The last thing you want when you’ve invested thousands in a solar system is to wind up with subpar performance and unexpected repairs. Worst still, many installers can be hard to reach when problems arise. This is why knowing about the common solar installation problems and finding a quality installer from day one is important.
Solar fact: The Clean Energy Regulator found that 18.6% of randomly inspected solar systems installed in 2024 were rated substandard, while 0.4% were rated unsafe. Keep in mind a substandard rating does not mean a system is unsafe, but may affect performance or lead to problems later on.
In our 15+ years in solar, our team at Teaslec has been called in to repair many systems installed by other providers. A common pattern is property owners choosing the cheapest quote, only to face poor performance, faults or repair costs down the track. These are some of the most common solar problems our electricians regularly come across and the checks that can help you avoid them.
1. Poor Solar System Design & Sizing
A recent study of people looking to install solar by the Australian Government found more than half of people found choosing a system type and size one of the most difficult steps. While it’s a problem a solar installer should help with, it’s all too common to see systems that are too big or too small for a property’s electricity use, roof and future needs. This is a problem because:
- Too small and you may need to buy more electricity from the grid than expected or outgrow the system as your needs change.
- Producing more than you can use or export may mean your system sends large amounts of power to the grid for a lower return or has some generation restricted by export limits.
For solar to be worth it, you need the right-sized system.
“Two homes can have almost identical power bills and still need different solar systems. One may use most of their electricity during the day, like someone who works from home, while someone else may use more at night. That’s why sizing a system should never be completely based on the bill alone.”
How to Avoid Poor Solar System Design
Before recommending a system, the installer should be checking:
- Recent electricity bills and smart meter data.
- How much power you’re using during the day.
- Available roof space, direction and shading.
- Local network and export limits.
- Your plans for electric hot water, machinery, air conditioning, electric vehicles and other electric appliances.
To help avoid this common solar problem, ask for the expected generation and savings to be included in your quote, along with a clear explanation of why that system size is suited to your property.
2. Poor Panel Placement & Unaddressed Shading
Even a roof with plenty of space for solar can still have poor panel placement. If panels are installed too close to a chimney, under an overhanging tree or on a section of roof that gets less sun, you may generate far less power than expected.
Plus, shading can cause other problems too. If the panels are connected in a string, shade on one panel may reduce the output of the others connected to it.
How to Avoid Solar Panel Placement Problems
To help avoid problems with your solar placement, ask to see a proposed roof layout before accepting a quote. It should show you:
- Where each panel will sit.
- Which direction each panel will face.
- Shading caused by trees, chimneys or nearby buildings.
- How the proposed layout affects expected generation.
Sometimes shade can’t be avoided. In this case, the installer should explain how the system manages this. They may separate shaded panels into another string or use optimisers or microinverters. Solar Victoria recommends working with an installer to design the system so shading has as little impact on expected generation as possible.
A Shaded Roof Doesn’t Always Rule Out Solar
After being told by several other solar companies that their roof was too shaded and not suitable for solar, a homeowner turned to Teaslec. We took a closer look and identified a way to make the installation work. It’s a good reminder that shade isn’t always an automatic no. The roof layout and proposed system design can change what is possible.
3. Panel Mounting & Poorly Sealed Roof Penetrations
Installing solar involves people on your roof, tiles being lifted and mounting equipment getting fixed into place. This leaves room for cracked tiles, poorly sealed fixing points or unsuitable mounting hardware that can leave your roof open to leaks.
There’s also the problem of a roof not being in great condition to start with. Putting a system expected to last decades onto a roof that’s going to need replacing soon may mean paying to remove and reinstall the panels later. You don’t want either problem.
A lot of the solar repairs Teaslec attends are problems that could have been prevented before installation even began. Saving money on the original quote offers little value if damaged roofing, unsuitable mounting or poor workmanship needs to be repaired later.
How to Prevent Roof Leaks from Solar & Mounting Issues
Before you even think about solar, you should always have your roof checked, having any brittle or cracked tiles, rust, existing leaks or damaged roof sheets repaired first, if needed.
Also ask any prospective solar installers:
- If the roof is suitable for solar in its current condition.
- Which mounting system will be used for your roof type.
- How existing and accidental damage will be documented.
- What their workmanship warranty covers if a leak does develop.
4. Unsafe Wiring & Poor Cable Management
According to the Clean Energy Regulator, wiring is one of the most common solar installation problems and causes of substandard work. However, as cabling is typically hidden under panels, it’s usually hard to see when there’s actually a problem.
“It’s quite common for people to not know a new solar system in Victoria cannot be switched on until it’s been checked by an independent Licensed Electrical Inspector, by law. This can help pick up on wiring problems you can’t see.”
Over time, any loose cables or wires left resting on the roof can get exposed to sharp edges and weather, causing potential wear and damage. Plus, poor connections may also cause faults or stop the system performing properly.
How to Avoid Solar Wiring Problems
To help avoid wiring problems, make sure you choose an accredited installer who works for a Registered Electrical Contractor. After installation:
- Ask for photos of the wiring beneath the panels.
- Confirm the cables have been secured and are protected.
- Check that an independent electrical inspector attended.
- Keep your Certificate of Electrical Safety.
Solar tip: Energy Safe Victoria actually states new solar systems cannot be switched on until it’s been checked by an independent Licensed Electrical Inspector. You must also receive a Certificate of Electrical Safety once the inspection is done.
5. Installing the Inverter in the Wrong Spot
In our 15+ years in solar at Teaslec, we’ve seen that inverters installed in the wrong spot are more prone to overheating, not performing as well as they should and wearing out years before they should. An inverter’s job is to convert the electricity generated by the solar panels into electricity your home or business can use, and it often works hardest during the warmest part of the day.
So, installing it in direct afternoon sun, without enough airflow or where it’s exposed to rain can place it under unnecessary stress, as well as having potential Wi-Fi connection issues. This is why our process at Teaslec involves confirming the proposed inverter location as part of the design rather than leaving the decision until installation day, allowing us to check exposure, airflow, accessibility and connection requirements before work begins.
How to Choose the Right Inverter Location
Before installation day, confirm exactly where your inverter is going to be placed. The installer should choose a place that:
- Is shaded from direct sun and protected from rain.
- Has enough space around it for airflow.
- Can be safely accessed for servicing and repairs.
- Is close enough to connect to the monitoring system.
- Follows the manufacturer’s installation instructions.
Frequently Asked Questions About Solar Installation Problems
Planning a solar panel installation?
The good news is that most of these common solar installation problems can be avoided with careful system design, quality workmanship and the right checks at every stage. With more than 15 years in solar, that’s the standard Teaslec brings to every installation.
Comparing solar installers in Victoria? Teaslec brings more than 15 years of installation and repair experience in the design, workmanship and aftercare of every system. Get a free quote for solar designed around your property, electricity use and future plans.
