Könner & Söhnen KS 4000iEG S Dual-Fuel LPG/Petrol Inverter Generator
The Könner & Söhnen KS 4000iEG S combines petrol and LPG operation with a stable 230V pure sine wave inverter output. It provides 4.0kW rated power on petrol, with a 4.4kW maximum rating, while LPG operation reduces output by 10%. Electric and recoil starting, a sound-insulated enclosure and integrated wheels make it a practical portable power source when fuel flexibility matters.
Free delivery to mainland Great Britain only.
At a glance
| Petrol rated / maximum power | 4.0kW / 4.4kW |
|---|---|
| Approximate LPG rated / maximum power | 3.6kW / 3.96kW* |
| Output | 230V, 50Hz pure sine wave |
| Sockets | 2 × UK 13A household sockets — both 230V |
| Starting | Electric and recoil |
| Petrol runtime at 50% load | 7 hours 15 minutes** |
| Fuel tank | 13 litres |
*Calculated from the manufacturer's stated 10% LPG reduction. **Fuel consumption and runtime vary with load, fuel quality, season, altitude and generator condition.
Why choose the KS 4000iEG S?
- Petrol or LPG operation: choose fuel according to availability, storage and operating-cost requirements.
- Pure sine wave output: stable 230V, 50Hz power for compatible sensitive electronics.
- Electric and recoil starting: convenient starting options with a 1.6Ah starter battery.
- Economy mode: lowers engine speed at lighter loads to reduce fuel consumption and noise.
- Multifunction display: shows load, fuel level, voltage, frequency and operating hours, with status indicators.
- Useful connections: two UK 13A sockets, a 12V / 8.3A DC output, USB QC 3.0 and USB Type-C.
- Parallel-ready: compatible with the separately available KS PU1 parallel unit.
- Integrated transport system: wheels and a lifting handle make the enclosed generator easier to reposition.
Power, fuel and connections
Plan for the fuel in use
Use the 4.0kW petrol rating for normal petrol-load planning. LPG output is 10% lower, so plan around approximately 3.6kW rated power when running on LPG.
Dual-fuel setup
The LPG connection hose and reducer are included. A compatible gas cylinder is required and is not supplied with the generator. Never use petrol and LPG at the same time.
Parallel connection
The optional KS PU1 unit can connect two compatible inverter generators for increased output. Allow for the manufacturer's stated 0.2kW combined-power loss.
Technical specifications
| Voltage / frequency | 230V / 50Hz |
|---|---|
| Petrol rated power | 4.0kW |
| Petrol maximum power | 4.4kW |
| Approximate LPG rated / maximum power | 3.6kW / 3.96kW* |
| Maximum current | 17.4A |
| Power factor | 1 |
| AC sockets | 2 × UK 13A household sockets — both 230V |
| DC output | 12V / 8.3A |
| USB outputs | USB QC 3.0 and USB Type-C |
| Parallel connection | Yes — compatible KS PU1 unit required |
| ATS connection | No |
| Protection class | IP23M |
| Engine | KS 240i, 223cm³, single-cylinder four-stroke LPG/petrol, air-cooled |
|---|---|
| Engine power | 7.5hp |
| Starting | Electric and recoil |
| Fuel tank | 13 litres |
| Petrol runtime at 50% load | 7 hours 15 minutes** |
| Crankcase capacity | 0.6 litres |
| Starter battery | 1.6Ah |
| Packed dimensions (L × W × H) | 675 × 500 × 575mm |
|---|---|
| Net weight | 41kg |
| Noise level | 66dB(A) at 7m / 97dB(A) sound power |
*Calculated from the manufacturer's stated 10% LPG reduction. **Fuel consumption and runtime vary with load, fuel quality, season, altitude and generator condition.
What's included
- KS 4000iEG S dual-fuel inverter generator
- LPG connection kit with built-in reducer and 1.5m cylinder hose
- Spark plug wrench
- PH2 screwdriver
- Accessory case
- Operating instructions
Gas cylinder, petrol and engine oil are not included.
Before first use
- The generator is supplied without engine oil or petrol. Do not start it until the correct oil has been added.
- Use unleaded petrol rated 90–95 octane with no more than 10% ethanol.
- For LPG operation, check that the hose and connections are secure before opening the gas supply. Never operate on petrol and LPG simultaneously.
- Operate outdoors in a well-ventilated area on a firm, level surface, away from doors, windows and combustible materials.
- Read the owner's manual before starting, and connect appliances only after the engine is running steadily.
Manuals and downloads
Warranty
Manufacturer's warranty: 1 year or 1,000 operating hours, whichever comes first, from the date of purchase.
The warranty covers manufacturing defects, subject to the manufacturer's warranty conditions. Eligible faults may be repaired or the product replaced. Retain your proof of purchase and any completed warranty documentation supplied with the generator.
For help with a warranty claim, contact Energian with your order number, generator serial number and a description of the fault.
Frequently asked questions
Does it produce the same power on LPG?
No. The manufacturer specifies a 10% reduction on LPG, giving approximately 3.6kW rated power and 3.96kW maximum power.
Is a gas cylinder included?
No. The LPG connection equipment is supplied, but you need a compatible gas cylinder.
Can it start automatically during a power cut?
No. The current KS 4000iEG S specification does not include an ATS input. Contact Energian if you need an automatic backup solution.
Can two generators be connected together?
Yes. The separately available KS PU1 parallel unit can connect two compatible parallel-ready Könner & Söhnen inverter generators.
Energian support
For help choosing a generator contact Energian on 020 8064 0335 or info@energian.co.uk. For after-sales support, have your order number and generator serial number ready.