Product Overview
The Geyserwise MWS Controller is a solar PV water-heating controller designed to help convert a standard electric geyser into a PV-assisted hot water system. It uses MPPT technology to manage solar input from PV panels and supply controlled power to a compatible geyser element, reducing reliance on grid electricity for water heating where the system is correctly designed and installed.
Key Features
- MPPT solar control helps improve power conversion from the PV array to the geyser element.
- Supports solar PV input with a maximum input voltage of 350 VDC and maximum solar array size of 4000 W.
- Designed for use with geyser elements from 1500 W to 4000 W, with supported element resistance from 12Ω to 27Ω.
- Can operate from solar PV or 230 V AC supply, allowing for practical solar water heating with mains backup.
- RS485 communication between the display and main MWS box.
- Wi-Fi support via Tuya or Smartlife applications for connected system control.
- Includes reverse polarity protection for solar PV connections.
- IP32 enclosure ingress protection rating for suitable protected installation environments.
Applications
- PV-assisted water heating for domestic electric geysers.
- Homes looking to reduce grid electricity usage for hot water heating.
- Installations where a traditional pumped solar thermal system is less practical.
- Solar geyser conversions where the geyser and PV array can be correctly matched to the MWS controller requirements.
Why Choose This Product?
The Geyserwise MWS Controller is a practical option for homeowners and installers who want to use solar PV to heat water without adding a pumped thermal collector system. It is designed around PV input, MPPT conversion, geyser element control, and app-based connectivity, making it well suited to correctly specified South African solar water-heating installations.
Important Notes
- This product must be installed by suitably qualified persons, and an electrical COC is required.
- The PV array must be designed so that the open-circuit voltage does not exceed the controller limit of 350 VDC.
- The maximum solar panel current must be below 15 A.
- The controller is not suitable for use with PTC elements.
- PV panel selection, series configuration, geyser element resistance, irradiation level, roof structure, cable sizing, and safety requirements must be checked before installation.
- Dimensions, weight, included accessories, and warranty terms for the controller were not specified on the reviewed source page and should be confirmed before publishing if required.
Technical Specifications
| Specification |
Detail |
| Brand |
Geyserwise |
| Product Type |
MWS solar PV water-heating controller |
| Maximum Input Voltage |
350 VDC open-circuit voltage |
| Rated Input Voltage |
230 V AC, 350 V DC |
| Rated Input Current |
20 A AC, 15 A DC |
| Solar Input Voltage Range |
125 VDC to 350 VDC |
| MPPT Range |
120 V to 350 V DC |
| Maximum Input Current |
15 A |
| Maximum Solar Power Conversion |
4000 W |
| Maximum Solar Array Size |
4000 W |
| Solar Connection |
MC4 solar connectors |
| Solar Output Voltage |
40 V to 230 Vrms modulated sine wave |
| Solar Output Current |
20 A |
| AC Input |
230 V AC, 50 Hz |
| Mains AC Voltage Range |
85 V to 250 V AC |
| System Power Supply |
Solar PV or 230 V AC |
| Compatible Geyser Element Power |
1500 W to 4000 W |
| Element Resistance |
12Ω to 27Ω |
| Element Compatibility |
Not suitable for use with PTC elements |
| Thermostat |
Electronic thermostat |
| Thermostat Safety |
Electromechanical thermal cutout |
| Protection |
Reverse polarity protection for solar PV connections |
| Ingress Protection Rating |
IP32 |
| Communications |
RS485 between display and main MWS box; Wi-Fi via Tuya or Smartlife applications |
| Mounting |
MWS to be mounted vertically |
| Standards / Approvals Listed By Source |
EN / IEC 62109-1, IEC 60730-2-9, IEC 60730-1, EN / IEC 61000-6-3, EN 61000-3-12, EN / IEC 61000-3-11, EN / IEC 61000-6-1, ICASA Type Approval |
