Operating manual for Webasto Thermo Top series pre-heating liquid heaters with timer 1533

Pre-heating Liquid Heater Webasto Thermo Top with Timer 1533 Manual

Heater Operation – General Instructions

1. Any claims will be considered by “Webasto” only if there is no evidence of non-compliance with this Manual and the installation instructions, or of work performed on the heater by non-certified “Webasto” specialists or using non-original spare parts.

2. The year of initial commissioning must be marked on the factory nameplate by erasing all other year markings.

3. Comply with operating conditions standard for automotive equipment. In particular, do not subject the heater or its components to immersion in water, mechanical impacts, high temperatures (above +85°C), humid air (above 95%), caustic substances, electrical discharges, etc.

4. Due to the risk of poisoning and suffocation, the heater must not be switched on (including by programmable timer or remote-control systems) in enclosed spaces (e.g., garages) unless equipped with exhaust ventilation.

5. At filling stations and in locations where flammable vapors and dust may be present (near fuel, coal, or grain storage, etc.), the heater must be switched off.

6. In the event of heavy smoke, unusual noises, or the smell of fuel from the heater, it must be blocked by removing the fuse and checked at a “Webasto” service center.

7. Only use the fuel specified on the heater’s factory plate (gasoline for gasoline heaters, diesel fuel for diesel units). Fuel and additives must comply with GOST standards, including for use in low-temperature conditions.

8. The coolant level in the circuit must meet the vehicle manufacturer’s specifications. The coolant must contain at least 20% antifreeze of brands approved by the vehicle manufacturer.

9. Switch the heater on once a month for 10 min with a cold engine and the vehicle fan at minimum power; it is also recommended to have it inspected annually, no later than the start of the heating season, at a “Webasto” service center.

(!) To avoid battery discharge, it is not recommended to switch the heater on several times in a row for a total of more than 60 min. After the heater has operated, the engine should run for at least as long as the heater.

Depending on configuration, the heater is controlled using a timer or a “Telestart” remote-control system (see the descriptions below).

The heater can operate in “winter” (heating) or “summer” (ventilation) mode. In heating mode, the heater warms the coolant in the vehicle’s liquid circuit; its circulation pump drives the coolant through the engine and the vehicle HVAC heat exchanger, and the control unit automatically starts the vehicle’s HVAC fan. In ventilation mode, there is no heating or circulation of coolant; only the HVAC fan operates, ventilating the cabin. See below for mode switching. At the factory, the heater is set to heating mode.

If the heater is in heating mode, set the vehicle HVAC to “warm” before switching on. If the HVAC fan is 3-step, set the control to step 1; if 4-step, set to step 2; if continuously variable, set to at least 1/3 power.

Operating a Heater Equipped with a Three-Program Timer

1. Current time / remaining operating time
2. Operation indicator (ventilation mode)
3. Step forward / display current time
4. Program selection
5. Program number
6. Immediate activation
7. Symbol for setting / displaying current time
8. Step back / display current time
9. Operation indicator (heating mode)

General Provisions

Dear customers!

We are pleased that you have purchased a Webasto product. We assume you received comprehensive information about the operation and maintenance of timer 1533 at the workshop/service center where it was installed.

In this manual we would like to provide additional clarifications on using timer 1533.

Timer 1533 is used for programming and controlling the operation of the Thermo Top automotive pre-heater (see the corresponding operating instructions) and complies with Directive 72/245/EWG (electromagnetic compatibility).

Timer Configuration

General Notes

The switch-on time can be set to any time of day with an accuracy of up to 1 min (from 00:01 to 24:00). Up to three switch-on times can be set simultaneously, but only one of them will be active.

The heater operating duration after a timer start can be set from 10 to 60 minutes

Programming the Timer

Changing values in the timer memory is performed in the setup mode. In this mode, the symbols on the display flash. If no button is pressed within 5 s after entering this mode, the value shown on the display is stored in memory. If the “<” or “>” button is held for more than 2 s, fast adjustment mode is activated.

Switching the Heater On

Manually: by pressing the immediate activation button (). The display shows the heating mode symbol () and the remaining operating time (extinguishes after 10 s).

Automatically: by pre-setting the switch-on time. The display shows the program number and the symbol for heating mode () or ventilation ().

Switching the Heater Off

Manually: by pressing the immediate activation button ().

Automatic switch-off: upon expiration of the automatic operating time. The display backlight turns off.

Setting the Current Time

(!) This setting is performed only when the heater is not operating!

Press and hold the “SET” button, then additionally press “<” or “>”. The current time is displayed, and its symbol ? flashes. Set the current time by pressing the “<” and “>” buttons. The set time is stored in memory after pressing the “SET” button or—without pressing any buttons—after the display backlight turns off.

(!) Attention! Do not forget to switch the timer between daylight saving and standard time!

Displaying the Time

Press the “<” or “>” button.

If the heater is operating, the remaining operating time is displayed.

Setting Modes (Heating / Ventilation)

(!) May not be available on all heater modifications!

Press the “SET” button. Press it again and hold: The display shows the icon of the current mode—heating () or ventilation ().

Select the required mode by pressing the “<” and “>” buttons while continuing to hold the “SET” button.

Setting the Switch-On Time

Press the “SET” button.

Within the next 10 s, press the “<” or “>” button; by pressing them, set the required switch-on time.

Switching between programs during programming is performed by pressing the “SET” button within 10 s.

Factory default program times: “1” – 06:00, “2” – 16:00, “3” – 22:00.

The factory setting of each program is cleared when the switch-on time stored in the respective program is changed. All factory settings are restored when the timer is disconnected from the onboard network and then reconnected.

Clearing Programs

Briefly press the “SET” button.

Selecting Programs

Press the “SET” button for up to 10 s until the desired program number appears on the display; the corresponding switch-on time and operating mode (heating icon () or ventilation ()) will also flash on the display.

Setting the Operating Duration

Press and hold the “SET” button, then additionally press “<” or “>”. The current time is displayed, and its symbol ? flashes.

Press and hold “SET” again, then additionally press “<” or “>”. The operating duration and operating mode (flashing heating icon () and ventilation ()) stored in the respective program are displayed.

Set the required operating duration by pressing the “<” and “>” buttons.

The set time is stored in memory after pressing the “SET” button or—without pressing any buttons—after the display backlight turns off.

Changing the Remaining Operating Time

While the heater is operating, the time for which it will continue to operate can be changed within the range of 10 to 60 min by pressing the “<” and “>” buttons.

Measures in Case of Heater Malfunctions

If a malfunction occurs, the electronic lockout is triggered: there are no indications on the display. In this case, check the fuses and plug connectors of the heater and eliminate any identified defects.

Then unlock the heater as follows: without switching it off, remove the fuse on its wiring harness (Thermo Top and Thermo Top T – blue 15 A; Thermo Top C and E – yellow 20 A, see figure), insert it after 3 s, switch the heater on from the timer or Telestart, remove the fuse again, and insert it after 3 s.

After installing the fuse, the heater should switch on. If it does not, contact a “Webasto” service center.

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