WLF Instantaneous Hot Water System User Manual

Published on August 19, 2026

Some Austrack caravans are fitted with a WLF Instantaneous Hot Water System. This system heats water on demand, meaning hot water is produced only when a tap is opened, rather than being stored in a tank. As a result, hot water supply is continuous (within system limits) and does not rely on stored volume.

Because this system operates differently from storage‑type heaters, it is important that owners understand the correct startup procedure, control operation, and temperature‑setting methods before use.

System Power and Safety Isolation

The WLF hot water system includes two separate power control points:

  1. A master on/off switch located on the hot water unit itself
  2. A wall‑mounted control screen used for everyday operation and temperature control

Appliance Master Switch (Kill Switch)

The on/off switch located in the hot water appliance acts as a master isolation (kill) switch. This switch:

  • Supplies or isolates power to the hot water system entirely
  • Should be switched off when the system is not required
  • Should be switched off during long‑term storage or servicing

This switch must be turned on before the wall controller will operate the system.

Wall Mounted Control Screen

The wall‑mounted control screen is used for:

  • Turning the system on and off for normal use
  • Setting the desired hot water temperature
  • Selecting temperature display units (°C or °F)

The system must pass a basic functional check each time the caravan and water system are set up for use.

Operating the WLF Hot Water System

Powering the System On

  1. Ensure the master on/off switch on the hot water unit is turned ON
  2. On the wall controller, touch the Power button
  3. The display will illuminate and show the current temperature setting

When powered on, the system is ready to heat water when a hot tap is opened.

Temperature Display Section (°C / °F)

  • Touch the °C / °F button to toggle between temperature units
  • The corresponding indicator on the display will confirm the selected unit

Austrack recommends using °C for consistency with other systems in the caravan.

Adjusting Water Temperature

  • Use the “+” and “–” buttons on the control screen to set the desired water temperature
  • Adjustable temperature range:
    • 35 °C (95 °F) minimum
    • 51 °C (124 °F) maximum

The selected temperature will be maintained automatically by the system while hot water is in use.

Turning the System Off

  • Touch the Power button on the wall controller to place the system into shutdown mode
  • If the hot water system will not be used for an extended period, also switch the master on/off switch on the unit itself to OFF

This ensures the system is fully isolated.

Methods of Using the WLF Hot Water System

The WLF Instantaneous Hot Water System may be used in two different operating methods, depending on user preference.

Method 1 – Point‑of‑Use Mixing (Recommended)

This method involves setting the heater to a higher output temperature and mixing hot and cold water at the tap.

Procedure:

  1. Set the controller temperature to approximately 46 °C (115 °F)
  2. Open the hot water tap
  3. Once hot water is flowing steadily, add cold water at the tap to achieve a comfortable temperature

Benefits:

  • More flexible temperature control
  • Familiar operation for most users
  • Better control at the shower or basin

Method 2 – Single‑Point Use (No Mixing)

This method involves setting the heater to the exact temperature required at the tap, without mixing cold water.

Procedure:

  1. Set the controller temperature to the desired bathing or washing temperature
  2. Open the hot water tap only
  3. The system will maintain the set temperature automatically

Important Note:
This method requires accurate temperature selection and may be more sensitive to flow rate changes.

Normal Operating Characteristics

During use, it is normal for the system to:

  • Require water flow to activate heating
  • Temporarily stop heating if water flow is interrupted
  • Adjust heating output based on flow rate and inlet water temperature

Hot water will only be produced when a hot tap is opened.

Service and Support

If the WLF hot water system:

  • Fails to power on
  • Does not maintain temperature
  • Shuts down unexpectedly
  • Displays abnormal behaviour

Austrack recommends contacting AOE RV Service Centre as the primary point of support. AOE RV Service Centre is familiar with Austrack plumbing and hot water installations.

If AOE RV Service Centre is not accessible due to geographic location, assistance should be sought from a suitably qualified caravan or RV service technician.

IMPORTANT NOTICE

The WLF Instantaneous Hot Water System is designed for controlled operation with clean water and appropriate power supply. Incorrect use, failure to isolate the system when not in use, or operation without water flow may result in damage not covered under warranty.

Always ensure the system is switched off when not required.

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