AION EMS Zeus can turn your Heat Pump from a simple power measurement into a detailed part of your home energy system.
Depending on the measurements available in Home Assistant, Zeus can monitor electrical consumption, thermal generation, COP, compressor operation, temperatures, heating circuits, source circuits and Domestic Hot Water (DHW).
Zeus uses a manufacturer-independent Heat Pump model. The current architecture has been validated with Buderus/Bosch using EMS-ESP and Viessmann Vitocal systems.
You do not need every possible sensor. Configure the measurements your Heat Pump provides, and Zeus will use the intelligence that your available data supports.
Before You Start
Your Heat Pump should already be connected to Home Assistant through its normal integration.
Before configuring Zeus, check that the relevant entities are visible in:
Home Assistant → Developer Tools → States
Depending on your Heat Pump, you may find entities for:
- Electrical Power
- Electrical Energy
- Thermal Power
- Thermal Energy
- COP
- Compressor State
- Compressor Speed / Modulation
- Flow Temperature
- Return Temperature
- Heating Circuit
- Source / Brine Circuit
- Domestic Hot Water
- Pump Speeds
Entity names vary significantly between manufacturers and integrations. Do not copy entity IDs from another installation simply because the Heat Pump model is similar.
Step 1 — Add the Heat Pump
Open:
AION EMS Zeus → Device Manager → Add Device
Choose:
Heat Pump
Give the device a clear name, for example:
Heat Pump
Buderus WLW186i
Vitocal 333G
Start with the basic Heat Pump measurements before opening the Advanced Mappings.
Step 2 — Electrical Consumption
The electrical measurement tells Zeus how much electricity the Heat Pump consumes.
Power
Select the entity representing the Heat Pump’s current electrical input power.
This should normally be a sensor measured in:
W or kW
For example, when the compressor is running, it might report:
850 W
This is consumption, not produced heat.
Energy
If available, select the accumulated electrical-energy sensor.
This will normally use:
Wh or kWh
and commonly has:
device_class: energy
state_class: total_increasing
This allows Zeus to use the Heat Pump in historical energy statistics.
Step 3 — Thermal Generation
This is one of the most important distinctions in Heat Pump configuration.
Thermal Power is not electrical consumption.
Thermal Power represents the heat currently being produced by the Heat Pump.
For example:
Electrical Consumption: 700 W
Thermal Generation: 2.80 kW
These two measurements allow Zeus to understand the relationship between electricity consumed and useful heat produced.
Thermal Power
Select the entity representing instantaneous produced heat.
Expected units:
W or kW
Thermal Energy
If your system provides accumulated produced heat, select it as Thermal Energy.
Expected units:
Wh or kWh
Do not place an electrical-consumption sensor in a Thermal field.
Step 4 — COP
COP — Coefficient of Performance — describes the relationship between thermal output and electrical input.
For example:
700 W electrical input
2.80 kW thermal output
gives approximately:
COP 4.0
If your Heat Pump provides a reliable direct COP entity, you can map it.
If electrical and thermal power measurements are available, Zeus can also use those measurements as evidence for Heat Pump Intelligence.
When sufficient evidence is unavailable, Zeus will show Unavailable rather than inventing a COP value.
Step 5 — Compressor Information
If your integration provides compressor information, configure the available entities.
Useful measurements include:
Compressor State
Running / stopped information.
Compressor Speed / Modulation
How strongly the compressor is currently operating.
Target Compressor Speed
Where supported by the Heat Pump.
These measurements help Zeus distinguish between:
Running · Standby · Inactive
and provide better operating and cycle intelligence.
Advanced Heat Pump Mappings
Once the basic Heat Pump is working, open:
Device Manager → Heat Pump → Edit → Advanced Mappings
These fields provide deeper Heat Pump Intelligence.
You only need to configure measurements actually available from your system.
Heat Carrier / Heating Circuit
The heating circuit describes the water carrying heat from the Heat Pump into the building.
Where available, configure:
Flow / Supply Temperature
Temperature leaving the Heat Pump toward the heating system.
Return Temperature
Temperature returning from the heating system.
Heating Circuit / Secondary Pump Speed
Speed or modulation of the heating-circuit pump.
These measurements help Zeus understand the thermal behavior of the heating circuit.
Source / Brine Circuit
Ground-source and some other Heat Pumps provide information about the energy-source circuit.
Depending on the system this may be called:
Brine · Source · Primary Circuit
Available measurements can include:
Source Inlet Temperature
Source Outlet Temperature
Source / Primary Pump Speed
These fields are optional.
Air-source Heat Pumps may not provide equivalent measurements, and that is perfectly normal.
Space Heating and Domestic Hot Water
Some Heat Pumps provide separate measurements for:
Space Heating
and
Domestic Hot Water (DHW)
If your system provides these measurements, enable:
Separate Heating / DHW measurements available
Zeus will then allow the two circuits to be configured independently.
Space Heating
Where available, configure:
Heating Electrical Power
Current electrical consumption used for space heating.
Heating Thermal Power
Current heat generation for space heating.
Heating Electrical Energy
Accumulated electrical consumption for space heating.
Heating Thermal Energy
Accumulated heat produced for space heating.
It is completely acceptable if your system provides only the Energy measurements and not separate live Power measurements.
Domestic Hot Water — Heat Pump
The Heat Pump may also provide separate measurements for heating domestic hot water.
Where available, configure:
DHW Electrical Power
Current electrical consumption during DHW production.
DHW Thermal Power
Current thermal production for DHW.
DHW Electrical Energy
Accumulated electricity consumed for DHW.
DHW Thermal Energy
Accumulated heat produced for DHW.
DHW Temperature
Current domestic-hot-water temperature.
Zeus keeps these measurements clearly separated from Space Heating.
Important — Heat Pump DHW vs Separate Water Heater
A Heat Pump producing Domestic Hot Water and a separate electric water heater are not the same device.
For example, if your installation has:
Heat Pump → DHW production
and
my-PV AC ELWA 2 → additional water heating
register the ELWA separately as a Water Heater.
Zeus can then distinguish how much energy comes from the Heat Pump and how much comes from the independent water heater.
Legacy Mappings
Older Zeus installations may contain:
Legacy Heating Energy
Legacy DHW Energy
Legacy Cooling Energy
These fields exist for backward compatibility.
Older Zeus versions could not reliably determine whether these measurements represented electrical consumption or thermal generation, so Zeus intentionally does not guess.
If you have correctly moved these measurements into the new classified Heating/DHW fields, the corresponding legacy mappings can be left empty.
For a new installation, do not use Legacy Mappings unless specifically required.
Cooling
If your Heat Pump also provides active cooling measurements, enable:
Cooling measurements available
Then configure the available Cooling Power/Energy measurements.
If your Heat Pump does not provide cooling, leave this disabled. Zeus will hide the unused Cooling information.
Step 6 — Save and Verify
Click:
Update Device
Then reopen the Heat Pump editor once.
Check that the selected entities remain saved.
Next open:
Zeus → Statistics → Heat Pump
Depending on your configuration, you should see information such as:
Electrical Consumption
Thermal Generation
Operating State
COP
Compressor Activity
Heating Circuit
DHW Consumption & Generation
Step 7 — Verify the Command Center
Open the Command Center while the Heat Pump is operating.
Compare Zeus with the original Home Assistant entities.
For example:
Home Assistant electrical power: 700 W
Zeus Consumption: approximately 700 W
Home Assistant thermal output: 2.30 kW
Zeus Production: approximately 2.30 kW
Small temporary differences can occur because entities update at different times.
If separate DHW measurements are configured, Zeus can also display a dedicated:
DHW · HEAT PUMP
section.
Validated Heat Pump Systems
The manufacturer-independent Heat Pump architecture has currently been real-world validated with:
Buderus / Bosch — EMS-ESP
Including electrical consumption, thermal generation, compressor evidence, Heat Carrier circuit, Source/Brine circuit and separate Heating/DHW measurements.
Viessmann — Vitocal
Including electrical and thermal measurements, Heating/DHW separation, primary/secondary circuit evidence and Secondary Pump Speed.
Support is not limited to these manufacturers. Other Heat Pumps can use the Generic Heat Pump mappings when the required measurements are available in Home Assistant.
What If Some Measurements Are Missing?
That is normal.
Heat Pump integrations vary enormously in the information they expose.
Zeus is designed to degrade gracefully:
Electrical data only → consumption monitoring
Electrical + thermal data → production and COP intelligence
Compressor data → operating/cycle intelligence
Heating/DHW data → circuit-level analysis
Temperature/pump data → advanced thermal evidence
You do not need to fill every field.
Never choose an unrelated entity simply to remove an “Unavailable” value. Accurate incomplete data is better than incorrect complete data.
Heat Pump Connected
Once the live Consumption, Production and operating state match your real Heat Pump, the basic configuration is complete.
You can always return to Device Manager later as additional measurements become available.
Next: Connect Your Water Heating
Measure electricity. Measure heat. Let Zeus understand the difference.