eddiApplication Examples

  1. Intro
  2. Single Element Water Heater
  3. Dual Element Water Heater
  4. Economy Tariff with Dual Rate Meter
  5. Economy Tariff with Separate Meters (Heater 1)
  6. Economy Tariff with Separate Meters (Heater 2)
  7. Radiator and Water Heating
  8. Underfloor Heating Mat and Water Heating
  9. Water Heater with De-stratification Pump
  10. Water Heater with Auxiliary Boiler Control - Y Plan
  11. Water Heater with Auxiliary Boiler Control - S Plan
  12. Heat Pump with Water Heating
  13. Heat Pump with Water Heating and Buffer Tank
  14. Heat Pump with Water Heating and Priority Control
  15. Pool and Water Heating

1. Intro

The following wiring diagrams show some suggested applications and are examples only; there are many more possibilities.

Please refer to the Safety Section and be sure to read all of the installation sections before attempting to install the eddi.

A good level of electrical competence and a reasonable understanding of domestic plumbing systems is assumed for studying these application examples.

Contact technical support if in any doubt: support@myenergi.uk

2. Single Element Water Heater

 

Key for Wiring Diagram 1

 

eddi device
Mains supply (230V AC from B16 circuit breaker or 13A fused spur)
Hot water cylinder
Heating element 1 (max. 3.7kW)
Isolator (20A double pole)
Auxiliary water heating boiler

 

Functional Description

This is the most simple installation and the most common.

A single heater is wired to the Heater 1 output.

The water in the cylinder is heated with only surplus power until the thermostat has opened, the eddi will display Max Temp Reached and the surplus power will then be exported until the water cools, heating will then resume.

An auxiliary heat source (e.g. a gas boiler) is set to heat the water either early in the morning or later in the evening, depending on the home owners’ lifestyle. Heating the water during times of generation (e.g. daylight hours) is best avoided to allow maximum capacity for the surplus energy.

This is the default configuration for eddi; the settings do not need to be altered for this application.

Settings Required

 

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Water Top/Water Bottom
Heater 2: None
Priority Heater 1

 

3. Dual Element Water Heater

 

Key for Wiring Diagram 2

 

eddi device
Mains supply (230V AC from B16 circuit breaker or 13A fused spur)
Hot water cylinder
Heating element 1 (max. 3.7kW)
Isolator (20A double pole)
Heating element 2 (max. 3.7kW)

 

Functional Description

Electric only households tend to have a hot water cylinder with two immersion heaters, this is perfect for eddi as it can support heating two heaters sequentially.

Heater 1 (the top immersion heater) is heated with surplus power until the water at the top of the cylinder is hot and the thermostat opens, then eddi will immediately switch over to Heater 2 ; heating the bottom of the cylinder. This makes the most of surplus energy as sometimes there will not be enough to heat the whole volume of the cylinder; it’s best to heat a smaller proportion (i.e. the top) first so there is some usable hot water, rather than a larger volume of warm water.

During heating of the lower priority heater (Heater 2), eddi will switch back to the higher priority heater (Heater 1) every 15 mins to check if it can store any more heat.

When the water is fully heated, any surplus power will be exported, eddi will switch back to the priority heater and check the lower priority heater every 15 mins.

The heating priority can be changed in the Main Menu (Priority).

Settings Required

 

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Water Top
Heater 2: Water Bottom
Priority Heater 1

 

4. Economy Tariff with Dual Rate Meter

 

Key for Wiring Diagram 3

 

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)
Economy rate electric sense wiring (live only when economy rate is available)

 

Functional Description

It is common for electric only households to employ dual tariff billing. This application enables automatic heating of water when the economy tariff is available whilst also using any surplus generated power to heat the water.

The economy rate electricity can be time based or random, in either case, eddi can be set to heat the water at the economy rate whenever possible, or at the economy rate only during certain times.

Heater 1 (the top immersion heater) is heated with surplus power until the water at the top of the cylinder is hot and the thermostat opens, then eddi will immediately switch over to Heater 2 ; heating the bottom of the cylinder. This makes the most of surplus energy as sometimes there will not be enough to heat the whole volume of the cylinder; it’s best to heat a smaller proportion (i.e. the top) first so there is some usable hot water, rather than a larger volume of warm water.

During heating of Heater 2, eddi will switch back to Heater 1 every 15 minutes to check if it can store any more heat.

When the water is fully heated, any surplus power will be exported, eddi will switch back to the priority heater and check the lower priority heater every 15 minutes.

If eSense Input is set to Boost Enable 1&2, the BOOST TIMER screen for either heater will include an option to enable the boost timer only when the eSense input is live. In the BOOST TIMER, the e can be toggled on/off, if e is present, the boost will activate only when the boost times are valid and the economy rate tariff is available.

Alternatively the eSense input can be used to activate the boost whenever the economy tariff rate electricity is available, regardless of boost times. To do this, eSense Input should be set to Boost 1&2. When using this option, the Boost Timer is not needed.

If automatic sensing of economy rate times is not needed, the boost timer can be simply set to coincide with the economy tariff times. In this case the Relay & Sensor Board and the eSense wiring are not required.

Installation of the temperature probes is optional; the heaters’ mechanical thermostat is used by eddi if temperature readings are not required.
The eddi device should be labelled with a “dual supply” warning.

Settings Required

 

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Top Immersion
Heater 2: Bottom Immersion
Priority Heater 1
Advanced Menu Relays & Sensors Temperatures Set Temperatures as required if using temperature probes
eSense Input Boost Boost Enable 1&2/Boost 1&2

 

5. Economy Tariff with Separate Meters (Heater 1)

 

Key for Wiring Diagram 4

 

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)
Mains supply (off-peak timed) (230V AC from B16 circuit breaker or 13A fused spur)

 

Functional Description

Some electric only households that employ dual tariff billing use two separate electricity meters; one is live for 24 hours and the other is off-peak timed and bills at the economy rate. Only some appliances are connected to the off-peak supply (usually water heaters and storage heaters).

This application enables automatic boosting of water heating when the economy tariff is available whilst also using any surplus generated power to heat the water. Both the top and bottom immersion heaters can use surplus power and be boosted with peak rate electricity. However, only Heater 1 can be boosted with off-peak electricity (See page 44 if it is desired to have Heater 2 boost using off-peak power).

eddi is powered from the 24-hour supply and the bottom immersion heater is wired directly to Heater 2 output. During the economy tariff times, power needs to be drawn from the off-peak tariff meter, to achieve this the top immersion heater is switched from the eddi Heater 1 output and the off-peak supply using both relays of the Relay & Sensor Board .

Heater 1 (the top immersion heater) is heated with surplus power until the water at the top of the cylinder is hot and the thermostat opens, then eddi will immediately switch over to Heater 2; heating the bottom of the cylinder. This makes the most of surplus energy as sometimes there will not be enough to heat the whole volume of the cylinder; it’s best to heat a smaller proportion (i.e. the top) first so there is some usable hot water, rather than a larger volume of warm water.

During heating of Heater 2, eddi will switch back to Heater 1 every 15 minutes to check if it can store any more heat.

When the water is fully heated, any surplus power will be exported, eddi will switch back to the priority heater and check the lower priority heater every 15 minutes.

If eSense Input is set to Boost Enable 1, the BOOST TIMER screen for Heater 1 will include an option to enable the boost timer only when the eSense input is live. In the BOOST TIMER, the e can be toggled on/off, if e is present, the boost will activate only when the boost times are valid and the economy rate tariff is available.

Alternatively the eSense input can be used to activate the boost whenever the economy tariff rate electricity is available, regardless of boost times. To do this, eSense Input should be set to Boost 1. When using this option, the Boost Timer is not needed.

Installation of the temperature probes is optional; the heaters’ mechanical thermostat is used by eddi if temperature readings are not required.

The eddi device should be labelled with a “dual supply” warning.

Settings Required

 

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Top Immersion
Heater 2: Bottom Immersion
Priority Heater 1
Advanced Menu Relays & Sensors Temperatures Set Temperatures as required if using temperature probes
eSense Input Boost Boost Enable 1/Boost 1

 

6. Economy Tariff with Separate Meters (Heater 2)

 

Key for Wiring Diagram 5

 

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)
Mains supply (off-peak timed) (230V AC from B16 circuit breaker or 13A fused spur)

 

Functional Description

Some electric only households that employ dual tariff billing use two separate electricity meters; one is live for 24 hours and the other is off-peak timed and bills at the economy rate. Only some appliances are connected to the off-peak supply (usually water heaters and storage heaters).

This application enables automatic boosting of water heating when the economy tariff is available whilst also using any surplus generated power to heat the water. Both the top and bottom immersion heaters can use surplus power and be boosted with peak rate electricity. However, only Heater 2 can be boosted with off-peak electricity (See page 42 if it is desired to have Heater 1 boost using off-peak power).

eddi is powered from the 24-hour supply and the bottom immersion heater is wired directly to Heater 1 output. During the economy tariff times, power needs to be drawn from the off-peak tariff meter, to achieve this the top immersion heater is switched from the eddi Heater 2 output and the off-peak supply using both relays of the Relay & Sensor Board .

Heater 1 (the top immersion heater) is heated with surplus power until the water at the top of the cylinder is hot and the thermostat opens, then eddi will immediately switch over to Heater 2; heating the bottom of the cylinder. This makes the most of surplus energy as sometimes there will not be enough to heat the whole volume of the cylinder; it’s best to heat a smaller proportion (i.e. the top) first so there is some usable hot water, rather than a larger volume of warm water.

During heating of Heater 2, eddi will switch back to Heater 1 every 15 minutes to check if it can store any more heat.

When the water is fully heated, any surplus power will be exported, eddi will switch back to the priority heater and check the lower priority heater every 15 minutes.

If eSense Input is set to Boost Enable 2, the BOOST TIMER screen for Heater 2 will include an option to enable the boost timer only when the eSense input is live. In the BOOST TIMER, the e can be toggled on/off, if e is present, the boost will activate only when the boost times are valid and the economy rate tariff is available.

Alternatively the eSense input can be used to activate the boost whenever the economy tariff rate electricity is available, regardless of boost times. To do this, eSense Input should be set to Boost 2. When using this option, the Boost Timer is not needed.

Installation of the temperature probes is optional; the heaters’ mechanical thermostat is used by eddi if temperature readings are not required.

The eddi device should be labelled with a “dual supply” warning.

Settings Required

 

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Top Immersion
Heater 2: Bottom Immersion
Priority Heater 1
Advanced Menu Relays & Sensors Temperatures Set Temperatures as required if using temperature probes
eSense Input Boost Boost Enable 2/Boost 2

 

7. Radiator and Water Heating

 

Key for Wiring Diagram 6

 

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)
Electric radiator (150W min. 3.7kW max.)

 

Functional Description

To maximise self-consumption of surplus power, an electric radiator can be heated once the hot water cylinder is up-to temperature, eddi can support heating two heaters sequentially and so is perfect for this application.

Heater 1 (the immersion heater in the hot water cylinder) is heated with surplus power until the water is hot and the thermostat opens, then eddi will immediately switch over to Heater 2 to heat the radiator with surplus power.

During heating of the lower priority heater (Heater 2), eddi will switch back to the higher priority heater (Heater 1) every 15 mins to check if it can store any more heat.

The heating priority can be changed in the Main Menu (Priority).

Settings Required

 

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Top Immersion / Bottom Immersion
Heater 2: Radiator
Priority Heater 1

 

8. Underfloor Heating Mat and Water Heating

Key for Wiring Diagram 7

 

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)
Mains supply for underfloor heating controller
Underfloor heating mat (max. 3.7kW)
Underfloor heating controller or thermostat

 

Functional Description

As well as water heating, eddi can be used with electric underfloor heating mats. In this application the water is heated as priority and when fully heated, the surplus power is instead diverted to the underfloor heating mat.

Heater 1 (the immersion heater in the hot water cylinder) is heated with surplus power until the water is hot and the thermostat opens, then eddi will immediately switch over to Heater 2 (the underfloor heating mat) and continue diverting the surplus power.

During heating of the lower priority heater (Heater 2), eddi will switch back to the higher priority heater (Heater 1) every 15 mins to check if it can store any more heat.
The heating priority can be changed in the Main Menu (Priority).

The underfloor heating controller or thermostat is wired to the eSense input of the Relay & Sensor Board . The eSense Input setting is set to Heater Enable 2 so only when the thermostat is calling for heat will eddi apply power to the mat. When the underfloor heating thermostat is open eddi will display Max Temp Reached.

Installation of the temperature probe is optional; the immersion heaters’ mechanical thermostat is used by eddi 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: Underfloor
Priority Heater 1
Advanced Menu Relays & Sensors Temperatures Set Temperatures as required if using temperature probes
eSense Input Heater Enable Heater 2

 

9. Water Heater with De-stratification Pump

Key for Wiring Diagram 8

 

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)
De-stratification pump
Switched fused spur for pump (5A)

 

Functional Description

Hot water cylinders that are normally heated by a gas or oil boiler often have an immersion heater installed in the top half of the cylinder. This means only about half of the water can be heated with electric. With the addition of a de-stratification pump, almost the entire volume of the hot water cylinder can be fully heated.

The water in the cylinder is heated via the immersion heater with surplus power until the thermostat has opened, then eddi will run the pump for up to five minutes. This pushes some of the hot water from the top of the cylinder , down to the bottom, thus pulling the cooler water up to the region that can be heated via the immersion heater . As the cooler water is drawn up, the thermostat will close again and eddi is able to resume heating the water.

An auxiliary heat source (e.g. a gas boiler) is set to heat the water either early in the morning or later in the evening, depending on the home owners’ lifestyle. Heating the water during times of generation (e.g. daylight hours) is best avoided to allow maximum capacity for the surplus energy.

Installation of the temperature probes is optional; the immersion heaters’ mechanical thermostat is used by eddi if water temperature reading is not required.

Settings Required

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Top Immersion
Heater 2: None
Advanced Menu Relay & Sensors Relay 1 Heating Destrat 1

 

10. Water Heater with Auxiliary Boiler Control - Y Plan

Key for Wiring Diagram 9

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)
Y-Plan wiring centre
Auxiliary water heating boiler

 

Functional Description

As eddi is predominately a water heating control device, it can be used to manage all of the water heating, even if an auxiliary heat source is used to heat the water. With this application the homeowner will be able to program auxiliary boiler boost times with eddi.

In the UK a popular plumbing and wiring scheme used by central heating systems is referred to as ‘Y-Plan’. This scheme has a standard junction box which eddi can be wired to, to enable programming of water heating times with the BOOST TIMER feature of the eddi.

The water heating element is wired to the Heater 1 output and Relay 1 of the Relay & Sensor Board is wired to the Y-Plan wiring centre . Any existing water heating control is removed or disconnected.

The water in the cylinder is heated with only surplus power until the thermostat has opened, the eddi will display Max Temp Reached and the surplus power will then be exported until the water cools, heating will then resume.

The BOOST TIMER (RELAY 1) in the eddi is used to program the auxiliary heat source (e.g. a gas boiler) to heat the water either early in the morning or later in the evening, depending on the home owners’ lifestyle. Heating the water during times of generation (e.g. daylight hours) is best avoided to allow maximum capacity for the surplus energy.

Whenever the boost is active, Relay 1 will operate and the Y-plan heating system will respond, heating the water via the auxiliary boiler.
The BOOST TIMER (HEATER 1) can be used if it is desired to boost water heating with the immersion heater.

Installation of the temperature probe is optional; the immersion heaters’ mechanical thermostat is used by eddi if water temperature reading is not required.

Settings Required

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Water Top
Heater 2: None
Advanced Menu Relay & Sensors Temperatures Set Temperatures as required if using temperature probes
Relay 1 Boost Timer

 

11. Water Heater with Auxiliary Boiler Control - S Plan

Key for Wiring Diagram 10

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)
S-Plan wiring centre
Auxiliary water heating boiler

 

Functional Description

As eddi is predominately a water heating control device, it can be used to manage all of the water heating, even if an auxiliary heat source is used to heat the water. With this application the homeowner will be able to program auxiliary boiler boost times with eddi.

In the UK a popular plumbing and wiring scheme used by central heating systems is referred to as ‘S-Plan’. This scheme usually has a standard junction box which eddi can be wired to, to enable programming of water heating times with the BOOST TIMER feature of the eddi.

The water heating element is wired to the Heater 1 output and Relay 1 of the Relay & Sensor Board is wired to the S-Plan wiring centre . Any existing water heating control is removed or disconnected.

The water in the cylinder is heated with only surplus power until the thermostat has opened, the eddi will display Max Temp Reached and the surplus power will then be exported until the water cools, heating will then resume.

The BOOST TIMER (RELAY 1) in the eddi is used to program the auxiliary heat source (e.g. a gas boiler) to heat the water either early in the morning or later in the evening, depending on the home owners’ lifestyle. Heating the water during times of generation (e.g. daylight hours) is best avoided to allow maximum capacity for the surplus energy.

Whenever the boost is active, Relay 1 will operate and the S-plan heating system will respond, heating the water via the auxiliary boiler.

The BOOST TIMER (HEATER 1) can be used if it is desired to boost water heating with the immersion heater.

Installation of the temperature probe is optional; the immersion heaters’ mechanical thermostat is used by eddi if water temperature reading is not required.

Settings Required

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Water Top
Heater 2: None
Advanced Menu Relay & Sensors Temperatures Set Temperatures as required if using temperature probes
Relay 1 Boost Timer

 

12. Heat Pump with Water Heating

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 grid 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 needs to be connected to the eSense input of the Relay & Sensor Board instead of the immersion heater element . 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 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 Relay & Sensors Temperatures PT1 Set Point: Set Temperatures as required if using temperature probes
eSense Input Boost Heater 1

 

13. Heat Pump with Water Heating and Buffer Tank

Key for Wiring Diagram 12

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
Buffer cylinder
Heating element 2 (max. 3.7kW)

 

Functional Description

Some heat pump heating systems have a buffer tank for the heating circuit as well as a hot water cylinder.

eddi can be used to make good use of any surplus generation by fully heating the water first and then heating the buffer, allowing the maximum amount of surplus energy to be stored.

eddi uses the Grid Sensor to monitor any surplus power that would otherwise be exported to the grid and diverts the same amount of power to the heater loads, thereby reducing the surplus power down to zero.

For this application two heating elements are wired to the eddi; the water immersion heater is connected to Heater 1 output and the buffer tank immersion heater is connected to Heater 2 output. Priority is given to the water heating and only when fully heated does the eddi switch to heating the buffer tank.

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. Remember it is not permissible to ‘back-feed’ the eddi device; a voltage supply must not be connected to the heater outputs. Because of this, the heat pump immersion heater relay needs to be connected to the eSense input of the Relay & Sensor Board instead of the immersion heater element . 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 probes is optional; the heaters’ mechanical thermostat can be used instead if temperature readings are not required.

Settings Required

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Top Immersion / Bottom Immersion
Heater 2: Radiator / Underfloor Heating
Priority Heater 1
Advanced Menu Relay & Sensors Temperatures Set Temperatures as required if using temperature probes
eSense Input Boost Boost 1

 

14. Heat Pump with Water Heating and Priority Control

Key for Wiring Diagram 13

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
Heat pump hot water timer

 

Functional Description

In this application the water is heated by eddi with the immersion heater when there is a relativity small amount of surplus power (e.g. < 1kW). But when there is enough surplus the heat pump is used to heat the water instead. This configuration takes advantage of the higher efficiency of the heat pump compared with the immersion heater, whilst ensuring no surplus power is wasted.

For this application the water heating element is wired to the eddi Heater 1 output. The water heating timer control for the heat pump is connected to the Relay 1 normally open contacts of the Relay & Sensor Board .

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. Remember it is not permissible to ‘back-feed’ the eddi device; a voltage supply must not be connected to the heater outputs. Because of this, the heat pump immersion heater relay needs to be connected to the eSense input of the Relay & Sensor Board instead of the immersion heater element . 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 is optional; the heaters’ mechanical thermostat can be used instead if temperature reading is not required.

 

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Top Immersion
Heater 2: None
Priority Heater 1
Advanced Menu Relays & Sensors Temperatures PT1 Set Point: If PT1 temperature probe is used, set temperatures as desired for water heating e.g. 60°C
Relay 1 Export On Threshold: Should be set to power level required for efficient heap pump operation e.g. 1kW
Off Threshold: 50% of On Threshold e.g. 500W
Inc Diverted: YES
Min On Time: Set this to reduce cycling of heat pump e.g. 15m
Min Off Time Set this to reduce cycling of heat pump e.g. 5m
eSense Imput Boost Heater 1

 

15. Pool and Water Heating

Key for Wiring Diagram 14

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)
Swimming Pool
In-line electric pool heater (max. 3.7kW)
Pool heater thermostat (16A rated)
Pool circulation pump
Pool circulation pump fused spur

 

Functional Description

In properties that benefit from a swimming pool, eddi can be used to maximise self-consumption of surplus power, by first heating the domestic water before switching to divert the surplus power to contribute to pool heating.

Heater 1 (the immersion heater in the hot water cylinder) is heated with surplus power until the domestic water is hot and the thermostat opens, then eddi will immediately switch over to Heater 2 to heat the pool with surplus power.

During heating of the pool (Heater 2), eddi will briefly switch back to the domestic water heater (Heater 1) every 15 mins to check if it can store any more heat.

When Heater 2 is active (i.e. eddi is heating the pool), Relay 1 of the Relay & Sensor Board will be on and so the pool circulation pump will run thus transferring heat from the pool heater to the swimming pool.

Installation of the temperature probes is optional; the heaters’ mechanical thermostats are used by eddi if temperature readings are not required.

Settings Required

Menu Option Settings
Main Menu Settings Display Icons Heater 1: Top Immersion / Bottom Immersion
Heater 2: Pool
Priority Heater 1
Advanced Menu Relay & Sensors Temperatures Set Temperatures as required if using temperature probes
eSense Input Heating Heater 1