Most users experience electricity savings of 20–40% on the portion of their bill related to geyser usage. With the SGCU and a properly sized solar collector, savings can be even higher, as a significant part of the heating is done by the sun instead of grid electricity.
Actual savings will depend on your geyser size, insulation, tariff structure, and how you configure your timers and temperature settings. The built-in monitoring and usage graphs can help you fine-tune your settings for even greater savings.

The GCU (Geyser Control Unit) is designed for standard electric geysers and focuses on optimising electric heating using timers, temperature control, and smart logic to reduce electricity usage.
The SGCU (Solar Geyser Control Unit) is specifically built for systems that include a solar collector and 12V DC circulation pump. It monitors both the collector and geyser temperatures and decides when to run the pump to move heat from the collector into the geyser.
The SGCU also supports features like freeze protection, solar/battery backup for the controller and pump, and advanced collector offset temperature, which are not present in the GCU.

If your geyser is not heating as expected, check the following:
Timers and schedules: Make sure your heating windows are configured correctly and active for the right days and times.
Target temperatures: Confirm that your day and night temperatures are set to levels that will give you enough hot water for your household.
Power supply: Check that the geyser isolator switch is ON and that there is power to the element (or inverter, if applicable).
App status and errors: Review your mobile app's timeline for any error messages or alerts that may indicate an element, sensor, or wiring issue.
If the issue persists, contact your installer or Energy Sense support with as much detail as possible so we can help diagnose the problem.

Yes. By using timers and smarter temperature control, the controller can shift most of your heating outside of peak tariff windows (where your tariff structure allows).
During load shedding, the controller automatically resumes operation when power is restored. If your geyser or SGCU is connected to an inverter and battery, you can also control how aggressively the geyser runs to protect battery life and reduce high demand during limited backup periods.
The SGCU in particular can keep using solar energy for heating (via the collector and battery-powered pump) even when Eskom is off, as long as the controller and pump have power from a small battery and panel or your inverter system.

Yes. Many users power their geysers from a hybrid inverter and battery system. In these setups, the GCU can be used to:
Schedule heating when solar PV production is high.
Limit geyser heating during low battery conditions or at night.
Reduce the strain on the inverter by managing how and when the element is used.
The SGCU can also integrate with inverter systems, using solar collectors to reduce the need for electric heating. We recommend working with your installer to design a configuration that balances comfort, savings, and battery protection based on your specific inverter and battery size.

Yes. The controllers are used in a wide range of environments, including:
Houses and townhouses
Guesthouses and Airbnbs
Small office buildings
Guard houses, staff quarters, and other outbuildings
As long as the geyser installation complies with local standards and the load ratings are within specification, the GCU/SGCU can be configured to match your usage patterns and business requirements.

Wi-Fi and internet are needed for:
Remote control and monitoring via the mobile app.
Firmware updates and new features.
Cloud-based logging and remote support.
However, once the controller and schedules are configured, the device can continue running its timers and safety logic locally even if the internet is down. You won't see real-time updates or be able to change settings remotely while offline, but your existing configuration will still operate on the controller itself.

Yes, on supported firmware, the controller can estimate your geyser's electricity usage and cost over time. By entering your local tariff (or blended rate), the system can:
Track how long the element runs.
Estimate kWh consumption based on the element rating.
Calculate a Rand value for daily, weekly, and monthly operation.
This helps you see the impact of changes you make to timers, temperatures, and solar usage, and gives a clear picture of how your geyser contributes to your overall bill.

The control unit requires minimal maintenance:
Visually inspect the enclosure and cable glands periodically for signs of water ingress, damage, or UV wear.
Check that sensors and probes remain securely in place and undamaged.
Monitor the app for any unusual behaviour or error messages.
Your geyser, valves, and safety components (like the pressure and temperature relief valve) should be checked on a regular basis in line with plumbing and electrical best practices. If you notice anything unusual, it's best to have the unit inspected by a qualified technician.

The GCU (Geyser Control Unit) is a smart device that provides 24/7 monitoring and control of your electric geyser. It replaces the basic on/off control with intelligent timers, temperature management, and safety features.
The GCU measures the geyser temperature and switches the element on or off according to your customized schedules and temperature settings. This ensures you have hot water when you need it while reducing unnecessary heating cycles and electricity consumption.

The main benefits of installing a GCU include:
Energy savings: Reduce electricity consumption by heating only when needed and avoiding continuous reheating.
Improved comfort: Maintain consistent, predictable hot water availability based on your household routine.
Safety: Benefit from extra temperature and runtime protection layers that help prevent overheating and identify abnormal behaviour.
Insight: Track your geyser's performance and approximate running costs over time.
Flexibility: Easily adjust schedules and temperatures via the app without climbing into the roof or changing hardware.
All of this helps reduce your monthly bill while protecting your geyser and extending its life.

The GCU is designed to be compatible with most standard electric storage geysers that comply with local installation standards. This typically includes 100L, 150L, and 200L units, and elements with standard power ratings used in South Africa.
Before installation, your installer will verify the geyser specifications, element rating, and wiring to confirm compatibility. If you have an unusual or non-standard setup, please contact our customer support team with your geyser's specifications.

The GCU includes multiple safety features:
Over-temperature protection: The controller will switch off the element if it detects abnormal or unsafe temperatures.
Maximum temperature limits: You can configure upper temperature limits to reduce scald risk and stress on the tank.
Smart runtime monitoring: The system can identify unusual heating patterns that may indicate a failing element, thermostat, or potential leak.
Additional logic layers: The GCU works together with existing geyser safety components (such as thermostats and safety valves), adding extra intelligence and monitoring to the system.
These features help protect both your geyser and your household by keeping operation within a safe, efficient range.

The GCU must be installed by a qualified, licensed electrician or approved installer who is familiar with geyser wiring and local regulations.
We do not recommend DIY installation because the controller interfaces with mains voltage and heating circuits, and incorrect wiring can lead to dangerous situations or damage to the unit.
Your installer will ensure that the GCU is correctly wired, configured, and tested, and can provide you with the necessary documentation and step-by-step guidance to ensure proper and safe installation.

The SGCU (Solar Geyser Control Unit) is a smart controller designed for geysers that use a solar collector and 12V DC pump to pre-heat water. It manages the circulation of water between the collector and geyser to maximise the use of solar energy.
The SGCU monitors both the collector and geyser temperatures. When the collector is sufficiently hotter than the geyser, the SGCU runs the circulation pump to move heat from the collector into the geyser. When conditions are not favourable, the pump is switched off to avoid cooling the geyser or wasting power.
The unit connects to your home WiFi for remote control through a mobile app, allowing you to monitor performance and adjust settings as needed.

The SGCU offers several benefits over a basic solar controller:
Smarter control: It uses advanced logic and configurable temperature differences to decide when to run the pump.
Remote monitoring and control: View temperatures, pump status, and system performance from your phone.
Solar and battery integration: Designed to work with small PV panels and 12V batteries, allowing continued operation during load shedding.
Safety and freeze protection: Includes logic for winter operation to help protect against freezing conditions.
Hybrid operation: Can work together with an electric element (via a GCU or compatible setup) for backup heating.
These features combine to maximise solar gains, improve reliability, and reduce reliance on grid electricity by harnessing renewable solar energy.

The SGCU is designed to work with a wide range of retrofitted solar collectors and standard electric storage geysers. Compatibility depends on factors such as:
Type and configuration of the collector system.
Presence of a 12V circulation pump and appropriate pipework.
Geyser type, size, and installation layout.
Your installer will assess your existing system and confirm compatibility. If you have any doubts, please contact our customer support team at info@energysense.co.za with details and photos of your setup.

The SGCU compares the temperature of the collector to the temperature of the geyser. When the collector is sufficiently hotter by a configurable temperature difference (for example, a set number of degrees), the SGCU starts the pump to move heat into the geyser.
Once the temperature difference drops below a threshold, or if the collector cools below the geyser temperature, the SGCU switches the pump off to avoid losing heat. This on/off logic helps ensure that the pump only runs when solar energy is actually available and beneficial.

In cold climates, water in exposed pipes and collectors can freeze and cause damage. The SGCU includes freeze-protection logic that can periodically circulate water through the system when temperatures approach freezing.
By running the pump in short intervals during very cold periods, the controller helps prevent stagnant water from freezing in the collector and exposed pipework, while still trying to keep energy usage as low as possible.
Your installer can fine-tune the freeze-protection settings based on your local climate and installation details.

With a small dedicated solar panel and 12V battery, the SGCU and pump can continue to operate even when Eskom is off. This means:
The controller can keep harvesting solar energy to heat the geyser during load shedding.
You don't lose a sunny day's worth of potential heating just because of a power outage.
The electric element will still be off if there is no grid or inverter power, but the solar side of the system can continue working independently as long as there is enough sunlight and battery charge.
This setup is ideal in areas with frequent load shedding and good solar potential.

Yes. In many installations, the SGCU manages the solar side of the system (collector and pump), while a GCU or similar controller manages the electric element.
This hybrid approach allows:
The SGCU to focus on maximising solar gains.
The GCU to provide backup or top-up heating from the element when solar alone is not sufficient.
Both controllers can be configured to work together, ensuring consistent hot water availability with maximum energy savings. Your installer will design the specific wiring and control strategy to suit your system.

On newer firmware revisions, the SGCU includes similar advanced logic to the GCU for detecting abnormal heating and runtime patterns.
If the controller observes that the system is reheating far more often than normal, or that temperature rise patterns look unusual, it can raise warnings that may indicate a potential leak, pipe issue, or inefficient operation.
These alerts help you pick up problems early, before they lead to high bills or damage. Check your app and firmware release notes to see which features your specific SGCU unit supports.

Correct sizing depends on your geyser volume, climate, and hot water usage patterns. A correctly sized system will typically:
Show a clear temperature rise in the geyser during sunny periods.
Have pump runtimes that match sunny hours, without constant running when conditions are poor.
Reach your target temperature reliably on most sunny days.
Your installer or solar specialist should calculate the appropriate collector area and pump capacity for your specific needs. If you notice weak performance or frequent under-heating, it may be a sign that the collector or pump sizing needs to be reviewed.

A solar geyser system with SGCU should be inspected regularly to ensure safe and efficient operation:
Check the collector for debris, dirt, or shading from trees and buildings.
Inspect external pipes and insulation for damage, UV wear, or leaks.
Ensure the pump, valves, and sensors are functioning correctly.
Review the app logs and temperatures to spot any unusual behaviour.
Your installer can recommend a suitable maintenance interval based on your climate and system design. Regular maintenance helps protect your investment and keeps your savings on track.

Basic tools required for installation typically include:
Screwdrivers (flat and Phillips)
Wire cutters and strippers
Drill and drill bits suitable for mounting the enclosure
Conduit, connectors, and cable glands (as specified)
Multimeter for verifying voltage and continuity
Conduit (16mm or 20mm).
Saddles to secure the Sprague.
Wood screws for mounting.
Your installer may use additional specialised tools based on your specific installation, roof type, and local regulations.

The control unit should be mounted in a location that is:
Close enough to the geyser and electrical connection points to minimise cable runs.
Sheltered from direct sun and driving rain.
Easily accessible for maintenance and inspection.
Installed upright and securely fastened to a solid surface.
Avoid mounting the unit in locations exposed to excessive moisture, heat, or water splashing. Proper mounting and orientation help protect the electronics and extend the life of the unit.

The temperature probe must be inserted into the dedicated geyser pocket or a suitable location as recommended by your installer. Ensure that:
The probe cable is not pinched, damaged, or exposed to sharp edges.
The cable is routed through appropriate conduit and glands to prevent water ingress.
The probe is fully inserted for accurate temperature readings.
On SGCU installations, additional probes may be used to monitor collector or pipe temperatures. These should be installed according to the system design and manufacturer guidelines for reliable readings.

The controller must be wired according to the supplied wiring diagram and local electrical standards. Typical connections include:
Mains supply from the geyser isolator (live, neutral, and earth).
Switched output to the geyser element (via a relay or contactor as specified).
Connections for sensors and control signals.
On SGCU systems, additional connections are made to the 12V pump and any auxiliary power (such as a small solar panel and battery).
All wiring must be done by a qualified electrician to ensure safety and compliance with regulations.

Yes, the control unit uses an enclosure designed for outdoor or semi-outdoor use when installed correctly. However, for best results it should be:
Mounted in a shaded area away from direct sun where possible.
Protected from direct spray and pooling water.
Installed with proper cable glands and drip loops to keep water from running into the glands or conduit.
Correct installation helps maintain the unit's IP rating and protect internal components from moisture and UV damage.

Installation time can vary depending on the complexity of the site and whether it is a new installation or a retrofit, but typical timeframes are:
GCU-only installation: Around 1–3 hours, depending on access and wiring complexity.
SGCU installation with existing collector: 3–5 hours, allowing time for pump, sensor, and hydraulic connections.
New solar conversions or more complex systems may take longer. Your installer will provide a more accurate estimate based on your specific setup.

When installed by a qualified and competent installer in accordance with local regulations and the geyser manufacturer's guidelines, the GCU/SGCU should not negatively affect your geyser warranty.
It is important that:
The geyser is installed with all required safety valves and components.
Electrical work complies with local standards.
Any modifications to the system are documented.
If you are unsure, consult your geyser manufacturer or installer regarding warranty implications before installation.

If your internet connection is down, the controller continues to operate using its locally stored schedules and settings. This means:
Timers will keep switching the geyser on and off as configured.
Safety and temperature controls continue to run.
You won't be able to monitor or adjust settings remotely via the app until the internet connection is restored.
Once connectivity returns, the app will resync with the controller and resume normal remote monitoring and control functions.

Firmware updates are typically delivered over the air (OTA) via your internet connection. When a new firmware version is available, the controller can download and apply the update automatically or after confirmation, depending on your settings.
To ensure you receive updates:
Keep the controller connected to your WiFi network.
Follow any prompts in the app related to updates.
Updates may include new features, performance improvements, and security enhancements. We recommend keeping your controller up to date.

Energy Sense provides ongoing support through:
Online documentation and guides.
Installer support and training.
Email and remote diagnostic assistance where possible.
Warranty support for eligible units.
If you experience any issues, you can contact us with details such as your controller type, installation date, installer details, and a description of the issue. This helps us or your installer resolve problems quickly and effectively.

The GCU and SGCU are supplied with a manufacturer's warranty that covers defects in materials and workmanship for a specified period from the date of installation or purchase.
Warranty terms typically require that:
The unit is installed by a qualified installer.
The installation complies with local regulations and manufacturer guidelines.
The controller has not been tampered with or modified in unauthorised ways.
For specific warranty details and terms, please refer to the warranty document provided with your unit or contact Energy Sense directly.

When requesting support, please provide as much detail as possible, including:
Controller type (GCU or SGCU).
Approximate installation date.
Installer details.
Photos of the controller, wiring, and geyser plate if safe to obtain.
A description of the problem, including when it occurs (time of day, weather conditions, load shedding events, etc.).
This information enables us or your installer to diagnose the issue faster and recommend the most appropriate solution.

Yes. One of the key benefits of the GCU/SGCU is that you can easily adjust timers and temperatures through the app without needing to access the physical unit.
You can:
Change heating windows to match your daily routine.
Set different temperatures for day and night.
Experiment with settings to find the best balance between comfort and savings.
If you are unsure about changing settings, your installer or Energy Sense support can provide guidance and recommendations specific to your home and usage patterns.

If you move into a home with a GCU/SGCU installed, you should:
Obtain any installation documentation or manuals from the previous owner or agent.
Contact Energy Sense or a qualified installer to help you claim or set up access to the controller in your own app account.
Review and adjust the schedules and temperatures to suit your own routine.
If you are moving out of a property with a controller, you can either leave it for the new owner (and remove your account access) or discuss with your installer the possibility of relocating it, where practical and permitted.

Yes. Many properties have multiple geysers (for example, main house + flatlet, or separate units in a small complex). You can install multiple controllers, each managing its own geyser or solar system.
The app can manage and display multiple devices under the same account, allowing you to monitor and control each installation individually. This is particularly useful for landlords, guesthouse owners, or anyone managing more than one geyser system on site.

Power surges and lightning can potentially damage any electronic equipment, including controllers, inverters, and household appliances.
To reduce risk:
Ensure your electrical installation includes proper surge protection devices (SPDs).
Use quality earthing and lightning protection where required.
Follow your insurer's guidelines for protecting electronic equipment.
While the controller includes some protection, severe surges or direct lightning strikes can still cause damage. Such damage is usually treated as an insurance matter rather than a warranty issue, so we recommend checking your home insurance coverage.

Yes. The controller is designed to resume its last known schedules and settings after a power failure or reboot.
When power returns:
The device performs a brief startup sequence.
Previously configured timers, temperatures, and safety settings are reloaded.
Normal operation resumes without the need for manual intervention in most cases.
If you notice unusual behaviour after repeated power outages, you can contact support for assistance in reviewing your configuration and logs.

Integration options depend on the specific firmware and ecosystem support available at the time. In many cases, basic integration is possible via:
API access and cloud-to-cloud integrations.
Energy dashboards and monitoring platforms.
In some setups, advanced users or integrators may connect the controller data to broader home automation systems. For the latest information on integrations and supported platforms, please contact Energy Sense or refer to our documentation and release notes.

Security is an important part of the system design. We implement industry-standard practices such as:
Secure communication between the controller, cloud, and app where applicable.
User authentication and account protection for remote access.
Regular updates and patches to address emerging security concerns.
As with all connected devices, we recommend using strong, unique passwords for your accounts and keeping your network and router firmware up to date to maintain overall security at home or in your business.

Yes. The controllers are often used in complexes, apartment buildings, and townhouse developments where each unit has its own geyser or solar system.
Benefits include:
Better visibility and control over individual geyser usage.
Potential for bulk installation and support agreements.
Centralised or delegated access where needed (for example, caretakers and owners).
If you are considering a multi-unit rollout, please contact us to discuss design considerations, network planning, and support options tailored to your site.

After installation, commissioning usually includes:
Verifying all electrical and hydraulic connections.
Filling and bleeding the system (for solar installations).
Confirming correct sensor readings.
Setting initial timers and temperature limits.
Testing heating and pump operation.
Connecting the controller to WiFi and linking it to your app account.
Your installer or commissioning technician will walk through these steps and confirm that everything is working as expected before handing over the system to you.

If you notice unusual behaviour, error messages, or a lack of hot water, you can:
Check your app for status and error notifications.
Verify that power is available and that the geyser isolator is on.
Review your schedules and temperature settings.
If the issue persists, contact your installer or the Energy Sense support team with:
Controller type (GCU or SGCU).
Installation date and installer details.
Photos and a description of the problem.
This information helps us or your installer diagnose the issue quickly and recommend the right fix.

Depending on the firmware version and platform support, some systems allow data export or integration with external dashboards.
This can be useful for:
Energy audits and reports.
Tracking performance improvements over time.
Sharing data with installers or consultants.
For up-to-date information about data export and integration options, please contact Energy Sense or consult the latest documentation for your controller version.

Before calling in outside help, you can:
Check the app for any errors or warnings.
Confirm that power is available and the isolator is on.
Verify that timers and temperature settings are correct.
Look for visible signs of leaks or damage around the geyser and pipework (without opening any panels or touching live parts).
Gather relevant information (photos, app screenshots, descriptions of symptoms).
This preparation helps your electrician or plumber quickly identify and resolve the issue, saving time and costs. If needed, you can also contact Energy Sense support for guidance.