Reliable 3.3kW inverter power for larger caravans, motorhomes and off-grid leisure. When a 2kW gen...Reliable 3.3kW inverter power for larger caravans, motorhomes and off-grid leisure. When a 2kW generator is not quite enough for your setup, the next step up matters. The Hyundai HY3900Si delivers 3.3kW / 3300W maximum output and 3kW / 3000W continuous from a 144cc four-stroke engine. That extra headroom means you can run a caravan fridge, charge multiple devices, power lighting and still have capacity left over. The pure sine wave output keeps sensitive electronics safe, while the ECO mode stretches your fuel when full power is not needed. At 21.15kg, it is still portable enough for one person to move. This generator is ideal for Caravan and motorhome owners with larger power requirements, Glamping and off-grid leisure setups wanting dependable mid-range power, Boat owners and marina users needing portable shoreside power, Garden parties and outdoor entertaining where mains power is not available, Allotment holders and rural property owners needing seasonal off-grid power. This generator is NOT ideal for Lightweight camping trips where minimum weight matters - the HY2350Si is lighter and quieter, Extended use where longer runtime is critical, Users who need electric start convenience - this model uses recoil start only. What's In The Box: Hyundai inverter generator, Adjustment tools, User manual.
Key Features:
- 3.3kW Peak / 3.0kW Continuous Output – Mid-range inverter power ideal for larger caravans, motorhomes and off-grid leisure setups running fridges, lighting, TVs and device chargers together.
- Pure Sine Wave Safe Power – Clean, stable 230V inverter output protects laptops, televisions, games consoles and other sensitive electronics.
- Reliable 144cc 4-Stroke Engine – Air-cooled petrol engine with simple recoil start, designed for dependable seasonal and leisure use.
- 4L Fuel Tank with ECO Mode – Up to 6.3 hours at 10% load and 3.6 hours at 50% load; ECO mode reduces engine speed for better fuel efficiency and lower noise (67.6 dBA @ 7m).
- 16A Industrial Socket & Digital Meter – Includes 1x 16A blue socket, 12V DC outlet and 3-in-1 digital display for voltage, frequency and runtime monitoring, plus AC reset protection.
- 3 Year Hyundai Warranty – Supplied with a 3 year domestic warranty and 1 year commercial warranty for complete peace of mind.
The Hyundai HY3900Si is a 3.3kW inverter generator designed for users with larger power demands, such as caravan and motorhome owners, glamping sites, and off-grid leisure setups. Its key benefit is providing reliable, pure sine wave power for sensitive electronics while offering enough capacity to run appliances like fridges and multiple devices simultaneously. A potential caveat is that it uses a recoil start system, lacking electric start convenience.
All features
Model Part Number
HY3900Si
Brand
Hyundai
Extended Product Information
FAQs
What type of fuel does the HY3900Si use?
The generator uses unleaded petrol. Always use fresh fuel for optimal performance and storage.
How long can I run the generator on a full tank?
With the 4L fuel tank, runtime varies: up to 6.3 hours at 10% load and approximately 3.6 hours at 50% load. ECO mode can extend runtime.
Is the power output suitable for sensitive electronics like laptops?
Yes, the pure sine wave output is specifically designed to safely power sensitive electronics such as laptops, televisions, and gaming consoles.
Does this model have an electric start?
No, the Hyundai HY3900Si features a reliable recoil start system only.
What is the noise level of the generator?
The generator operates at approximately 67.6 dBA at a distance of 7 meters, with the ECO mode further reducing noise by lowering engine speed when full power is not required.
What is included in the 'What's In The Box' contents?
The box contains the Hyundai inverter generator, a set of adjustment tools, and the user manual.
What warranty is provided with this generator?
A 3-year domestic warranty is provided for private use, and a 1-year commercial warranty for professional applications.
Troubleshooting
Generator will not start.
Check fuel level and ensure fresh petrol is used. Verify engine oil level is correct. Ensure the fuel valve is open and the choke is set correctly for starting. If the issue persists, check the spark plug for fouling.
Low or no power output.
Ensure the circuit breaker has not tripped; reset if necessary. Check all appliance connections. If using the 12V DC outlet, ensure the load is within its capacity. Verify engine is running at the correct speed.
Engine runs but shuts off intermittently.
Check for fuel line blockage or air filter restriction. Ensure the generator is not overheating; allow it to cool. Monitor fuel cap vent for blockage.
Excessive smoke from the exhaust.
Check the engine oil level; overfilling can cause excessive smoke. Ensure the generator is not tilted excessively, which could allow oil into the combustion chamber.
Pros and Cons
Pros
Sufficient power output for larger leisure vehicles and off-grid setups.
Pure sine wave output protects sensitive electronics.
ECO mode enhances fuel efficiency and reduces noise levels.
Compact and portable for its power class.
Comprehensive 3-year domestic warranty.
Cons
Recoil start only, lacks electric start functionality.
Not ideal for lightweight camping due to its 21.15kg weight.
Extended runtime may be limited for very long periods without refueling.
Noise level, while managed by ECO mode, may still be a consideration for some environments.
Setup, Compatibility & Care
Setup:
Ensure the generator is placed on a stable, level surface in a well-ventilated area, away from direct sunlight and moisture.
Add the recommended type and amount of engine oil as per the user manual.
Fill the fuel tank with fresh, unleaded petrol.
Before starting, ensure no appliances are plugged in.
Compatibility:
The pure sine wave output is compatible with most sensitive electronics, including laptops, smartphones, TVs, and medical equipment (consult device manufacturer for specific power requirements).
Features a standard 16A blue socket for common caravan and camping appliances.
Includes a 12V DC outlet for direct charging of batteries.
Care:
Regular Maintenance: Refer to the user manual for scheduled maintenance, including oil changes and air filter cleaning.
Cleaning: Wipe down the exterior with a damp cloth. Ensure the unit is cool and switched off before cleaning.
Storage: For long-term storage, it is recommended to run the generator dry of fuel or use a fuel stabilizer to prevent carburetor issues. Store in a cool, dry place.