2003 Imperial AquaHot - No domestic hot water

[snowman]

Agua hot heater 2003 HR imperial read operators manual not real clear is there a thermostat that I can turn up to get better heat, unit is new to us first time out cause I tried the shower and Luke warm not sure on kitchen sink for temp 

[Jonbrooks]

I have a mixing valve that controls how hot the water gets. I replaced the valve when rebuilding my aqua hot. It sits below the diesel heater so access is by removing the covers. 

[Dr4Film]

You need to read up on your Aqua-Hot Owner's Manual as to its operation, etc. If you don't have one, below is a link to the website where you can download one after you find your exact model number which is on a label inside the Aqua-Hot Stainless-Steel cover. It will most likely be one of the discontinued models.

Aqua-Hot Manuals (aquahot.com)

In the manual, it will explain the operation of the Aqua-Hot System which you need to fully understand as they are somewhat complex systems.

Plus, they require routine maintenance.

Basically, there can be a multitude of reasons why you have a lack of really hot water or heat.

The manual also includes troubleshooting steps which may help you in determining exactly what your problem may be.

If the system is TOO complex, then I would strongly suggest having a certified Aqua-Hot service technician look into the problem.

[Flyinhy]

I just finished rebuilding my unit. Follow docs advise and download the manual and understand how the unit works before attemping to repair. 

[WayneC]

Familiar site Charles,I ended up replacing the burn chamber as well,may be worth taking it out and having a good look before you put everything back together,I cleaned all the soot out after I took the chamber out with shop vac.

Wayne 

1999 Signature ceaser 

[Tom Cherry]

1 hour ago, Dr4Film said:

You need to read up on your Aqua-Hot Owner's Manual as to its operation, etc. If you don't have one, below is a link to the website where you can download one after you find your exact model number which is on a label inside the Aqua-Hot Stainless-Steel cover. It will most likely be one of the discontinued models.

Aqua-Hot Manuals (aquahot.com)

In the manual, it will explain the operation of the Aqua-Hot System which you need to fully understand as they are somewhat complex systems.

Plus, they require routine maintenance.

Basically, there can be a multitude of reasons why you have a lack of really hot water or heat.

The manual also includes troubleshooting steps which may help you in determining exactly what your problem may be.

If the system is TOO complex, then I would strongly suggest having a certified Aqua-Hot service technician look into the problem.

GREAT POST.  Two QUICK THINGS....without getting into all the "WOW....what did I DO?".

First, on the Aqua Hot control box (in a bay outside), look at IT. If you see any "LIGHTS", such as Low Coolant, then that may be the issue. You MIGHT have the 12 VDC Low light on. Use a straightened paper clip and push the reset button in the hole. That resets it. Make sure the coolant level in the reservoir is correct. WARNING....you need to talk to AH as to WHAT type of fluid and the mix (Distilled water to concentrate Fluid) is.  SOME of the units in your age used plain old Car (Green) Antifreeze.  Later on, they changed to a special "Potable Boiler Mix" antifreeze. Word on the street is that is hard to find now.  Camco used to sell it and CW had it.  DO NOT use any coolant to replenish it without knowing, exactly from AquaHot what to put in...

Second, you MIGHT need to turn on the Diesel Burner switch.  Sometimes when you use a lot of hot water, the Electric Button will not provide enough power.  This assumes that you know that to have hot water, either the Electric or the Diesel (and you can run BOTH at once) needs to be ON.  Otherwise, you only get ambient temperature water. Sorry if this seems talking down, but it HAS happened to a new owner.

Past THAT....read the manual, which you have started to. There is NO thermostat to adjust. You MIGHT have, Probably?) TWO individual Thermostats. They may be the same temperature of maybe 10 - 20 degrees difference.  If you have ONE, it controls BOTH the electric heater and the Diesel burner. They are in the 180 dF range...so the water inside the AquaHot boiler is really HOT. You also need to know that when you drive, assuming all is working well, your engine coolant heats the water. Thus when you set up, you will have residual hot water...but it cools. 

Hope this helps...Download the AH manual and read.  Read the BASICS FIRST...how it works. Understand that there are several pumps inside the unit....maybe 5 on your system.  One is the RECIRCULATING Pump. That comes one everytime the boiler is heated by the Diesel or Electric unit.  Then you have pumps for each heating zone.  Maybe 3...or maybe 2.  You also have a pump for using the AquaHot to reverse heat the Engine coolant. These pumps, especially the age of yours, if left sitting for a while will have the "Check Valve" stick.  The SIMPLE FIX....use a large handled screwdriver and tap on the housing.  Don't try to use the same force as driving a nail. I good RAP, not a blow from a 20 pound sledge....is all it takes to get them working. 

You can set the HVAC Thermostat to FURNACE.  Then turn up all the zones to 80 or so.  You need the DIESEL burner switch ON. Then, after say 5 - 10 minutes, you will hear the individual register fans come one and get hot air.  The diesel burner should fire immediately when you turn up the Thermostats... You MUST feel the heat coming out of the exhaust pipe and smell the burning diesel.  

The MOST COMMON Failure is an OLD nozzle. As Richard said, have the AH serviced. There is a nozzle that has a serrated metallic "filter" inside it. There is also external filter. The burner pack needs to be adjusted also. I had to have mine recently serviced as it sat for almost a year...and eventually, even with good Diesel fuel, the nozzle gets a bit clogged and you just replace it....NO CLEANING OUT...unless you soaked it in a high solvent liquid...but the "Standard" AH job replaces the filter and the nozzle and also checks the pumps for working and totally checks and adjusts the system. It is just something that needs doing every 2 or so years...3 pushes it...

Good Luck.

[Flyinhy]

I did, I couldn't believe how much soot was inside the burn chamber. I probably removed 2lbs of soot. I also replaced the electrical element and 2 thermostats along with the nozzle and rubber grommets. The electrical element was a tough. Over the years it had bent upwards and seperated but after a few choice words and a little blood, it finally came out.  She runs like a top now. 

[WayneC]

7 minutes ago, Flyinhy said:

I did, I couldn't believe how much soot was inside the burn chamber. I probably removed 2lbs of soot. I also replaced the electrical element and 2 thermostats along with the nozzle and rubber grommets. The electrical element was a tough. Over the years it had bent upwards and seperated but after a few choice words and a little blood, it finally came out.  She runs like a top now. 

Nice 

[snowman]

8 hours ago, Flyinhy said:

I just finished rebuilding my unit. Follow docs advise and download the manual and understand how the unit works before attemping to repair. 

 

Just now, snowman said:

 

This is what mine looks like 1st question,  I need to hire a child to get in there 2nd question I have a serial number of 02-1009 and found that in my paper work binder but no operation manual where do I look for a model number someone posted to look in manual or download 1 but no clue what model to download 

[Dr4Film]

Remove the Stainless Steel cover to access the label with the model number on it.

[Flyinhy]

Looks like the same as mine ....model 100-2s. Google Aquahot 100-2s manual  and a pdf file will be one of your first results. And yes, you have to be quite flexable to get in there, do you have access to the side of the unit from the compartment next to it? The first thing you need to check is the water level. The rad cap is in the center on the top of the unit and even if your resevoir is full, your tank may not be.....

[sg47619]

Welcome to my world, mines a 2001 Dynasty Jack 38 and the guy I bought it from wasn’t forthright in all that was going on with it. This site is a life saver. 

[Grampy OG]

I got lucky when I had the same symptoms and all I needed was a new mixing valve. Easy to get to and not very expensive. 

Several of you mentioned cleaning the burn chamber. Is that something that can be done in place or does the AH need to be removed from the coach? 

Mine is old circa, '03', and I believe it is model AH-100-2S or close to that. 

Thanks gang,

Ken

 

[Guest Ray Davis]

1 hour ago, Grampy OG said:

Several of you mentioned cleaning the burn chamber. Is that something that can be done in place or does the AH need to be removed from the coach? 

 Most of us have never removed an Aqua-hot that would be a deal breaker for me.   No it's not necessary in order to clean the soot.  Actually you were there when you   had the burner out to work on the tempering valve.   With the burner out pull the flue tube ( may not be the proper name ) clean it and the combustion chamber.             I use a variety of brushes and my shop vac.   It is a messy job, wear gloves and have a shop vac handy.  Soot is nasty stuff

16 hours ago, sg47619 said:

Welcome to my world, mines a 2001 Dynasty Jack 38 and the guy I bought it from wasn’t forthright in all that was going on with it. This site is a life saver. 

If a seller was completely forthright about one of these rigs no one would buy it.  We would have to pay them.  LOL  Besides who could make a list that long.

Seriously,  we should all remember it's Caveat emptor,  let the buyer beware.

[vito.a]

The most common problem with new Aqua Hot owners is they turn the Aqua Hot electric switch on for 30 min and do not have hot water.  

The electric element in these early units is quite small and does not produce hot water in a short period.  

You should turn on the Diesel burner and listen to it closely.  Become familiar with the sounds of when it first spools up, then lights the burner, after 20 min shuts off the fuel, then cools down and finally shuts off.  Also watch the exhaust pipe for black smoke.  

These early model AHE-100 systems do not have the light board like the newer systems.  

Another trick.  You can fill your fresh water tank the day prior and it will slowly warm up in the basement.  Then the next day your hot water will be warmer because the incoming water from the tank is warmer.  

[wamcneil]

On 8/7/2022 at 5:01 PM, snowman said:

 

This is what mine looks like 1st question,  I need to hire a child to get in there 2nd question I have a serial number of 02-1009 and found that in my paper work binder but no operation manual where do I look for a model number someone posted to look in manual or download 1 but no clue what model to download 

You've probably got an access door of some kind between the storage bay next to the right-side of the aquahot. So climb into that adjacent storage bay and have a look.

Cheers,

Walter

[snowman]

When we got home and got to looking into the other owners manual and it stated in there that the electric side of the water heater only works on 50 amp only and  well we were plugged into 30 amp only this weekend 8-13  we plugged into 50 amp and it worked awesome 

[Dr4Film]

1 hour ago, snowman said:

When we got home and got to looking into the other owners manual and it stated in there that the electric side of the water heater only works on 50 amp only and  well we were plugged into 30 amp only this weekend 8-13  we plugged into 50 amp and it worked awesome 

The Aqua-Hot Electric Assist should work while hooked to any shore VAC power, 50, 30, 20 or 15 amp, NOT just 50-amp. Plus, it should also work when your generator is running. The electric heating element is a 120 VAC 1650 Watt element.

When you are on any shore power that is LESS then 50 amps it is always a good idea to monitor your wattage usage and if needed, turn off the Aqua-Hot Electric Assist to allow the amperage to be used for other devices and only use the Diesel Burner of the Aqua-Hot as that is your primary heating source.

Or, if your coach is equipped with an Intellitec EMS System, it may automatically shed the AH Electric Assist (aka Water Heater) when on 30 amp or less shore power since the Water Heater is the very first device to shed. Example below.