1. Introduktion
This instruction manual provides essential information for the safe and efficient operation of your Webasto Thermo Top Evo 5+ auxiliary heater and the T91 HTM remote control system. This system is designed to pre-heat the interior of your Mercedes GLK X204 vehicle and its engine, offering enhanced comfort and reducing engine wear during cold starts.
Please read this manual thoroughly before installation and initial use. Proper installation and operation are crucial for the system's performance and your safety.
2. Pakkens indhold
The complete package for your Webasto Thermo Top Evo 5+ auxiliary heater system for Mercedes GLK X204 includes the following components:
- Webasto Thermo Top Evo 5+ Heater Unit
- Vehicle-specific installation kit for Mercedes GLK X204
- Webasto T91 Remote Control
- Webasto T91 Remote Control Receiver
- Associated wiring harnesses, fuel lines, coolant hoses, exhaust components, and mounting hardware.
- Installation and operating documentation.

Billede 2.1: Overview af det komplette Webasto Thermo Top Evo 5+ auxiliary heater kit, including the main heater unit, wiring, hoses, exhaust, and the T91 remote control system components.

Billede 2.2: Nærbillede view af Webasto Thermo Top Evo 5+ heater unit, showing its compact design and connection points.

Billede 2.3: De Webasto T91 remote control and its receiver unit, packaged in a box, ready for installation and pairing.
3. Opsætning og installation
Vigtig: Installation af Webasto Thermo Top Evo 5+ auxiliary heater system requires specialized knowledge and tools. It is highly recommended that installation be performed by a qualified professional or an authorized Webasto service partner to ensure correct function and safety.
The installation process typically involves:
- Mounting the Heater Unit: Securely mount the Thermo Top Evo 5+ unit in the designated location within the vehicle, typically in the engine bay or under the vehicle.
- Brændstoftilslutning: Connect the heater to the vehicle's fuel supply system. This involves tapping into the fuel line and installing a fuel pump.
- Coolant Integration: Integrate the heater into the vehicle's coolant circuit to allow for engine and interior pre-heating.
- Elektrisk tilslutning: Connect the heater and the T91 receiver to the vehicle's electrical system, ensuring proper fusing and wiring according to the vehicle-specific wiring diagram.
- Udstødningssystem: Install the exhaust pipe and muffler, ensuring proper routing and clearance from heat-sensitive components.
- T91 Remote Control Receiver Installation: Mount the T91 receiver in a suitable location, typically behind the dashboard or in the passenger compartment, ensuring good signal reception.
- Initial Start-up and Testing: After installation, perform an initial start-up and thorough testing of all functions to ensure correct operation and leak-free connections.
Refer to the detailed vehicle-specific installation documentation provided with your kit for precise instructions and diagrams for the Mercedes GLK X204.

Billede 3.1: Cover of the Webasto installation documentation, specifically for the Mercedes Benz GLK (X204) model, indicating the vehicle-specific nature of the kit.

Billede 3.2: A page from the Webasto installation documentation for the Mercedes GLK X204, detailing compatible engine types (e.g., 200 CDI, 220 CDI, 250 CDI) and estimated installation time (approx. 11 hours).
4. Betjeningsvejledning
De Webasto Thermo Top Evo 5+ auxiliary heater is controlled using the T91 HTM remote control. This remote allows you to activate and deactivate the heater from a distance.
4.1. T91 HTM Remote Control Functions
- Activation (ON): Press the "ON" button to start the heating process. The remote will provide feedback on the heater's operating status.
- Deactivation (OFF): Press the "OFF" button to stop the heating process.
- Rækkevidde: The T91 remote control operates at a distance of up to 1000 meters in optimal conditions.
- Status feedback: The remote control provides visual feedback on the heater's operational status.
The maximum heating duration is 60 minutes, after which the heater will automatically switch off. You can manually switch it off at any time using the remote control.

Billede 4.1: De Webasto T91 remote control, featuring clear ON and OFF buttons for easy operation of the auxiliary heater.
4.2. Kompatibilitet
The T91 remote control is compatible with other Webasto control units, including the Tele Start T100 HTM, the 1533 comfort timer, and the Thermo Call TC 3, allowing for flexible control options.
5. Vedligeholdelse
To ensure the longevity and reliable operation of your Webasto auxiliary heater, regular maintenance is recommended. Please consult the full operating manual for detailed maintenance schedules and procedures.
- Regelmæssig drift: Operate the heater for approximately 10 minutes once a month, even during warmer periods, to prevent components from seizing.
- Brændstofkvalitet: Ensure that the vehicle's fuel tank contains sufficient and appropriate fuel (Diesel) for the heater to operate.
- Visuel inspektion: Periodically check for any visible damage to hoses, wiring, or the exhaust system.
- Professionel service: It is advisable to have the heater system inspected by an authorized Webasto service partner at regular intervals, especially before the start of the cold season.
6. Fejlfinding
Hvis din Webasto auxiliary heater is not functioning as expected, consider the following common issues before seeking professional assistance:
- Heater does not start:
- Check the vehicle's fuel level. The heater will not operate if the fuel level is too low.
- Sørg for, at køretøjets batteri er tilstrækkeligt opladet.
- Kontrollér fjernbetjeningens batteri, og udskift det om nødvendigt.
- Verify that the remote control is within range of the receiver.
- Insufficient heating performance:
- Ensure all vehicle doors and windows are closed.
- Check the vehicle's climate control settings (e.g., fan speed, temperature).
- Usædvanlige lyde eller lugte:
- Immediately switch off the heater.
- Do not attempt to repair the unit yourself. Contact an authorized Webasto service partner.
For complex issues or error codes, consult the detailed troubleshooting section in the complete operating manual or contact an authorized WebAsto servicecenter.
7. Specifikationer
Technical specifications for the Webasto Thermo Top Evo 5+ auxiliary heater:
| Feature | Specifikation |
|---|---|
| Fabrikant | WebI forhold til |
| Model Type | Thermo Top Evo 5+ |
| Operation Voltage | 12 V |
| Nominel output | 5.0 kW |
| Brændstoftype | Diesel |
| Arbejdstryk | max. 2.5 bar |
| Webasto Part No. (Heater) | 9021036C |
| Webasto Part No. (Kit) | 1316617C |
| Serienr. | 4C1422195266 |
| Maximum Heating Duration | 60 minutter |
| Fjernbetjeningsmodel | T91 HTM |
| Fjernbetjenings rækkevidde | Op til 1000 m |
| Køretøjskompatibilitet | Mercedes GLK X204 (2.0L+ engine) |
| Estimeret installationstid | Ca. 11 timer |

Billede 7.1: Detaljeret view af Webasto Thermo Top Evo 5+ heater unit's label, displaying key technical specifications such as model type, operating voltage, rated output, fuel type, working pressure, part number, and serial number.

Billede 7.2: The product box label for the Webasto kit, showing the material/item number 1316617C, serial number 1422195266, and description as "Scope of Delivery TT-Evo 5+ Water Heater Diesel 12V" for Mercedes-Benz GLK 220/250CDI.
8. Garanti og support
Denne Webasto product is covered by the manufacturer's warranty. Please retain your proof of purchase for warranty claims. For specific warranty terms and conditions, refer to the documentation included with your product or visit the official WebI forhold til webwebsted.
For technical support, service, or warranty inquiries, please contact your authorized Webasto dealer or the point of purchase. Do not attempt to repair the unit yourself, as this may void the warranty and pose safety risks.





