my-PV AC ELWA 2 - Installation Summary
What is the AC ELWA 2?
The AC ELWA 2 from my-PV is an intelligent water heating device that uses excess energy from your photovoltaic system. The AC ELWA 2 is permanently installed in your hot water tank or buffer tank and heats the water automatically when your solar system produces more electricity than you currently consume.
Important Safety Instructions for the my-PV AC ELWA 2
Caution: The AC ELWA 2 may only be installed by a qualified electrician! This is not only important for safety reasons, but also required for the AC ELWA 2 warranty. Working on electrical systems is life-threatening and should only be performed by qualified personnel.
What is included in the my-PV AC ELWA 2 delivery scope?
The AC ELWA 2 system consists of three main parts: the electronics unit with display, the heating element with integrated temperature sensor T1, and a connecting frame. The AC ELWA 2 package also includes important accessories such as an external T2 temperature sensor, a Wi-Fi antenna, various plugs and connection cables, and mounting hardware.
Installation steps for the my-PV AC ELWA 2
Preparation for AC ELWA 2 installation
Before the AC ELWA 2 can be installed, the hot water tank must be completely drained. The specialist will check whether a suitable threaded sleeve (G 1.5 inch) is available or whether the AC ELWA 2 needs to be mounted with a lock nut. The correct installation position is also important: The AC ELWA 2 is installed horizontally with the electrical connections facing downwards.
Installing the AC ELWA 2 Heating Element
The AC ELWA 2 heating element has an unheated zone of 140 mm from the sealing surface. This special feature of the AC ELWA 2 must be observed during installation. The supplied O-ring is used for sealing and must not be treated with lubricants. Particular care must be taken when screwing in the AC ELWA 2 heating element: First, screw it in gently until the seal is lightly seated. Then, tighten the AC ELWA 2 heating element with a 60 mm open-end wrench, but with a maximum torque of 50 Nm.
Installing the my-PV AC ELWA 2 Electronic Unit
First, an anti-twist screw is installed to prevent the AC ELWA 2 system from twisting later. The black connection frame is then placed on the heating element mounting ring. The electrical connections between the heating element and the AC ELWA 2 electronics unit are established – first the 3-pin temperature sensor T1, then the 6-pin heating element connection. Finally, the AC ELWA 2 electronics unit is hung in the connection frame and secured with a fastening screw.
Electrical Connections of the my-PV AC ELWA 2
Before electrically connecting the AC ELWA 2, an important protective conductor test must be performed. This ensures that the AC ELWA 2 is properly grounded. The AC ELWA 2 is connected to a 230V AC supply, with a minimum cable cross-section of 2.5 mm². The AC ELWA 2 is protected by a maximum of 16A fuse. Important: No other consumers may be connected to the same circuit as the AC ELWA 2.
Temperature sensor and other wiring of the AC ELWA 2
The AC ELWA 2's external temperature sensor T2 is connected to the 8-pin connector. This sensor is particularly important for the optimal function of the AC ELWA 2, as it monitors the water temperature in the storage tank. The further wiring of the AC ELWA 2 depends on the selected operating mode.
Operating Modes of the AC ELWA 2
The AC ELWA 2 can be operated in two different modes:
Operating Mode M1 (3.5 kW): Here, the AC ELWA 2 operates with a single heating element that is continuously controlled. This AC ELWA 2 configuration is sufficient for most households.
Operating Mode M3 (3.5 + 3 kW): In this AC ELWA 2 configuration, two heating elements are used – the integrated one is continuously controlled, and an external one is switched on. The T2 temperature sensor is mandatory for this operating mode of the AC ELWA 2.
Important information on AC ELWA 2 maintenance
The AC ELWA 2 is largely maintenance-free. However, hard water can cause calcification of the AC ELWA 2 heating element, especially if temperatures above 60°C are set. An annual inspection of the AC ELWA 2 heating element is therefore recommended. The electronics unit of the AC ELWA 2 should never be opened and can be cleaned with a damp cloth.
Conclusion on the my-PV AC ELWA 2 installation
The installation of the AC ELWA 2 requires manual skills and electrical engineering expertise. Although this guide explains the key steps for AC ELWA 2 installation, you should always commission a qualified specialist company for the actual installation. This is the only way to ensure that your AC ELWA 2 functions safely and properly, and that you can enjoy the efficient use of your solar power for a long time.
