Aqua-Hot 450-DE Series Service Manual
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Aqua-Hot 450-DE Series Service Manual

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AHE-450-DE4
SERVICE MANUAL
© 2012 Aqua-Hot Heating Systems Inc.

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Summary of Contents for Aqua-Hot 450-DE Series

  • Page 1 AHE-450-DE4 SERVICE MANUAL © 2012 Aqua-Hot Heating Systems Inc.
  • Page 2 — Page 2 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 3: Table Of Contents

    Table of Contents Section 1: Introduction to the Aqua-Hot 450-DE4 Introduction ....................... ..Page 6-7 Danger, Warning, Caution, and Note Box Definitions ............Page 6 Section 2: Aqua-Hot Hydronic Heating System Overview Technical Information ......................Page 8 I.D. Label Sample ......................Page 9 Component Overview ....................Page 9-11...
  • Page 4 Fuel Nozzle ......................Page 66-67 Fuel Solenoid ....................... Page 68 Fuel Pump ......................Page 69-71 Bearings ......................... Page 72-74 Ignition Coil ......................Page 75-76 Controller ........................ Page 77-78 — Page 4 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 5: March 2012 Aqua-Hot ® 450-De4 Hydronic Heating System Service Manual—Rev. E

    If the Aqua-Hot is Black Smoking ................. Page 79 If the Aqua-Hot is Blue/White Smoking ................ Page 80 If one of the Aqua-Hot’s Heating Zones will not get hot ..........Page 81 If there is a lack of domestic continuous hot water ............Page 82 If there is antifreeze leaking ...................

  • Page 6: Section 1: Introduction To The Aqua-Hot 450-De4 Introduction

    In order for the diesel-burner to ing, independent interior zone heating, and engine preheat- be considered as a heating source by the Aqua-Hot, it must ing. Be sure to reference Figures 3 through 5 for a com- have an adequate fuel supply, receive power from the elec- plete component overview.

  • Page 7: Introduction

    Until the thermo- stat signals that heat is no longer required, the Aqua-Hot will continue to send the heated antifreeze and water solution through the loop, which returns the cooled solution to the —...

  • Page 8: Section 2: Aqua-Hot Hydronic Heating System Overview Technical Information

    450-DE4 O ECTION VERVIEW Figure 1 Aqua-Hot 450-DE Technical Specifications Diesel-Burner, Heat Input (Firing Rate) ..............................56,000 BTU/hr Diesel-Burner, Fuel Consumption (Continuous Operation) ........................0.40 gal/hr Heater, Voltage/Maximum Power Consumption ........................12 Volt-DC/60 watts Electric Heating Element specifications ..........................120 Volt-AC/1650 watts Zone Heat Circulation Pump specifications ........................

  • Page 9: Label Sample

    1 Outlet Port Wiring Port Diesel Fuel Lines Terminal Block Diesel Burner Access Panel Interlock Switch Zone 1 Zone 2 Circulation Circulation Pump Pump — Page 9 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 10 2: A 450-DE O ECTION VERVIEW Figure 4 — Page 10 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 11 AC Wiring Cable Clamp Heating Zone Outlet Ports Heating Zone Inlet Ports I.D. Label Location Diesel Fuel Inlet/Outlet Ports Air-Release Valve Expansion Tank Connection — Page 11 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 12: Aqua-Hot Operational Flow-Chart

    2: A 450-DE4 O ECTION VERVIEW — Page 12 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 13: Antifreeze & Water Heating Solution

    Aqua-Hot Heating of chemical inhibitors. Due to their potentially hazardous Systems Inc. recommends CAMCO’s Boiler Antifreeze properties, they should never be used in the Aqua-Hot’s -100°. Hydronic Heating System. Antifreeze Types:...

  • Page 14: Antifreeze & Water Heating Solution

    Boiling Point: The Aqua-Hot utilizes the antifreeze and water heating solu- tion as a transportation means for the heat produced from the internal processes. The antifreeze absorbs the heat created until its boiling point is reached;...

  • Page 15: Diesel-Burner Switch

    The interior switch panel is used to control the two potential Electric Element Switch: heating sources for the Aqua-Hot’s boiler tank, as well as to control the engine preheat feature. When a switch is activat- When the motor home is plugged into an AC power source ed, the indicator light on the switch will illuminate.

  • Page 16: Pin Label

    NTERIOR WITCH ANEL ANUFACTURED UP TO UGUST For Heaters Manufactured Before January 2011 Figure 7 For Heaters Manufactured Between January 2011 thru August 2011 — Page 16 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 17 09/01/2011 ECTION NTERIOR WITCH ANEL ANUFACTURED FTER Aqua-Hot 450D Interior Switch Panel Rear View Diesel Burner Engine Preheat Electric Element Switch Switch Switch Switch Electronic Controller Switch Electronic Controller Pin# 2 To “Preheat-O” Pin# 2 To “Diesel-I” Pin# 4 To “Preheat-I”...

  • Page 18: Section 4: Exhaust System Requirements Exhaust System Requirements

    XHAUST YSTEM EQUIREMENTS  Because the Aqua-Hot’s exhaust is hot and must be kept The exhaust must be able to freely exit away from the away from any heat-sensitive material, the exhaust system vehicle without any obstructions. should be checked to ensure that it continues to meet the following requirements: ...

  • Page 19: Interlock Switch

    Remove the defective interlock switch from the Aqua- Hot. The interlock switch is a safety device designed to ensure that the Aqua-Hot’s access cover is securely installed before Install the replacement interlock switch onto the Aqua- allowing the diesel-burner to operate.

  • Page 20: Fluid Level Sensor

    COULD CAUSE SERIOUS DAMAGE OR PERSONAL INJURY Troubleshooting: Ensure that the Aqua-Hot has been completely shut Verify that the Aqua-Hot’s boiler tank is full of the anti- down and that all power sources have been disconnect- freeze and water heating solution.

  • Page 21: Control Thermostat

    B. Disconnect the control thermostat’s wires from their perature and when it requires heat. The Aqua-Hot is consid- connections, and, using an ohmmeter, check for ered to be at operating temperature between 158°F and continuity.
  • Page 22 If the C1 (Orange - #22) wire does not have 12VDC Re- Screw the replacement control thermostat into the port fer to the Webasto Diesel Burner Controller Trouble- on the Aqua-Hot’s boiler tank and tighten securely with shooting, in section 10. a 7/8 socket.

  • Page 23: High Limit Thermostat

    215°F. Should this temperature be reached, the Ensure that the Aqua-Hot has been completely shut down high-limit thermostat blocks the current to the element, and that all power supplies have been disconnected.

  • Page 24: High Limit Thermostats

    Ensure that the Aqua-Hot has been completely shut NOTE: Bypassing the high-limit thermostats is for testing down and that all power sources have been disconnect- only and must not be used for the Aqua-Hot’s nor- mal functioning. Remove the two wires from the defective high-limit Disconnect the DC high-limit thermostats’...

  • Page 25: Low-Temperature Cutoff Thermostat

    Troubleshooting: B. Inspect the wiring to ensure that the Aqua-Hot is wired properly and that the low-temperature cutoff Determine if the conditions are right for the “Low thermostat has not been bypassed via jumper wires.

  • Page 26: Check Valves

    5: A ECTION OMPONENTS Figure 14 Ensure that the Aqua-Hot has been completely shut down and that all power sources have been disconnect- Locate the low-temperature cutoff thermostat on the Low Temperature cold domestic water inlet pipe at the back of the Aqua- Cut-Off Thermostat Hot.
  • Page 27 Remove the hose from the defective check valve. 10. Slide the hose back onto the replacement pump and set the constant tension clamp back into place. 11. Refill the Aqua-Hot’s boiler tank with the antifreeze and water heating solution. Figure 15 Zone Check Valve —...

  • Page 28: Tempering Valve

    Remove the pressure relief valve assembly from the tempering valve assembly as the tempering valve cannot The tempering valve for the Aqua-Hot mixes the heated do- be removed from the Aqua-Hot with the pressure relief mestic water from the boiler tank with cold domestic water at valve still attached.

  • Page 29: Circulation Pumps 1

    The circulation pumps first draw the heated antifreeze and the electronic controller for illumination. water heating solution from the Aqua-Hot’s boiler tank, then propel it through the Hydronic heating system’s interior heat If the “Heating Zone Status” indicator light does not plumbing.
  • Page 30 Replacement Procedure: A450-100277 TO A450-110278 wire harness on the heater by uniting the red quick- disconnect terminals. 12. Refill the Aqua-Hot’s boiler tank with the antifreeze and AILURE TO DISCONNECT ALL POWER SUPPLIES AND water heating solution. TO ALLOW THE HEATER TO COOL BEFORE SERVICING COULD CAUSE SERIOUS DAMAGE OR PERSONAL INJURY 13.
  • Page 31 “Red Locking” tab on the harness plug, and separating the Harness Plug from the defective pump. 10. Refill the Aqua-Hot’s boiler tank with the antifreeze and water heating solution. Using constant tension pliers, loosen and slide back the constant tension clamps securing the hoses to the pump.

  • Page 32: Stir Pump

    The stir pump circulates the antifreeze and water heating tions in this section to replace the stir pump. solution within the Aqua-Hot’s boiler tank in order to ensure even-heating of the solution. To accomplish this, the stir If the “Pump #3” indicator light remains red when...
  • Page 33 Disconnect the defective stir pump’s wires by Pulling out on the “Red Locking” tab on the harness plug, and 10. Refill the Aqua-Hot’s boiler tank with the antifreeze and separating the Harness Plug from the defective pump. water heating solution.

  • Page 34: Engine Preheat Pump

    12 Volt-DC source to verify If the Engine preheat pump indicator light does not illu- that the pump is defective. minate, complete the following: — Page 34 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 35 CAUSE SERIOUS DAMAGE OR PERSONAL INJURY of channel lock pliers, to secure the pump. Ensure that the Aqua-Hot has been completely shut down Reconnect the harness plug into the replacement pump. and that all power sources have been disconnected. Also,...

  • Page 36: Engine Preheat Pump

    5: A ECTION OMPONENTS Figure 19 Engine Preheat Pump W / Bracket Insert Awl Into The Pump Bracket Wire Harness Plug, with Red Locking Tab — Page 36 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 37: Electric Heating Element

    If the boiler tank is above 158°F, the Aqua-Hot is at operating temperature and requires no heat. Troubleshooting: 3. Verify the Electronic Controller is sending 12 Volt DC to NOTE: For continuous domestic hot water to be present, the the A.C.

  • Page 38: Electric Heating Element

    Reinstall the AC access cover. A. Disconnect all power supplies. Refill the Aqua-Hot’s boiler tank with the antifreeze and B. Remove the AC access cover. water heating solution. C. Remove all wires from the electric heating element.

  • Page 39: Relay

    COULD CAUSE SERIUOS DAMAGE OR PERSONAL INJURY Disconnect the AC power source to the motorhome Ensure that the Aqua-Hot has been completely shut (unplugging from shore power or shutting off the gener- down and that all power sources have been disconnect- ator).

  • Page 40: Section 6: Electronic Controller General Facts

    Electronic Controller Overview The electronic controller is an electronic circuit board that Aqua-Hot unit. Indicator lights on the front panel will illu- controls the electrical functions of the Aqua-Hot heating minate red if there is a short circuit, overload, or fault condi- system.

  • Page 41: Secondary 12 Volt Dc Battery Connection

    Secondary 12 Volt-DC Battery Connection: The electronic controller is equipped with two 12 Volt-DC ensure that the Aqua-Hot will be protected in the event that power source connections, which allow for a secondary 12 the primary power is interrupted while the diesel-burner is Volt-DC battery connection.

  • Page 42: Low Voltage Reset Feature

    Low-Voltage Reset Feature: button on the electronic controller (use a thin, straight, non- Whenever the Aqua-Hot’s DC power is interrupted, for long- metallic object to access the button through the faceplate) or er than 5 minutes, the “low battery voltage fault” red indica- by turning off the diesel-burner switch on the interior switch tor light on the electronic controller will illuminate.

  • Page 43: Replacement Procedure

    AILURE TO DISCONNECT ALL POWER SUPPLIES AND Ensure that the pin jumpers are properly configured for TO ALLOW THE HEATER TO COOL BEFORE SERVICING an Aqua-Hot 450-DE; reference information in this sec- COULD CAUSE SERIOUS DAMAGE OR PERSONAL INJURY tion for proper pin-jumper configuration.

  • Page 44: Section 7: Electronic Controller Indicator Lights Electric Heating Element Status Indicator Light

    AC illuminated because an adequate level of antifreeze and water relay. heating solution within the Aqua-Hot’s boiler tank exists. When illuminated (red only), three possible issues exist - the Heating Zone Status (1-5)

  • Page 45: [Circulation] Pump #1 Indicator Light

    Pump #3 - Stir Pump This light illuminates red when the Aqua-Hot is shut down due to excessive DC voltage (over 14.8 Volts) and/or the This indicator light shows the status of the stir pump by illu- electronic controller has overheated.

  • Page 46: Section 8: Diesel-Burner Overview

    IESEL URNER Diesel-Burner Overview The Aqua-Hot’s diesel-burner is a device that ignites a mix- from the flame is transferred to the antifreeze and water heat- ture of diesel fuel and air within a controlled setting to serve ing solution where it can be used for each system of the Aq- as a heat source.

  • Page 47: Diesel-Burner Overview

    8: D ECTION IESEL URNER Figure 28 — Page 47 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 48: Diesel-Burner Operational Flow Chart

    The Motor (#2), which turns the unassisted. Combustion Air Blower (#5) NOTE: and drives the Fuel Pump (#14), When the Aqua-Hot’s Diesel Burn- will begin to operate. er is switched OFF by the VDC/ The combustion process will con- NOTE:...

  • Page 49: Diesel-Burner Operational Overview

    Use the tions are experienced, use this sequence of operating events “KEY” provided to understand each symbol shown. Figure 29 — Page 49 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 50 8: D ECTION IESEL URNER Figure 30 — Page 50 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 51 8: D ECTION IESEL URNER Figure 31 — Page 51 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 52: Detaching The Diesel-Burner

    Diesel-Burner and disconnect power could result in serious bodily injury. CAUTION! Be sure to clamp off the Fuel Supply and Return lines at the ports on top of the Aqua-Hot prior to beginning this replacement procedure. Step 1: Turn Off the Diesel Switch Figure 32 1.
  • Page 53 Step 3: Disconnect the Diesel Burner’s Controller Figure 34 1. Locate the Diesel-Burner’s Controller and disconnect both plugs. Step 4: Remove the fuel lines from the Aqua-Hot Figure 35b Figure 35a 1. Locate where the fuel lines on the diesel burner 2.

  • Page 54: Reattaching The Diesel-Burner

    Step 5: Remove the Diesel Burner from the Aqua-Hot Figure 36a Figure 36b 1. The Diesel-Burner is secured to the Aqua-Hot with two nuts that can be loosened, and swung out of the way by using a 10mm socket wrench with a 10 inch long exten- sion.
  • Page 55 Step 1: Reattaching the Diesel Burner to the Aqua-Hot Figure 37a 1. The Diesel-Burner is secured to the Aqua-Hot with two eye-bolt nuts that can be swung into place, after the diesel burner has been properly aligned and set in place.
  • Page 56 CAUTION! Be sure to remove the clamps, off of the Fuel Supply and Return lines at the ports on top of the Aqua-Hot prior to start- ing the diesel burner, or serious damage will occur to the diesel-burner’s fuel pump.
  • Page 57 Step 4: Reinstall the Access Cover NOTE: The access cover must be installed prior to operation as a safety switch exists, which will prevent the Aqua-Hot from operating whenever the access cover is not properly installed. Figure 40b Figure 40a 1.

  • Page 58: Section 10: Diesel-Burner Components And Repair Information Diesel-Burner Component Overview

    10: D ECTION IESEL URNER OMPONENTS Figure 41 — Page 58 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 59: Motor

    A. Using a volt meter, check for 12 Volt-DC on the NOTE: The Aqua-hot 600 Series is equipped with a 20A JP4 plug, on the B4 + pin (red wire #3). If no Fast Blow Fuse, located on the red #20 wire, between the power is present verify the electronic controller is electronic controller and the diesel burner controller’s B-...
  • Page 60 Figure 43 Disconnect the motor’s black (+) and brown (-) wires from the C-plug harnesses black (+) and brown (-) wires. — Page 60 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 61 Reinstall a clutch half on both the new motor’s shaft nect the Diesel-Burner’s power supply before de- and the combustion air blower shaft. Attach the taching the Diesel-Burner from the Aqua-Hot. Fail- motor and flange assembly, with the recessed edge ure to turn off the Diesel-Burner and disconnect of the motor flange in-line with the wiring access power could result in serious bodily injury.

  • Page 62: Motor

    10: D ECTION IESEL URNER OMPONENTS Motor Replacement Procedure: (continued) — Page 62 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 63: Flame Sensor

    C-plug harness wires. Figure 45 Flame Sensor Green Wire Blue Wire — Page 63 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 64: Flame Sensor

    C-plug harness’ green and vio- burner, in section 9 of this manual. let wires, and remove flame sensor. Figure 46 — Page 64 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 65: Ignition Electrodes

    If it is missing, replace the electrode boot. Figure 47 — Page 65 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 66: Fuel Nozzle

    Fuel Nozzle Component Test: Figure 48 1. Follow the directions for detaching the diesel burner, in section 9, of this manual. — Page 66 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 67 A partially plugged orifice will restrict fuel flow, which will affect the combustion process of the diesel-burner. Figure 49 — Page 67 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 68: Fuel Solenoid

    Using an 8mm wrench, remove the lock nut and flat washer from the end of the fuel solenoid shaft and then pull the fuel solenoid away from the nozzle — Page 68 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 69: Fuel Pump

    145 PSI, A. Check the motor home fuel tank for fuel. If the which is required for proper fuel atomization. Ref- fuel level is below 1/4 the Aqua-Hot diesel erence the illustration below for a basic overview burner will not operate.
  • Page 70 9 of this manual. NOTE: Do not adjust the fuel pressure regulator of the new fuel pump, as it has been factory preset. — Page 70 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 71: Fuel Pump

    10: D ECTION IESEL URNER OMPONENTS Fuel Pump: (continued) Figure 52 — Page 71 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 72: Bearings

    C-plug harness wires, prior to removing. Remove the protection cap from the diesel-burner so that the motor and clutch halves are exposed. Figure 53 — Page 72 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 73 Discard the retaining nut, steel drive gear, snap rings, bear- ings, spacer tube, and washers, as replacements are provided in the new bearing kit. — Page 73 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 74 Figure 55b Figure 55a .018 - .020 — Page 74 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 75: Ignition Coil

    4. Ensure the electrode boots are not broken inside the igni- (-) wires from the C-plug harness’ yellow (+) and tion coil wires. brown (-) wires. Figure 56 — Page 75 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 76: Ignition Coil

    Lift the ignition coil and disconnect its wires from burner and test for proper operation. the C-plug harness wires, prior to removing. Figure 57 — Page 76 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 77: Controller

    NOTE: Before troubleshooting the Diesel Burner Control- Locate the diesel-burner controller’s B-plug and C- ler, verify that the Aqua-Hot’s Electronic Controller has voltage at both the C1(orange) & C7(white) wires on the JP4 plug. Insert the probes of a DC voltmeter into the B Plug.

  • Page 78: Controller

    C-plug and B-plug ports facing downward. Failure to do so, will result in moisture collecting in the ports and potential damage to the diesel-burner controller’s internal circuitry. — Page 78 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 79: If The Aqua-Hot Is Black Smoking

    Impeller Fan Not Gapped Properly The impeller needs to be gapped at 3-5 thousands or tighten fan down until it rubs, back it off ¼ turn. — Page 79 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 80: If The Aqua-Hot Is Blue/White Smoking

    Intermittent Ignition Coil - If the coil doesn’t turn on, the fuel sprays for 20 seconds, before the photo eye shuts the fuel off. — Page 80 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 81: If One Of The Aqua-Hot's Heating Zones Will Not Get Hot

    Not enough Heat Exchangers installed Heat Exchangers improperly installed. 2. If Fans and Pumps are Running A. Stuck Check Valve B. Kinked Line C. No Antifreeze in system — Page 81 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 82: If There Is A Lack Of Domestic Continuous Hot Water

    3. The diesel burner must be on for continuous hot water, the electric element is for lim- ited use only. 2: Things to test for a lack of hot water problem. 1. Aqua-Hot Heater Bypassed 2. Outside Water Faucet is left on. 3. Washing Machine Valve has gone bad 4.

  • Page 83: If There Is Antifreeze Leaking

    NOTE: To find an antifreeze leak, the system must be Hot (up to operating temperature) Or pressurized to 15PSI. Inspect the following components on the Aqua-Hot Heating System for Leaks: 1. On the Front-Side of Aqua-Hot - 1. Fluid Level Sensor a.
  • Page 84 Note: If no leaks are found on the Aqua-Hot, it is possible that there is a leak within the motor home. Check all Heat exchangers, connections, and tubing for leaks.

  • Page 85: Appendix A: Wiring Diagram

    A: W 2011 PPENDIX IRING IAGRAM MANUFACTURED BEFORE JANUARY — Page 85 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 86 A: W – PPENDIX IRING IAGRAM 2011 2011 MANUFACTURED ETWEEN ANUARY THRU UGUST — Page 86 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 87 A: W – 09/01/2011 PPENDIX IRING IAGRAM MANUFACTURED FTER — Page 87 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 88 NFORMATION Because all Aqua-Hot heating systems are designed to operate only when there is an adequate supply of DC (Direct Current) voltage, it is imperative that the proper wire gauge be determined and used for the DC power supply and ground wires. This bulletin address- es how to determine the DC amperage draw of the heating system, including heat exchangers, then, how to determine the proper wire gauge based upon those findings for a specific application.

  • Page 89: Appendix B: Wire Gauge Chart

    PPENDIX AUGE NFORMATION For example, an Aqua-Hot 600-D with six Aqua-Hot Cozy heat exchangers has a total amperage draw of 23.38 amps. Determining the Proper Wire Gauge: 1. Measure the total length of the wire required for the distance between the vehicle’s battery and the elec- tronic controller for Aqua-Hot models 450-DE, 450-DM, 525-D, 600-D, and 675-D and the heater itself for the Aqua-Hot 375-D model.
  • Page 90 Step 2: Install fuel line bypass fittings onto the diesel burner. Figure C2 1/4” Fuel Tube unions 1. Locate the 1/4 “ fuel tube unions on the bottom side of diesel burner. — Page 90 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 91 2. Using a 13mm and a 9/16” wrench remove Steel Fuel lines from the diesel Burner Figure C4 3. Using a 13mm and a 9/16” wrench install the fuel bypass fittings onto the diesel Burner — Page 91 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...

  • Page 92: Appendix C: Fuel Pressure Check And Adjustment

    1. Using a 5/8” and a 3/4” wrench remove the fuel nozzle. Figure C6 2. Using a 5/8” and a 3/4” wrench install the fuel pressure gauge. — Page 92 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 93 2. Turn the diesel burner switch to the on position. A pressure will register on the fuel pressure gauge once the fuel solenoid opens (after approx. 10-20 seconds. — Page 93 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 94 2. Turn the diesel burner switch to the on position. A pressure will register on the fuel pressure gauge once the fuel solenoid opens (after approx. 10-20 seconds. — Page 94 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 95 NOTE: If the fuel pressure cannot be adjusted refer to the fuel pump section in section ? Of this manu- al for troubleshooting tips. — Page 95 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 96 B. Is the Diesel Fuel liquid or Jelled? C. Are the electrodes properly adjusted? NOTE: The Aqua-Hot can continue to be used for interior zone heating once the domestic water heating system D. When was the last time an Annual Service has been drained and winterized.

  • Page 97: Appendix D: Extreme Cold Weather Operation

    If there is a lack of interior Heat: Note: The 120 Volt-AC Electric Heating Element is the Aqua-Hot’s secondary heat source for heating both the interior and/or the domestic hot water during low heat- ing demand situations (such as when moderate ambient temperatures exist and/or when there is a low demand for domestic hot water).

  • Page 98: Appendix E: Aqua-Hot Annual Maintenance

    TO ALLOW THE HEATER TO COOL BEFORE SERVICING water heating solution within the expansion tank should only COULD CAUSE SERIOUS DAMAGE OR PERSONAL INJURY be checked when the Aqua-Hot is at maximum operating temperature. To keep the Aqua-Hot running smoothly, it is recommended to have the diesel-burner tuned up annually.
  • Page 99 2. Using hose pinch off pliers, clamp off both fuel lines going to the fuel filter. Reference Thermostat figure E2. Figure E3 Connector Figure E2 Diesel Burner Controller Plugs — Page 99 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 100 AINTENANCE Aqua-Hot Maintenance Procedure: Step 4: Remove The Diesel Burner CAUTION! Be sure to clamp off the Fuel Supply and Return lines at the ports on top of the Aqua-Hot prior to beginning this replacement procedure. Figure E4a Figure E4b 1.
  • Page 101 Diesel Burner’s white Thermostat Plug 4. Carefully pull the Diesel-Burner away from the Aqua-Hot 4 to 5 inches before rotating the burner, and then remove. NOTE: To remove the diesel burner, it may be necessary to disconnect the control and hi limit thermo- stats from the diesel-burner’s white thermostat plug.
  • Page 102 Failure to do so will mately 16 inches. reduce the Aqua-Hot’s heat transfer capabilities. NOTE: If the heat transfer tabs are excessively sooty, it may be necessary to vacuum the soot out of the heat transfer tabs.
  • Page 103 A. Inspect the outer ring that the photo disc seats against for signs of warping. B. Inspect the back side of the Air Swirler for signs of warping between screws. — Page 103 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 104 Combustion Chamber Gasket Air Swirler 1. Reinstall the Combustion Chamber Assembly and the Air Swirler into the Aqua-Hot. Please note: It will be necessary to replace the combustion chamber gasket, anytime the combustion chamber is removed. — Page 104 —...
  • Page 105 Broken or cracked “Ears” Harness & Ignition Coil Wires - due to over tightening of eyebolts. - crack or bare wires - Hard or brittle wires — Page 105 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 106 A. For light dirt, dust, and/or carbon deposits, simply wipe off the flame sensor with a soft cloth. B. Should heavy carbon deposits be present, completely remove the flame sensor from the photo disc and clean with brake cleaner. — Page 106 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 107 Be sure to reattach the diesel-burner head prior to switching the heater ON. Failure to do so may result in ignition of the diesel-burner and serious bodily injury. — Page 107 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 108 Lay the clamp’s beveled side down on a solid flat surface and align the thick end of the punch at dead center. Tap the punch lightly until the retaining clamp returns to proper form. 4. Remove the electrode adjustment gauge. — Page 108 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 109 NOTE: When reinstalling the diesel burner be careful not to damage the photo disc or bend the electrodes. Also, be careful to not pinch any wires between the burner and the Aqua-Hot Tank. 1. Align the Diesel-Burner with the Aqua-Hot, using the alignment tabs welded on the Aqua-Hot.
  • Page 110 CAUTION! Be sure to remove the clamps, off of the Fuel Supply and Return lines at the ports on top of the Aqua-Hot prior to start- ing the diesel burner, or serious damage will occur to the diesel-burner’s fuel pump.
  • Page 111 Step 15: Re-Install the Aqua-Hot Access Cover NOTE: The access cover must be installed prior to operation as a safety switch exists, which will prevent the Aqua-Hot from operating whenever the access cover is not properly installed. Figure E15a Figure E15b 1.

  • Page 112: Appendix F: Winterization Process

    Not winterizing the Aqua-Hot when freezing temperatures this procedure for both the hot and cold faucets. are present will result in serious damage to the Aqua-Hot’s Domestic Water Heating System. Also, be sure to use an Turn off Demand Water pump and remove the hose and re- FDA approved, “GRAS”...

  • Page 113: Appendix G: Filling/Draining The Aqua-Hot

    Department at 1-800-685-4298. FDA shall be used in the Aqua-Hot’s hydronic heating NOTE: To Fill the Aqua-Hot it is recommended to use a system. Failure to use the above specified antifreeze type fluid transfer pump, and pump the antifreeze into the Boiler could result in serious injury or death.
  • Page 114 10. Open the drain valve and Turn the fluid transfer pump on, and fill the Aqua-Hot with the 50/50 mixture of antifreeze and water heating solution until the Low Tank-Level Cutoff Light, on the Electronic Control Board is extinguished, reference Figure 2.
  • Page 115 G: F PPENDIX ILLING RAINING THE OT WITH HEATING SOLUTION Figure G4 Zone 1 Zone 2 Circulation Pump Circulation Pump — Page 115 — — Page 115 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 116 Open the Aqua-Hot’s drain valve located at the front of bay floor prior to beginning this antifreeze and water heating the heater. Reference Figure G5.
  • Page 117 — Page 117 — ® © March 2012 Aqua-Hot 450-DE4 Hydronic Heating System Service Manual—Rev. E...
  • Page 118 AHE-450-DE4 SERVICE MANUAL 15549 East Highway 52 | Fort Lupton, CO 80621 Toll free: 800.685.4298 | phone: 303.659.8221 | fax:303.857.7881 www.aquahot.com...

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