EMS device compatibility

Electrical compatibility

The EMS interface boards and the Gateways are electrically compatible with all EMS and Heatronic 3 and 4 versions. These include EMS, EMS+, EMS2, EMS Plus, Logamatic EMS, Junkers 2-wire, Heatronic 3, 4. The EMS bus is 16V.

Only boilers, heat pumps and accessories like thermostats made by/for the Bosch group that have an EMS bus are supported. These brands include Bosch, Nefit, Buderus, Junkers, Worcester, Sieger, elm.leblanc, iVT.

Boilers and heat pumps from other brands like Remeha, Vaillant, NIBE, Panasonic, Viessmann etc are NEVER compatible with any of the EMS products on this website.

Do not connect any EMS product to an OpenTherm bus, or a 24V or mains power thermostat bus!

EMS devices

The support for EMS devices depends on the firmware of the Gateway.

Each Gateway is preloaded with a stable or otherwise stable beta version of EMS-ESP.

Support for new devices is added with every new release. If your device is not in the list below, it might still be fully or partially compatible. If you are missing parameters you can open an issue on the code repository to get support.

The list below summarizes EMS bus devices that are supported in firmware version v3.6.5 (2024).


All EMS boilers send out the status of about 50 to 70 of its parameters to the bus every 10 to 60 seconds.

The table below gives an overview of boilers that have been tested with EMS-ESP. Lot’s of boilers have a service jack, but a lot of them don’t have it. In the latter case the Gateway connects to the thermostat wires or the EMS bus coonector inside the boiler. Also see the wiki.

There are much more boilers not in the list that are supported.
In general all EMS, EMS+, Heatronic 3 and Heatronic 4 boilers are supported however for some the boiler ID still has to be included in the list.

To make it easier to identify a supported boiler check if it has one of the following control panels. If so, it is compatible.
Some of the control panels might also include a thermostat as well, and the panel color might be white, black or grey.
I have not listed all possible boilers yet, so if the control panel on your boiler looks different, send me email so I can check whether it is supported.

The 4th column will specify if a certain boiler has a service jack. If so, you only need an EMS service cable with your order to connect a Gateway.

For Nefit boilers check the new guide here.

BrandModel/RangeControllerService jackRemarks
NefitTrendLine (II)Yes, on front left of display
NefitTopLineYes, on front right of display
NefitProLineYes, on front right of displayThe ProLine NXT and ProLine ECO are OpenTherm and not EMS. The normal ProLine is EMS though.
NefitSmartlineYes, on front beneath display
NefitEcomline EliteYes, on front beneath displayThe Elite is the only boiler from the Ecomline range with a EMS-bus UBA3. All other Ecomlines use iRT and are NOT supported.
This boiler might have a Moduline 30 thermostat connect via a RCC module. In this case the thermostat won’t be detected. Just buy a Moduline 400 from f.i. Marktplaats in that case.
NefitBaseLineYes, on front left of display
9000i AquaPower
yes, below front cover. Left bottom on control unit.
BoschHR Compact
HRC Compact
Yes, on front right of displayControl panel is either white or black.

There are also non-EMS boilers called ‘Compact’. Only those with the control panel on the left are compatible!
BoschCondens 2500
Condens 2500W
Condens 2500 WBC
NoThis boiler has one single connector for both EMS and on/off thermostats.
If you have an on/off thermostat you cannot use the Gateway (Or only in RX mode). Use an EMS thermostat instead.
BoschCondens 3000WNo
BoschCondens 5000W (ZSB series Australia)NoThe Australian (AU) version of this boiler has also been confirmed to work.
BoschCondens 2300i
Condens 5000i
Condens 5300i
Condens 5700i
If available check right right of display under the hood.
BoschCondens 7000i(W)Yes, on front left of display
BoschGC7000FYes, on front beneath display
BoschCondens 8700iRight right of display under the hood.
BoschCondens 9000i
Condens GC9000
yes, below front cover. Left bottom on control unit.
Yes, underneath the display
EMS may not work if the wire bridge is still installed.
BuderusGB072yes, left of display
BuderusLogamax Plus GB122iyes, on the rear side of circuit board next to coding plug
BuderusLogamax GB172
yes, left of display
yes, underneath display
yes, right side of display below front cover.
Buderus GB192i
yes, below front cover. Left bottom on control unit.
BuderusGB212Yes, left of display
BuderusLogamax Plus GB022 Yes
BuderusLogamax GB125Both the older one
And the newer version with MC110
Yes, below display
BuderusLogamax U052
Logamax U054
Buderus Logamax U052No
BuderusBoiler with MC110 controllerYes, below display
WorcesterGreenstar 8000
Greenstar 4000
4000: Next to the code plug on the rear of the display unit.
WorcesterGreenstar 440CDi
Greenstar 550CDi
Combi Greenstar Highflow CDi
WorcesterSystem Greenstar CDi Classic SystemNoOnly boilers manufactured after 16th January 2007 with software version CF12.10 onward.
WorcesterSystem Greenstar 9i
System Greenstar 12i
System Greenstar 15i
System Greenstar 18i
System Greenstar 21i
System Greenstar 24i
NoOnly boilers manufactured after 2011 and with the option to have an integral diverter valve installed.

For these boilers please open the cover and check whether this connector is actually present. If not the boiler has no EMS bus.
WorcesterCombi Greenstar i JuniorNoManufactured after July 2013
WorcesterCombi Greenstar iNo
WorcesterSystem Greenstar 27i
System Greenstar 30i
Combi Greenstar Si Compact
Combi Greenstar CDi Compact
Yes, right side of front panel
JunkersCerapur CompactNoThis boiler has one single connector for both EMS and on/off thermostats.
If you have an on/off thermostat you cannot use the Gateway. Use an EMS thermostat instead.
JunkersCerapur Smart
Cerapur Comfort
Cerapur ACU
Cerapur Modul
Yes, left of display
JunkersCerapur 4Yes, right side of front panel
Cerapur MaxxYes, right of display
CerapurModul 9000i
yes, below front cover. Left bottom on control unit.
JunkersCerastar Comfort, Ceramini ZWR 18-7 KE | ZWR 24-7 KE | ZSR 18/120-7 KE | ZSR 18/160-7 KE | ZSR 24/120-7 KE
ZSR 24/160-7 KE | ZSR 10-7 KE
JunkersAll with Heatronic 3 controller (ZSB, ZWB, ZWBC)No
JunkersAll with Heatronic 4 controllerYes, right side of display
elm.leblancCONDENS and other gas condensing (Chaudières condensation) models with EMS bus.See Junkers models above. If it has the same control panel, it’s compatible.No

There is a large number of boiler parameters that can be read out, usually more than 50. A certain amount of parameters can also be set by the Gateway. Which parameters you can set really depends on the exact brand, type, year and software version of your boiler. For some boilers you can set a particular parameter, but the boiler will override it again after a few seconds. F.i. boilers that have manual knobs on the front for the max/flow temperature, may not always allow this particular parameter to be set by the Gateway.


The table below provides a list of thermostats and which features are supported.
For some thermostats you cannot change the setpoint via the EMS bus. These have a ‘No’ in the ‘Write’ column.
So for these thermostats you can read the parameters, but they don’t respond to write requests.
Additionally, some of the WiFi connected thermostats don’t send any heating data over the bus, they are ‘detected-only’.

If a thermostat supports multiple heating zones, this will be supported by the Gateway as well. The EMS Gateways also allow control of the boiler without a thermostat in most cases.

What is not implemented for most newer thermostats are the internal heating schedules of the thermostat. This is due to technical limitations. However, you can of course still use the internal schedules or use and schedule switchpoints from Home Assistant.

For Nefit we have a new guide on thermostats here.

Buderus RC10
Nefit Moduline 100
Buderus RC20
Buderus RC20RF
Nefit Moduline 200
Buderus RC25YesYes
Buderus RC30
Nefit Moduline 300
YesYesThe Moduline 300 supports EMS but also iRT, so make sure you have an EMS boiler.
Buderus RC35
Nefit Moduline 400
YesYesThe Moduline 400 supports EMS but also iRT, so make sure you have an EMS boiler.
Buderus Logamatic TC100
Bosch Easy
Nefit Easy
YesNoYou can view the setpoint, but this thermostat does not respond to write requests. There are other projects that allow this via the XMPP protocol.
Bosch Easycontrol
NoNoThis thermostat does not send any heating data over the EMS bus. The Gateway can see its presence, but that’s it. You can’t read or write the temperature via EMS.
The problem is a shortcoming of this specific model of thermostat and not of the Gateway. Therefore in its current state it can never be supported by any future firmware update of the Gateway (But you can see the boiler parameters with the Gateway of course).
Nefit Bosch RT800Bosch RT800
Bosch CR120
YesYes(CR120 is still in development)
Buderus RC100(H)
Nefit Moduline 1000
Nefit Moduline 1010(H)
YesYesThe Moduline 1000/1010 supports both EMS and OpenTherm. Make sure your boiler is EMS!
Junkers CR10(H)This one is likely the same as the Buderus RC100.
Bosch CW100
Bosch CW 100 RF
Bosch CR50 (AU version)
Buderus RC200YesYes
Buderus RC300
Buderus RC310
Nefit Moduline 3000YesYes
Bosch CW400YesYes
iVT T120 RFiVT TR120RF, TR120 RFYesYes
Junkers FR10YesYes
Junkers / Bosch FR10
YesYes/No* Most Junkers thermostats are only writable for production date August 2008 (code FD 889) or later. See the table here on how to convert the code on the thermostat to the production date.
Sieger ES72YesYes
Sieger ES73YesYes
Tado thermostatTadoYesNoThe Tado thermostat emulates a Buderus RC10, but not perfectly.
You cannot write the setpoint via the EMS bus. So only read for this one.
(For HA you can use the Tado integration aside from the Gateway products for full control of your heating system)

Heat Pump Modules:

All EMS heat pumps send out the status of about 80 to 100 (some more than 150!) of its parameters to the bus every 10 to 60 seconds.
The table below gives an overview of heat pumps that have been tested with EMS-ESP. For the heat pumps a lot of parameters are available. With every firmware update new ones are added as well. F.i. in the latest beta it is possible to change the maximum compressor power on some pumps and switch the PV and Smart grid input virtually.
Most or all heat pumps have a service jack that is on a cable inside the housing. Also see the wiki.

For most hybrid systems that include both an EMS heat pump and an EMS boiler you can only read out the heat pump OR the boiler with one Gateway. If you want to read out both you need two Gateways. Contact us for a discount.
Only for hybrid systems with a HM200 hybrid manager you can see both at the same time.

Bosch often uses the same models of heat pumps for each brand, so you get the same heat pump with a different brand label and model name on it. In general if you remove the front panel and see a grey installer board like below your heat pump is compatible. Also if it has f.i. a HMC300 or HMC310 control panel it will be compatible.

Some brine/ground heat pumps like the Buderus WPS only have a CAN bus, if you are unsure whether your heat pump has an EMS bus just send me an email via the contact form and I will check.

For Nefit/Bosch we also have a more detailed guide HERE.

BrandModelInstaller board /control panelRemarks
and other EMS based heat pumps like
3000i, 7800i.
Installer board inside the unit should look like the image on the left.
Check the inside if it has a service jack cable like this HERE

f.i. WLW176i, WLW186i,

With the regular grey installer board or the newer BC400 XCU-THH (XCU-HY) control module.
Installer board inside the unit should look like the images on the left.
Check the inside if it has a service jack cable like this HERE .

Very old heatpumps only have a CAN bus.
all models hybrid and full-electric, solar, split, mono block.

With the regular grey installer board or the newer XCU-THH (XCU-HY) control module.

The very first Enviline did not use the EMS bus. All other should be fine.
Check the inside if it has a service jack cable like this HERE
JunkersCerapur Aero, Supraeco SAS Hybrid, etc

Not all Junkers heat pumps have an EMS bus!
Check the inside if it has a service jack cable like this HERE
IVTModels with EMS bus
Vent 202
Air x
Geo 500, 50x
Geo 508C,
Geo 608C
with rego 2000, rego 3000.

Check the inside if it has a service jack cable like this HERE
elm.leblancCondens Hybride

You get at least 60+ parameters like pump modulation, flow, setpoint/actual and return temperatures, all total energy values for delivered heating, cooling, and for which mode (warm water, heating) and the total energy consumption for each mode in kWh. With most hybrid systems you can only read out either the heatpump side or the boiler side, as these systems have two independent EMS bus systems.

Domestic ventilation units:

The latest Logavent HRV ventilation units have an EMS bus. We are working on initial support for these units. A lot of telegrams are still unknown. So don’t expect a lot of data points for now (basically don’t expect anything in this phase).

BuderusLogavent HRV176

Heat interface unit (HIU) / Wohnungsstation

A heat interface unit is basically a ‘boiler’ with no internal boiler, but a heat exchanger for external heat sources like district heating and applications with a centralized plant room.

All these HIU units should be compatible if they have an EMS bus, but we still need to add more of their parameters. If you own such a unit with an EMS Gateway please let us know on the firmware repository.

BrandModelService jackRemarks
Worcester BoschGreenstar HIUyesA number of parameters are available now. However this type of heating unit needs a lot more work.
BuderusBuderus Logamax Kompakt WS170

Solar Modules:

The below solar modules are supported. Some are operated stand alone with a thermostat, without a boiler. In this case the Gateway also works.


Mixing Modules:

BoschMP100Pool mixer
* you cannot set parameters on some mixer modules.

Other devices:

The devices below are detected by the Gateway but most of them do not have any meaningful interaction with the bus (They have no parameters you can see or control).

BuderusMC10Type of controller.
BuderusWM10Low loss header mixer module.
BuderusRFM20Receiver module.
AM10Alarm module.
BC10, BC22, BC25, BC40, BC400Base controller. This is the display unit on the boiler with the buttons.
Web KM50
This is the Bosch web gateway. If your boiler/heatpump has an Ethernet port, one of these modules is built in and will be reported as such by the Gateway. These gateways provide their own interface with a Buderus/Junkers app.
iVTK 30 RF, K30RFweb gateway
NefitModuline Easy ConnectAdapter.
BoschEasy ConnectAdapter.
EMS-OTEMS-OT OpenTherm converterEMS-OT converter. (Adding this with a OT thermostat to an EMS boiler will not make the OT thermostat controllable by the EMS Gateway).
JunkersHT3 controllerController.
MC400Cascade controller. This unit adds multiple boilers in cascade to act as one big boiler.
Connect the Gateway on the thermostat terminal on the MC400.
JunkersHM200Hybrid manager for heat pumps
HM10/EM10Switch and alarm module

Devices that are NOT compatible

Some Bosch brands devices that are not compatible are listed below.

Non-compatible boilers

Very old Bosch brands boilers (<2007) might not be EMS based but iRT or another protocol.
Below a small selection of boilers that are known to be incompatible.

BuderusU104, U112, U114, U122, U124, GB112, GB122, Linea Kombi 23.iRT
BoschTronic Heat 3000/3500No bus
NefitEcomline Classic
Ecomline Excellent
Ecomline Economy
UBA 1.0 / UBA 1.5 / UBA 4000 / UBA 4001iRTThermostat is often the Moduline 30.
NefitProLine NxT
ProLine Eco
OpenThermThe non-NxT ProLine is EMS!
24V on/off
JunkersCerapur BalconyNo bus at allMissing ‘BB’ connector
JunkersSome older Junkers boilers use a CAN bus for the thermostat.With BM1 or BM2 CAN bus module.CAN busMight have a TR220 thermostat.
JunkersAll models with Heatronic or Heatronic 2.
F.i. Eurostar ZWE, ZSE, ZSBR.
3-wire bus with Junkers (PWM) 24V The thermostat is usually a TR21, TR100 or TR200.
BuderusEcomatic-M HS3220, HS3204, HS3206Buderus HS3220No busController mainly used for oil boilers
BuderusLogamatic 2105, 2107 etcECO-CANController mainly used for oil boilers
BuderusLogamatic 4000, 4121, 4212ECO-CAN, EMSThe EMS bus on this system cannot be used with the EMS Gateways as there is no meaningful interaction possible.
Bosch4500FMOpenThermThe optional thermostat connector inside is a Siemens OpenTherm plug.
WorcesterGreenstar 12/15/18/24 Ri ErPNo busOnly on/off contact

Non-compatible heat pumps

Bosch has a lot of different models of heat pumps. Although most use the EMS bus, some are CAN only and those are not supported. Especially check if your heat pump has an EMS bus when you own a brine/sole/ground heat pump.

CANLots of other Supraeco models are supported.
BoschCompress 6000 LWM
Compress 7000 LW
CANLots of other Compress models are supported.
BoschCompress 2000 AWF
4/6/8 R-S
10/12/14 R-T
No busThis device has no inside unit and no EMS bus.
BuderusLogatherm WPS 6-1, 8-1 etcCANLots of other Logatherm are supported

Non-compatible thermostats

Below some thermostats that are not compatible. If you have such a thermostat, the boiler won’t be compatible as well.

Nefit Moduline IViRT
Nefit Moduline 10iRT
Nefit Moduline 20iRT
Nefit Moduline 30iRTThis thermostat was used often together with a Nefit Ecomline boiler. However, early EMS boilers sometimes also use this thermostat via so called RCC module.
Nefit RCC ModuleEMSThis module allows you to connect an iRT thermostat of the above to an EMS boiler.
If your boiler is EMS, but has a RCC module and an old iRT Moduline thermostat, remove the RCC module and the old thermostat and buy f.i. a second hand Moduline 400 from Marktplaats. They are only about 25 Euro second hand. This way you have all features and you can set the temperature via the Gateway.
Junkers TR213-wire Junkers (PWM) 24V
Sieger eRS62I2C?
Bosch TRZ200
Junkers TR2003-wire Junkers (PWM) 24V

Other non-compatible devices

All older Buderus Logavent and Junkers Aerastar ventilation systems (No EMS bus).
The latest Logavent has an EMS bus, support is under development.