Scheme connecting the electric boiler to 220 and 380 V

The main issue that will be considered in this article is a typical scheme for connecting an electric heating boiler to a 220 and 380-volt network. That is why the main bias will be directed only at the rules and the sequence of connecting the wires. As for the installation of radiators, piping and other elements of the central heating system, we will provide it only in general form.

Contents:

Installation options
Single-phase wiring
Wiring in three-phase network

Installation options

Connecting the input wires

So, let's first figure out the options for connecting an electric boiler in a private house and apartment with their own hands:

If the capacity of the water heater does not exceed 3.5 kW,it is powered from the socket. This allows the use of a single-phase 220V network.
In the event that the power varies between 3.5-7 kW, it is necessary to perform electrical wiring with your own hands directly from the junction box. This is due to the fact that the socket can not withstand high current loads. As in the previous case, a 220-volt network is allowed for use.
Well, the last option that can meet is an electric boiler with a capacity of over 7 kW.In this case, it is necessary not only to maintain a separate cable from the switch box, but also to use a more powerful 3-phase 380V network.

Single-phase wiring

As we have already mentioned, it is possible to connect the water heater to a single-phase network via a plug or a separately-powered cable. On the first option, even to stop there is no sense, because. Plug the plug into the socket will be able to any.

Regarding the second option, first you need to calculate the cross-section of the current( if the required diameter of the wires is not specified in the product certificate), then lead the conductor to the installation site of the boiler. Further all is simple - we connect a phase, a zero and grounding with corresponding terminals in the unit( on them the marking is indicated).To your attention the basic scheme of connecting an electric boiler with a thermostat to a heating system: 220V network

Wiring in a three-phase network

The connection scheme of an electric boiler to a three-phase network is more complicated, but even a beginner can do it.

Three phases must be connected as follows:

Three phases

Note the following nuances:

A technical data sheet is included with each heater, in which the manufacturer's recommended electrical circuit diagram is indicated. Be guided only by this document in your case, tk.far from always available on the Internet examples can be suitable for your heating system.
Be sure to protect the boiler with a circuit breaker and an RCD.These devices will prevent the unit from overloading, shorting and leakage of current in the mains.
The grounding of the wiring must be present.

We would like to draw your attention to the graphic design of electric heating in a two-storey villa using a boiler: