AHE-600-D03 Use and Care Guide

Safety Instructions

Read all instructions before operating the Aqua-Hot unit. AquaHot Heating Systems is not liable for damage resulting from failing to follow instructions contained in this, and any other Aqua-Hot documentation relevant to this unit.

• Read this manual before using the Aqua-Hot System to reduce the risk of injury to persons or damage to the equipment.
• The product identity label contains specifications of the unit, to what standards it has been tested, and important safety notices.
• The Aqua-Hot tank and heating loop operate at 0.0 PSI (zero pressure system). Air pressure to the tank must not exceed 20 PSI. Exceeding this rating will cause internal damage to the Aqua-Hot.
• Have your dealer show you the location and operation of all switch functions and valve settings.
• Propylene glycol “Generally Recognized As Safe” by the FDA, must be utilized for the antifreeze and water heating solution.
• Interior heat can still be used once the water heating system has been drained and winterized.
• Use propylene glycol “Generally Recognized As Safe” RV & Marine antifreeze specifically for “winterizing” application only.

• At maximum operating temperature, the coolant will be very hot and scalding. Hot vapor or coolant may cause in serious burns or injury. Be aware of hot surfaces.
• The hot water temperature is set at the mixing valve to 120°F at the factory.
• DO winterize the heating system when freezing temperatures are expected to avoid serious damage to the hot water system.
• DO NOT operate the burner or electric element without antifreeze and water heating solution in the boiler tank to avoid damage to the heater.
• Aqua-Hot’s exhaust is HOT. DO NOT park is dry areas when operating to avoid fi re and injury to persons.
• Before cleaning or servicing, disconnect all power supplies.
• The heater must be switched OFF when refueling.
• DO NOT operate the Aqua-Hot’s diesel burner inside an enclosed building.

System Overview

The Aqua-Hot 600D is a Hydronic (water-based) Heating System, a tank-less hot water system, and a diesel engine preheating system.

The heating system provides moist, quiet, comfortable, interior heat with up to 5 separate, thermostatically-controlled temperature zones, and prevents tank and line freezing in the bays.

The tank-less hot water system produces 90 gallons per hour of continuous, on-demand hot water.

The diesel engine preheating system circulates the engine’s antifreeze solution through an internal heating loop in the AquaHot and pumps it back through the engine, raising the engine’s temperature from 30°F to 90°F in about 1 hour.

The same heating loop that preheats the diesel engine allows the Aqua-Hot system to take surplus heat generated by the motor home’s diesel engine while running, and use it to heat the Aqua-Hot system.

This TribridHot™ designated system uses one or a combination of heat sources to heat FDA-Approved Generally Recognized As Safe (“GRAS”) Propylene Glycol-based antifreeze solution in the Aqua-Hot’s boiler tank.

The 600D has multiple heating sources: the motor home’s engine’s surplus heat (while driving), two 120V AC - 2000W Electric Elements (when plugged into shore power), and a 12V DC powered diesel burner (when dry camping). These heat sources can be used separately or simultaneously.

System Features

The Aqua-Hot Heating System is a Low Emissions Hydronic Heating System (heating with hot water) that significantly improves your level of comfort, decreases harmful emissions released into the atmosphere, and adds thousands of dollars in valve to your RV.

The Aqua-Hot Heating System is a 4-in-1 system

1. Interior Heating System: Provides quiet, comfortable interior heat with independent temperature zones that provide cabin-wide, even temperatures.
2. Bay Heating System: keeps pipes and tanks from freezing in the bay storage area.
3. Tank-less Hot Water System: provides a steady fl ow of continuous hot water.
4. Engine Preheating System: reduces engine wear caused by cold-starting by preheating the engine from 30°F to 90°F in one hour.

The Aqua-Hot is powered by TribridHot™ technology and uses one or a combination of the following heat sources:

1. 120V AC & 240V AC Electric Elements: When plugged into shore power, the elements lets you use the power you are already paying for to provide heat and light duty hot water.
2. Diesel Burner: This is the Aqua-Hot’s most powerful heat source and provides all of the heating and hot water needs in cold temperatures or dry camping.
3. The Vehicle’s Engine: When driving or idling, the engine’s surplus heat is transferred to the Aqua-Hot, providing interior heat and limited hot water without burning any other fuel.

Component Callouts

Control Overview

Coach Control Panel Screen:

Newer Aqua-Hot units that come equipped with the Reporter may have a coach touch-screen display instead of the interior switch panel. Please confirm with your coach dealer or vehicle manufacturer the location and functionality of your interior control screen.

Switches:

The Aqua-Hot heating system is controlled by three switches, the burner switch, the electric element switch, and the electric high/low switch. This style of Aqua-Hot is equipped with an Engine Preheat element as well. When one or both the burner or electric element switches are in the ON position, it will supply the necessary heat to the boiler tank. Keep in mind that the Aqua-Hot must be at operating temperature for the heating zones and hot water to function properly. Please contact the specific motor home dealer for the exact location of switch operations. See below for an example of the interior switch panel.

Thermostats:

The interior room thermostat can be set at the desired temperature; therefore, whenever the interior of the room “calls for heat”, the Aqua-Hot’s circulation pump and interior heat exchanger fans will be activated. The fresh water thermostat controls the bay heating area and should NOT be set below 40°F, to prevent freezing of the domestic water storage system. Please contact the specific coach dealer for exact location of thermostat controls.

Heating Operation:

The heating features are powered by a 12V DC diesel burner and two AC electric elements. These heating elements maintain the temperature of the Aqua-Hot’s antifreeze and water heating solution to provide hot water and interior heat.

• Burner - The diesel burner is the Aqua-Hot’s primary and most powerful heat source, and provides all of the heating and hot water needs when cold temperatures exist, and/ or when there is a high demand for hot water. It can be activated by turning the burner switch in the ON position or by tapping the burner to ON on the coach display screen.
• Engine Preheat - In order to use the Engine Preheat element on the Aqua-Hot system, both the diesel-burner AND the engine preheat must be turned ON. Allow the engine preheat element to function for one hour before starting the vehicle’s engine.
• Electric - The electric element is the Aqua-Hot’s secondary heat source and can be used when plugged into shore power. The electric element provides heat when moderate temperatures exist (50°F or higher), and/or when there is a low demand for hot water. It can be activated by turning the electric switch in the ON position, or by tapping the electric to ON on the coach display screen.
  • Low Switch - Moving the High/Low switch to the “LOW” position will energize one of the two AC elements inside the Aqua-Hot. On the “LOW” setting, allow 1-2 hours for the Aqua-Hot to reach operating temperature.
  • High Switch - Moving the High/Low switch to the “HIGH” position will energize both AC elements within the Aqua-Hot, providing adequate heat for light-duty heating and hot water needs. Allow 30 minutes to 1 hour for the Aqua-Hot to heat to operating temperature.

Controlling Heat Levels:

The interior room thermostat can be adjusted at the desired temperature and will automatically be activated to maintain the temperature of the interior. Keep in mind that the diesel and/ or electric element must be in the ON position for the heat to operate.

Control/Balancing Heating Zones:

Set the interior room thermostat for each independent heating zone at the desired temperature. This feature allows you to customize various temperatures on each heating zone throughout your coach.

Domestic Hot Water System

General Information:

The Aqua-Hot system is known as an on-demand hot water heating system because hot water is not stored within the coach. Instead, when the burner and/or electric element(s) are ON and the Aqua-Hot is at operating temperature, the water is automatically heated as it is being used. Therefore, simply open a hot water faucet once system is up to operating temperature, and a continuous supply of hot water will be present within a few seconds.

To operate the Aqua-Hot hot water system, you will need to locate the interior switch panel or coach control panel located inside your coach. If you are unable to locate the interior panel, contact your dealer to guide you in the location and operation of all switch operations. Once you have located the interior control panel, turn the burner to ON. This action will activate the dieselburner. Allow 10-20 minutes for the Aqua-Hot system to reach operating temperature. Please note that the diesel-burner is the primary heat source for heating the interior and hot water.

To operate the electric heating element, turn the electric ON. This action will activate the AC electric heating element. Allow 1-2 hours for the Aqua-Hot system to reach operating temperature. Be sure to activate the electric element switch for maximum water capacity.

Some coaches may be equipped with touch-screen panels in lieu of the Aqua-Hot three-switch panel. If you are unsure if your coach is equipped with touch screen controls, please contact your coach manufacturer.

Tempering Valve

The Tempering Valve for the Aqua-Hot mixes the heated domestic water from the boiler tank with cold domestic water at the present ratio to reduce the risk of scalding. This valve is located in the back of the Aqua-Hot unit as shown in Figure 17.

The pink paint witness mark verifies that the Aqua-Hot is set at the correct factory setting and did not get tampered with during shipping or installation. Verify that the Tempering Valve is set at the proper temperature by using a digital thermometer at one of the hot water faucets. The water temperature should range between 115°F to 123°F. If the correct temperature cannot be set, please contact AquaHot Heating Systems Technical Support Department at 1-800- 685-4298 for additional assistance or visit our web site at www. aquahot.com.

Operational Flow Chart

Maintenance Schedule

Overview:

The Aqua-Hot system requires minimal maintenance if monthly, annual, and proper winterization procedures are followed accurately. It is extremely important to follow the instructions below precisely and carefully to receive the best results and promote the longevity of your Aqua-Hot. Monthly maintenance to the Aqua-Hot requires a visual check of the antifreeze and water solution to make sure it’s at the correct operating level. Annual maintenance to the Aqua-Hot requires a replacement of two parts on the diesel-burner, the fuel nozzle and fuel filter. Winterization of an Aqua-Hot system prepares a coach for storage during the winter months to prevent freezing pipes and other critical damage.

Monthly:

It is extremely important to check the Aqua-Hot’s antifreeze and water heating solution to ensure it is at the proper level for operation. This task can be done by visibly checking the coolant level in the Aqua-Hot’s expansion tank. At maximum operating temperature, the antifreeze and water heating solution should be at the level marked “HOT” on the expansion tank. The coolant level should be checked ONLY when the Aqua-Hot is at maximum operating temperature. Therefore, this procedure should be done immediately after the diesel-burner cycles OFF. When the antifreeze and water heating solution needs replenishing, remove the expansion tank’s cap and fill to the “HOT” level mark. When refilling, open the air release valve located on the expansion tank connection to release air pockets. Be sure the valve is closed when finished by hand tightening.

Annual:

In order to keep the Aqua-Hot running at its full potential, it’s highly recommended to have the diesel-burner tuned up annually. This tune up consists of a new fuel nozzle (Part Number: WPX-886-41A) and fuel filter (Part Number: FLE-120- 100). To ensure maximum diesel-burner performance, always use the recommended fuel nozzle and fuel filter when replacing these parts. Reference the Aqua-Hot’s Service and Parts Manual for spare parts information and detailed replacement attachments.

Overheat Protection

Every Aqua-Hot is equipped with at least two overheat protection devices. These are commonly known as the highlimit thermostats. These thermostats operate by maintaining a circuit while the unit is below 218° F (103° C). In the event of an overheat condition, the high limit thermostats will cut the operating signal to the diesel burner and/or the electric element. When this signal is interrupted, the electric element and diesel burner will immediately disengage. Contact Aqua-Hot Heating Systems LLC for assistance in locating a qualified person to service this heater.

Winterization

Winterizing the Aqua-Hot

The Aqua-Hot’s domestic water heating system must be completely drained of domestic water at any time the heater is stored where freezing temperatures may be experienced. Please follow these instructions when winterizing the AquaHot domestic water heating system. Reference Figure 10 for a system overview.

1. Completely drain the fresh water storage tank.
2. Disconnect the domestic water demand pump suction line from the fresh water storage tank.
3. Attach an adequate piece of hose onto the suction side of the domestic water demand pump.
4. Place the opposite end of the hose into an adequate supply of non-toxic RV winterization antifreeze (FDA certified as “GRAS” Generally Recognized As Safe must be used) and allow the fluid to pump through.
5. Open and close all interior and exterior water faucets one at a time, until ONLY pure RV antifreeze is present. Perform this procedure for both cold and hot water faucets.
6. Remove the hose and reconnect the domestic water demand pump’s suction line to the fresh water storage tank.

De-Winterization

To de-winterize the Aqua-Hot system, completely fi ll the fresh water storage tank. Open and close the interior and exterior faucets, one at a time, until only clear water is present.

Disinfecting the Domestic Water System

The Aqua-Hot Heating systems contain copper tubing and are not compatible to prolonged exposure to sodium hypochlorite (bleach or liquid bleach). Using products containing bleach, including water refreshers, may cause corrosion of the domestic water lines, resulting in a catastrophic failure of the Aqua-Hot system by creating leaks that cannot be repaired. This damage is not covered by the Aqua-Hot warranty.

If disinfecting the hot water system, be sure to follow NFPA 1192 Standard on Recreational Vehicles “Instructions for Disinfection of Potable Water Systems” or any other applicable local standards for Potable Water Systems.

Antifreeze Types

The following information addresses the necessary usage of a propylene glycol based “boiler” type antifreeze in the Aqua-Hot. Propylene glycol is a safer alternative to the more toxic ethylene glycol antifreeze; however, as mandated by IAPMO (International Association of Plumbing and Mechanical Officials), only propylene glycol based “boiler” type antifreezes deemed “Generally Recognized As Safe” (GRAS) by the FDA should be utilized.

Due to the significant impact various types of antifreeze can have on a hydronic heating system, including the level of safety provided, it has been recognized that there is a need to provide an explanation regarding two additional prominent types of antifreeze/coolant available. The following information should be utilized as an educational means of ensuring that the proper type of propylene glycol based antifreeze is selected.

RV & Marine Antifreeze

These types of propylene glycol based antifreeze products are formulated specifically for “winterizing” applications only. Although RV & Marine antifreeze is often “Generally Recognized As Safe” by the FDA, it should never be used in the AquaHot’s Hydronic Heating System. This type of antifreeze is not formulated to transfer heat, which is essential to the heating system’s functionality and does not contain rust inhibitors. Please note, however, that RV & Marine antifreeze can be utilized to winterize the Aqua-Hot’s Domestic Hot Water Heating Systems.

Automotive Antifreeze/Coolant

These types of propylene glycol based antifreeze products are formulated specifically to protect automotive engines against corrosion, freezing temperatures, and overheating. They also have excellent heat transfer and thermal conductivity characteristics. Although these types of antifreeze products are considered less toxic and safer than ethylene glycol for people, pets, and the environment, they are not “Generally Recognized As Safe” (GRAS) rated by the FDA. Therefore, they must be marked with a “harmful if swallowed” warning. This additional warning is required because these types of antifreeze products contain high levels of chemical rust inhibitors. Due to their potentially hazardous properties, they should never be used in the Aqua-Hot’s Hydronic Heating System.

Antifreeze Mixture Quality Recommendations

In order to ensure maximum performance and longevity of an Aqua-Hot heating system’s boiler tank and associated components, it has been determined that there is a need to use distilled, deionized, or soft water in combination with concentrated propylene glycol for the Aqua-Hot’s antifreeze and water heating solution.

Please note that this is only necessary when mixing concentrated propylene glycol antifreeze with water; suppliers of premixed antifreeze are responsible for the use of highquality (distilled, deionized, or soft) water when preparing their antifreeze for sale.

Hard water possesses a high-level of calcium and magnesium ions, which deplete the propylene glycol antifreeze’s corrosion inhibitors. This, in turn, causes the antifreeze and water heating solution to begin turning acidic, which can corrode the AquaHot’s boiler tank and associated components prematurely. Therefore, concentrated propylene glycol should be diluted with distilled, deionized, or soft water which is 80ppm or less in total hardness. The local water agency should have up-to-date water quality reports, which should indicate if the local tap water is within this guideline.

General Troubleshooting

Your new Aqua-Hot 600D contains the Aqua-Hot Reporter, a replacement for our previous electronic controllers.

Should the Aqua-Hot Hydronic Heating System fail to operate, complete the following checks:

1. Verify that the Aqua-Hot’s access cover is securely installed. The Aqua-Hot Hydronic Heating System will not operate if the access cover is not fully installed.
2. Ensure that the vehicle’s fuel tank contains a sufficient level of fuel. The Aqua-Hot system will not operate if the fuel level is at or below ¼ tank.
3. Ensure that the Aqua-Hot’s boiler tank has an adequate supply of antifreeze and water heating solution by checking the level at the Expansion Tank. If the level is low, reference the Care & Maintenance section of this guide for refilling instructions.
4. Check the Aqua-Hot Reporter faults screen for any faults, and if any, record all fault conditions which have occurred.

If the Aqua-Hot Heating System’s failure to operate is not resolved with the aforementioned checks, please contact the Aqua-Hot Heating Systems Technical Support Department at +1 (800) 685-4298 for additional assistance or visit our website at www.aquahot.com. If the Aqua-Hot’s diesel burner switch “light” (on the interior switch panel) does not illuminate and the diesel burner is not functioning, locate the Reporter and check the following items.

Reporter Diagnosis:

1. Check the Reporter fault screen for any fault conditions associated with this unit. Record these conditions.
2. Check for loose wire connections on the Reporter by removing the four bolts/screws securing the housing to its mounting position. It may be necessary to check with your coach manufacturer to determine the best way to remove the Reporter. Do NOT remove the circuit board from the housing.
3. Remove the Reporter and ensure that all connections are secured, and that the wires are in good condition Reference Figure 11.
4. Ensure the vehicle’s fuel tank has a sufficient level of fuel.
5. If the Aqua-Hot still fails to operate, please contact the Aqua-Hot Heating Systems Technical Support Department at 1-800-685-4298 or visit our web site at www.aquahot. com.

The Aqua-Hot Reporter contains both a fault page, and a fault log. The fault page contains information on faults that have occurred since the last time the Reporter was reset or powercycled. The fault log cannot be cleared and it can contain up to four historic fault conditions, not necessarily related to a present issue. The Reporter will display the following fault conditions accompanied by the component causing the fault (pump, fan, burner, etc).

Testing Functionality

Reset Feature

The RESET button shown above on the Reporter fault screen can be used to reset the Reporter after a component has been changed or modified. Some components will require a full power-cycle in order to fully reset the Aqua-Hot system.

Over-Current

An over-current fault condition occurs when too much current is drawn by a component (output channel), usually a fan or pump. When an over-current condition occurs, the Reporter will deactivate the output component as a safety measure to prevent damage. This fault can only be cleared once the Reporter has been reset. Please note, that if the responsible component is not repaired or replaced, it can continually cause over-current fault conditions, thereby impacting the functionality of the Aqua-Hot unit.

Over-Temperature (Reporter 2.0)

The Over-Temperature fault condition occurs when the tank temperature sensor indicates that the unit has overheated. An overheat is realized when the antifreeze and water heating solution within the Aqua-Hot exceeds 210°F.

Low-Voltage

The Reporter is designed to operate between 11V Direct Current (DC) and 16V DC. If the Reporter detects that it is receiving less than 11.8V DC, it will display a low-voltage fault. If the Reporter drops below 11.2V DC for more than 30 seconds, a safety mechanism will activate, shutting down the Aqua-Hot.

Low-Level Cut Off

Aqua-Hot units require a minimum amount of antifreeze in order to function correctly. Keep in mind that the exact fluid volume may differ depending on the layout of your coach. If the heater drops below the minimum fill level as indicated on the expansion bottle, the Reporter will shut down all fans, pumps, and heat sources until the unit has been refilled and the Reporter has been reset.

Ignition Failure

Ignition failure fault conditions will occur if the burner inside the heater fails to ignite. This is all the fault condition will display. Precise diagnosis herein will require in-depth troubleshooting.

Testing Functionality

The Reporter has been designed to include a host of test features allowing for quicker diagnosis and repair of components. Using the “PREVIOUS” and “NEXT” buttons on the test screen, it is possible to cycle between the burner and electrical subsystems, zone fans, and pumps. The tests are sorted into different screens; TESTING—PUMPS, TESTING—HEAT, TESTING—FANS. Only one screen of tests may be used at any one time. Starting a pump test, then switching to the TESTING—FANS screen will deactivate the pump test. In addition, the Reporter will “timeout” after five minutes of non-interaction, returning to the home screen. This will disengage any tests currently in progress.

Pump and Zone Fans

Pumps and zone fans are activated individually, and remain so until the Reporter times out, or the test is manually ended.

Heating Subsystems

The Reporter will allow the electric and burner sub-systems to be activated and run for a maximum of fi ve minutes to verify functionality of those systems. Please note that if used improperly, this testing tool could cause damage to your AquaHot unit and the heating subsystem test is NOT a replacement for standard unit operation. If you have any questions, please don’t hesitate to contact the Aqua-Hot technical support department at 1-800-685-4298.

Heartbeat Function

Aqua-Hot Reporter units with firmware 1v5 and later and all Reporter 2.0 units are equipped with a “heartbeat” function which establishes a signal between the RVC system and the Reporter. The Reporter will be constantly awaiting a signal from the RVC network indicating to the Reporter that it is to continue normal operation. Loss of 6 consecutive signals from the RVC network will trigger the Reporter to deactivate the Aqua-Hot. This serves as a safety feature to ensure that the Aqua-Hot does not continue to operate if the coach loses power. Once power is restored to the coach and the Reporter unit, “BATTERY DISCONNECT SWITCH OFF” will be displayed in the fault log, indicating that the Reporter has lost connectivity with the RVC network.

Manual Mode

The 2.0 Reporters with CFG 1.9 and greater come with a manual mode in case the general coach RVC network fails. It will allow for limited operation while the larger network/module problem is addressed. To determine the version of Reporter, the Reporter 2.0 modules are shipped with version decals affixed to the back of the circuit board, OR shown on the home screen - “FW: 2.0”. This mode can accessed under the test page of the Aqua-Hot Reporter (see below).

Once the test page is open, select the MANUAL MODE and select “NEXT”. Manual mode will continue to run for up to 3 days without any user intervention. Pressing the reset button at any time while enabled will reset the timer, and run for an additional 3 days.

All heating zones are linked together and can be run at 25%, 50%, 75%, and 100% (as shown below). The burner and electric can be enabled or disabled. For all levels, there is a 10 minute duty cycle period that will allow Cozy fans to be on for the specified percentage of 10 minutes. Example, 25% would be on for 2.5 minutes, and then off for 7.5 minutes. It always starts with the on-cycle, then shuts off for the remainder of the 10 minute period.

If the system power is cycled, the manual mode will be disabled and must be manually reactivated. Leaving the manual mode page will also disable manual mode and restore normal operation. Leaving manual mode should be done once the system failure has been resolved and normal operation can resume.