Almost always it's just the Wi-Fi link, not the system. Your panels and/or battery keep working without the internet - you just can't see the data.

Common causes: a new modem or router, a changed Wi-Fi password, the modem being switched off, or a weak signal out to the inverter. See the Reconnect Wi-Fi tab for step-by-step instructions.

• Weather and season - cloudy days and short winter days can drop output by more than half. This is normal.
• Shading - trees grow, and new buildings or antennas can shade panels.
• Dirty panels - dust, bird droppings, pollen and ash all cut output. See WattGuard panel cleaning.
• A fault - if output is near zero on a sunny day, check the inverter for a red light or error code and give us a call.

Take a photo of the screen or lights and note the time it happened. Some faults clear on their own (e.g. a grid voltage blip). If it's still showing after an hour, or keeps coming back, call or email us the photo and we'll diagnose it - often remotely.

Please don't open the inverter or battery, and don't switch isolators on and off repeatedly.

Only if your system was installed with backup (a backup gateway or backup circuits). If it was, your backed-up circuits will keep running from the battery.

Without backup, the system automatically shuts down when the grid goes down - this is a legal safety requirement so line workers aren't put at risk. It switches back on by itself when the power returns. Not sure what you have? Ask us.

• On cloudy days there may not be enough spare solar to charge it.
• Batteries keep a small reserve so they can protect themselves - they won't drain to 0%.
• If your plan has a free or cheap power window, the battery may be set to charge from the grid then.
• Mode settings (self-use, time-of-use, backup) change the behaviour. If you think the settings aren't right for your plan, call us and we'll check them.

Feed-in tariffs (what you're paid for exporting) are much lower than what you pay for grid power, so the biggest savings come from using your solar - run the dishwasher, washing machine, pool pump or hot water during the day.

Also check your retailer plan suits your setup - solar, battery or both. See Get the most out of it for the habits that matter most, or a WattGuard energy assessment for a proper review of your bills and tariff.

Rain does a fair job, but panels near farms, gravel roads, the coast, trees or birds can build up grime that cuts output. Please don't get on the roof yourself. See WattGuard for cleaning and health checks.

Usually yes - most modular batteries can have extra modules added, and it's often a quick job. See Add to your system and we'll check what your system can take and quote it.

Eureka if something's wrong: faults, error codes, warranty claims, Wi-Fi and app help, or adding a battery or EV charger. Warranty work is free.

WattGuard to keep it right: yearly solar and battery inspections, panel cleaning and monitoring plans. WattGuard is a separate business run by the same electricians, and Eureka customers get a discount.

Your paperwork has the exact details, but typically: 10 years on our workmanship, 10 years on the inverter and battery, and 25 years on panels and mounting - whichever of those your system has. If anything goes wrong, contact us first - we'll deal with the manufacturer for you.

One thing to know: some manufacturers require proof of regular servicing to honour their product warranty. WattGuard records every inspection and clean against your system so that history is there if you ever need it.

Follow the shutdown procedure on the sign installed at your switchboard and inverter - the order of switches matters. Only do this in an emergency or when asked by us.

Let us know. We can help transfer monitoring access to the new owner, and the warranties stay with the system.