Worcester bosch greenstar 28cdi compact not working

skyn3t

Hello,

I bought a tado X system, and after disconnecting the rainbow of the old thermostat, and connecting according to the setup instructions the system only responds to Boost Heating or if I use the switch to the turn the hot water on/off.

I reconnected again the old Salus RF Thermostat, and everything is working as before.
The Tado wireless receiver doesn't fire up the boiler when I'm using the App or the Tado Thermostat even after being on the same room.

I'll post some pictures later when I'm on my laptop

policywonk

According to the specifications we've found that's a combi boiler which can run in two modes (1) in old school on-off switching or (2) with digital throttle controls enabling it to run efficiently, called EMS-BUS.
Salus RF thermostats seen to be all designed to handle the boiler in on off switching mode, not digital EMS-BUS.
The Tado X system can handle an on-off switching system, and a digital throttle system, but not the EMS BUS version.
Questions:
When you bought the X system, was it after you got Tado's recommendation? How long ago? Unless you have a hot water cylinder run with a thermostat, or have a very large old house, the X series doesn't make sense, but the V3 series would work with that boiler in digital mode.
So if you are open, would recommend the return of the X system and a purchase of Tado's recommended V3 products for that boiler. If uncertain, contact Tado via their support email address and get the formal clarification. They should a full written set of instructions which would lead to your boiler being more efficiently run.

Does this make sense? Need to go through anything in more detail?

Another thing. When you refer to a rainbow of the old thermostat, did you actually mean the ribbon of the internal controller?

skyn3t

Hello @policywonk thank you for your reply :)

Currently my Salus Thermostat is working on a on-off switching, I program the times it goes on-off and what the temperature it should reach, and if I manually change the temperature (u/down) it stops /starts the heating.

I bought the Tado X on Amazon when I was looking for smart

. I went to the X due the fact it was the latest version and assumed would work with Combi Boilers like Worcester. I followed the guided instructions for the installation when selected my boiler.

I can return the Tado X and get the V3 if works better and as a better compatibility. How can I install / use a the EMS-BUS to run it more efficiently?

Another thing. When you refer to a rainbow of the old thermostat, did you actually mean the ribbon of the internal controller? - Yes, so my Salus is connected to the Front of the boiler using a "rainbow cable" that I disconnected, other wise it would take ownership of the controls and not reacting for example to the boost of the temperature).

Does this sound right or I am missing something else?

Thank you,

Claudio

Attached are some pictures of the current setup with the Salus

Boiler:

Salus RF:

Connection to the Boiler:

skyn3t

I followed this guide to Install the Tado X

PR04_-_Installation_-_Greenstar_CDi_Compact_-_ENG_3.pdf

policywonk

There's a lot of information here. Keep it. Make sure you send it to Tado Support by email, complete with photographs, so that they can see the boiler model, the fact of that ribbon connection. Explain that you were informed here that the V3 series can talk to that boiler in HT-BUS mode, but that you will need a complete wiring instruction guide.

There are a few threads on this community where people have installed Greenstar combis with Tado V3 to interface to EMS-BUS, successfully. Some people panic so one has to look at the process carefully. Am pretty sure that the ribbon will need to be unplugged, along with the Salus, but Tado Support must give you the complete process for change. If they dont mention it, ask again about what you must do with that ribbon.

Wait until they provide you with the information. If you are comfortable making the change, you can complete it in under 3 hours. Wait for a warm week though!

Come back if you need more help. Others on this community have done it and can be woken up to help if you need it.