robust just be careful reinstalling, the ears can break off if it's cocked and or over tightened. I use my shop vac and a metal brush to remove soot from the combustion chamber, wear gloves, it's messy. The most expense I've had was an ignition coil approx $450 and a control box, I can't recall but I think about another 400/500

Good luck & keep us posted.

Edited October 25, 2022 by Ray Davis

[96 EVO]

2 hours ago, Viper04 said:

I believe all Aquahot owners have a ❤️ Love/Hate relationship with there units. Love them when they are working correctly and really hate them when they are not. 
 

 

Your probably right, and I'm certainly not a hater of AH systems, done all my own maintenance, and never had a lick of trouble with mine!

What I do believe, is the newer 450D model AH's, with the tiny 5gal boiler tank, isn't big enough for a 43' coach!

 

The burner starts with a roar that could wake the dead, and due to the small fluid tank, needs to starts way too frequently!

As far as the electric side, the single 1450W element is a joke as far as coach heating goes! Maybe fine if your in a climate over 60deg.

Both electric element and diesel burner sharing the same set of low / high thermostats, is just stupid! If you have a shore power hookup, but it's too cold for the electric element to keep you comfortable, so the diesel needs to fire, you're just wasting electricity leaving it turned on!

[96 EVO]

If Monaco wasn't so worried about pinching pennies, and making profits, they should have been installing 600D's in all of their coaches 40' and longer!

[Lenny D]

As it is now I’m having a AQ tech come and do a full maintenance on it .. It’s been almost a year since it was last serviced. That’s being scheduled for next week 10/21 .. We shall see…. I will update once that’s been done. 
A big thank you for all the experienced advice. 
 

LD.

[96 EVO]

2 minutes ago, Lenny D said:

As it is now I’m having a AQ tech come and do a full maintenance on it .. It’s been almost a year since it was last serviced. That’s being scheduled for next week 10/21 .. We shall see…. I will update once that’s been done. 
A big thank you for all the experienced advice. 
 

LD.

Wish you luck!

After reading hundreds of threads on AH's, it seems you can get a good one, or a bad one!