Hyundai HY2000Si: What It Is and How to Use It Safely

The Hyundai HY2000Si is a small petrol inverter generator: a portable unit that makes mains power for lights, a fridge, a laptop or a caravan battery when the mains fails. It is rated at 1600W with a 2000W maximum output, and the distributor states it produces a pure sine wave, the type of supply sensitive electronics expect¹. It is an older model, newly redesigned for 2016, and the distributor's product page listed it as sold out when checked, so treat it as a secondhand or end-of-line buy rather than something you can order new today¹.

What it suits is modest, short-term backup: a few lights, a fridge, charging phones and a caravan battery, or running a caravan's 230V sockets through the fly lead that comes with it¹. It is not a whole-house solution. Its 1600W rated output sets the ceiling on what you can run at once, and its 3.8 litre tank gives up to 9 hours¹.

Before you buy or use one, the safety rules matter more than the specifications. A petrol generator produces carbon monoxide, an invisible and odourless gas, so it must never run indoors, in a garage or in any enclosed space. The sections below cover what the machine can do, how long it lasts, how to run it on LPG, and how to use and store it safely.

What the HY2000Si is and who it suits

The HY2000Si is a compact, lightweight portable inverter generator built around the Hyundai HX125, a four-stroke 4.9hp recoil start petrol engine¹. Recoil start means you pull a cord rather than turn a key, so there is no battery to go flat before you can start it. Inverter output technology converts the engine's power into a steady mains supply, and the distributor states the output is a pure sine wave¹.

That combination suits a household that wants a modest amount of mains power for a few hours at a time, and a caravan or motorhome owner who wants to top up a leisure battery or run 230V appliances on a pitch. The distributor notes that the LPG conversion option is proving popular with caravan users¹. It also suits anyone who wants a generator light enough to move: at 20kg it is a one-person lift, though the same page also gives 21kg, so treat the weight as around 20 to 21kg¹.

It does not suit a household expecting to run an electric shower, an immersion heater or a whole house's circuits. Those draw far more than 1600W, and connecting a generator to your home's wiring is a separate job with its own rules. If you are weighing up a generator against a battery-based power station, the comparison of portable power stations and petrol generators sets out the trade-offs, and the guide to portable generators explains the different types.

Specifications at a glance

The figures below come from the distributor's product page. Where that page gives two different values for the same specification, both are shown, because the two listings disagree and neither has been ruled correct¹.

The two AC outlets are described on the same page both as 2 x 230V / 13A and as 2 x 230V standard 3 pin 13amp plug sockets, which amounts to the same thing for a UK household: ordinary three-pin sockets¹. The LED display shows voltage, frequency and hour count, so you can see what the machine is doing rather than guessing¹.

What it can power, and for how long

The rated output of 1600W is the figure to work from for anything that runs continuously. The 2000W maximum is headroom for a brief surge, such as a fridge compressor starting up. If you are unsure how a particular appliance's running and starting watts compare, the guide to watts, watt-hours and surge explains the difference, and what size generator you need helps you add up a household's load.

Run time depends on load. The distributor states up to 9 hours from a tank, and says it has seen over 12 hours from one tank under a light load¹. The same page also gives a tank of 3.8 litres in one place and 4.5 litres in another, and a run time of up to 8 hours in another, so plan on the shorter figure if you need certainty¹. For context, Honda's generator selection page describes its medium generators as giving up to three hours running time, which shows how much run time varies between machines and loads².

The ECO setting lowers engine revs when only a small amount of energy is required, which is how you stretch a tank when you are running a few lights and a phone charger rather than a fridge¹. The machine also has digital overload protection and low oil shutdown, so it will cut out rather than run itself into trouble¹.

Sockets, 12V charging and the caravan fly lead

The HY2000Si gives you three ways to take power out of it. The two 230V three-pin sockets take ordinary UK plugs for lights, chargers and appliances¹. The 12V / 8.3A DC output and the separate 1 x 12V 5Amp output are for charging 12V batteries directly¹. And the fly lead that comes with the machine plugs straight into a caravan or motorhome's power input, feeding the unit directly¹.

That last item is the reason caravan owners favour this model. A generator with a 12V charging output and a fly lead can top up a caravan battery without a separate charger³. If you are charging a leisure battery at home instead, the guide to leisure and LiFePO4 batteries covers what those batteries need, and 12V inverters explains the other direction, running mains kit from a battery.

For a household without a caravan, the 12V outputs are less useful, but they will charge a car battery or a spare leisure battery slowly. The 5Amp output is a trickle by battery-charging standards, so expect it to take time rather than revive a flat battery quickly.

Running it on LPG

The distributor states the HY2000Si can be converted to run on LPG, and that this option is proving extremely popular with caravan users¹. LPG has one clear practical advantage for backup: running time is no longer limited by the internal fuel tank, because you can use a bigger cylinder if you need a longer run⁴. The same point is made for Champion's dual-fuel generators, which is the general principle rather than anything specific to this machine⁵.

LPG also stores indefinitely in a sealed cylinder, unlike petrol, which degrades. A distributor's blog describes LPG generators as best suited to backup and long use⁶. That makes a converted HY2000Si a reasonable choice for someone who wants a generator that will still start after a year in the shed.

The safety rules for LPG are specific. Liquid Gas UK's guidance says to use hoses clearly marked as "High Pressure LPG" for direct connection to cylinders, or if the outlet pressure of the regulator exceeds 50 mbar⁷. The same body warns not to operate a regulator's mechanism using excessive force⁸. If you are new to cylinders and regulators, the guide to LPG cylinders and regulators covers the fittings, and LPG or petrol for emergencies weighs the two fuels.

Using it safely: carbon monoxide, fuel and electricity

A petrol generator produces carbon monoxide as it runs. It is invisible, has no smell, and can kill. The HY2000Si must never be run indoors, in a garage, in a shed, in a conservatory or anywhere the exhaust can build up, and it must be sited well away from doors, windows and vents. The guide to generator safety sets out the full rules, and carbon monoxide from generators explains the warning signs.

Fuel brings its own risks. Store petrol only in a proper container, away from the house and any source of ignition, and refuel only when the engine is cold and switched off. The guide to storing petrol at home covers the limits. On the electrical side, keep the total load within the 1600W rated output, use the machine's own sockets rather than daisy-chaining extension leads, and never plug a generator into a wall socket to backfeed the house. The guide to connecting a generator to your home's wiring explains why that is dangerous and what a proper changeover arrangement involves.

The machine's own protections help but do not replace care. Digital overload protection and low oil shutdown will stop it running into trouble, and the LED display lets you watch voltage and frequency¹. Check the oil before every run, using the oil fill jug supplied, and follow the operating manual that comes in the box¹.

Noise, storage and looking after it

At 60dB(a) at 7 metres, the HY2000Si is quiet for a generator but not silent¹. That is a working noise level, comparable to a lively conversation at that distance, and it will carry to neighbours on a still evening. Site it as far from their windows as from your own, and avoid running it late at night unless you have to. The guide to generator noise and neighbours covers the practicalities.

For storage, run the tank low or drain it if the machine will sit for months, because stale petrol is the most common reason a generator will not start. Store it somewhere dry and ventilated, not in the house, and keep the manual with it. The guide to storing a generator after a power cut sets out the routine, and will a generator start in cold weather covers winter starting.

The warranty is 3 years and requires registration, so register the machine when you buy it, whether new or secondhand with paperwork¹. Keep the receipt and the manual together.

Support, warranty and where to find one

The HY2000Si is an older model, redesigned for 2016 with a slimmer case, a compact inverter board and a full LED display¹. The distributor's product page listed it as sold out, with an expected delivery of 2 to 3 working days, when checked¹. That means you may struggle to buy one new, and a secondhand unit is the more likely route. Check the serial number and the year of manufacture, and ask whether the 3 year warranty has been registered and whether it transfers¹.

If you cannot find one, the current Hyundai range includes other inverter generators, and the Hyundai HY2250Si and Hyundai HY1000Si pages cover the alternatives in the same family. For a broader view of what is available, the backup power section sets out the options for a household, and the power cut guide covers what to do when the mains fails.