The electric heating method is no longer on the rise. Other heating systems now dethrone it. Wood is one of them.
But we often think that, as soon as we want to heat with wood, we no longer need electricity.
This is indeed the case with the classic wood stove. But some systems that use wood for heat require an electrical supply.
This electricity requirement is related to ventilation or management of the fuel supply.
Here is an article that will address this subject, within particular the electrical connection of the pellet stove, chimney vents or even the wood boiler.
Connecting the pellet stove:
The pellet stove, in the majority of cases, is equipped with a system which allows the management of the pellet feed.
There is a mechanical and electrical system that manages an endless screw. Pellet stoves can be fitted with a programming manager that allows the fire to be turned on and off at the desired times.
Ventilation for the fireplace or for the chimney:
Fireplaces and chimneys are sometimes equipped with ventilation systems.
There are also heat exchangers that allow heat to be recovered from the exhaust duct to send heat through pipes to heat other rooms.
These different elements must be connected to a power supply to operate.
The wood-fired boiler is a device that transmits the calories produced by the combustion of wood to a heat transfer liquid, itself conveyed in a heating system (on the floor, on the ceiling or visible on the wall).
This system is identical in principle to gas or oil boilers.
There are several sub-systems (circulator, regulation) which require a general electrical supply to the boiler.
When you have to make a connection and refer to this standard, you have to ask yourself two questions:
- Is the circuit considered a specialized electrical circuit? The answer to this question conditions the connection in the electrical panel with a dedicated circuit breaker.
- What is the electrical power requirement of the supplied equipment? This other indication conditions the circuit breaker rating and the section of the electrical wire associated with the electrical connection.
Regarding the various connections linked to wood heating, the standard indicates that the circuits of the “boiler and its auxiliaries” must benefit from specialized electrical lines.
But these are nevertheless circuits which require a dedicated connection because they must be independent of the other circuits sockets and lights.
Here are general rules to be adapted on a case-by-case basis, also referring to the recommendations of the device manufacturers if they exist:
- Chimney ventilation: 2A circuit breaker, wire section 1.5mm2.
- Wood-fired boiler: 16A circuit breaker, wire section 1.5mm2.
- Woodstove: 16A circuit breaker, wire section 1.5mm2.
It is important to refer to these instructions since very often, the indications in the manufacturer’s instructions are very light on this side.
Extract from a manufacturer’s manual which describes the electrical connection of a pellet stove
Pellet stove and wood boiler:
In the following configuration, the pellet stove and the wood boiler are protected by a 16A circuit breaker.
An electrical outlet materializes the electrical connection point. A cable outlet can also be used.
The pellet stove or the wood boiler requires an electrical supply with upstream protection of 16A.
Installation without upsetting the electrical panel:
The addition of a wood heating system requiring an electric power supply sometimes intervenes after the construction of the house. The electrical panel is then already in place.
In order not to upset the organization of this switchboard or because this switchboard is too old and requires complete renovation, the solution consists in creating a small panel next to it with differential protection and the circuit breaker dedicated to the pellet stove, to the boiler electric or ventilation. Sometimes it takes less work and makes it possible to secure at least this new electrical circuit.
A small panel with a few modules can be added next to the main panel to make the electrical connection of the pellet stove or the wood boiler.
Consider continuity of service by isolating from other parts of the electrical installation:
When designing an electrical installation, you have to think about the continuity of service.
By that, I mean that some circuits must be given priority over others.
A lighting circuit, if it is momentarily unavailable for a few hours, this is not a problem.
A fault in the freezer for a whole day or a wood stove that does not light, it is a little more annoying. Dedicated devices must therefore be assigned to these circuits.
This is, of course, not an obligation. The wood heating circuit protection circuit breaker can be protected by a 30mA differential switch which protects other electrical circuits.
This is what I indicated in the previous electrical diagrams.
I find it a shame to install a wood-heating system which requires an electrical supply. Indeed, through wood heating, we often think of “energy autonomy”. By that, I mean that in the event of an electrical power cut, it is possible to heat up.
But anyway, you have to understand this need before installation. Because too often, I see electrical connections that have been made hastily to power a pellet stove or a wood boiler.