Application Examples
Key for Wiring Diagram 11
eddi
device
Mains supply (230V AC from B16 circuit breaker or
13A fused spur)
Hot water cylinder
Heating element (max. 3.7kW)
Isolator (20A double pole)
Relay & Sensor Board (optional add-on for
eddi
)
Temperature probe (type PT1000) (optional)
Heat Pump (with immersion heater output)
Heat pump immersion heater relay
Functional Description
Most heat pumps require control of the immersion heater in the hot water cylinder, this is to periodically heat the water to
a higher temperature in order to kill any Legionella bacteria that may have built up in the stored water. This application
enables the heat pump to effectively control the immersion heater when required whilst the heater is actually connected
only to the
eddi
.
eddi
uses the Grid Sensor to monitor any surplus power that would otherwise be exported to the gird and diverts the same
amount of power to the heater loads, thereby reducing the surplus power down to zero.
It is not permissible to 'back-feed' the
eddi
device (i.e. a voltage supply must not be connected to the heater outputs).
Because of this, the heat pump immersion heater relay (9) needs to be connected to the eSense input of the Relay & Sensor
Board (6) instead of the immersion heater element (4). In this application, the
eddi
is configured to respond to the eSense
signal by fully switching on Heater 1 output regardless of available surplus.
Installation of the temperature probe (7) is optional; the heaters' mechanical thermostat can be used instead if water
temperature reading is not required.
Settings Required
Menu Option
Settings
Main Menu
Settings…
Display…
Icons…
Heater 1:
Top Immersion /
Bottom Immersion
Heater 2:
None
Advanced Menu…
Relays &
Sensors…
Temperatures…
PT1 Set Point:
Set Temperature as
required if using
temperature probe
eSense Input…
Boost…
Heater 1
operation and installation manual
eddi
53
1
2
3
4
5
6
7
8
9