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Greenstar Boiler Controls

Chester Member Posts: 83
Hi all. I'm installing a Bosch Greenstar 57. It looks like Bosch have a relatively new control system that includes a CZM 100 "Comfort Zone Manager" and a pair of thermostats they call "Comfort Room Controllers" (CRC 100 and CRC 200).

I like the idea of having an indoor sensor that would intelligently complement the ODR. Does anyone have any experience with these or opinions to offer? I can't find much information about how they actually work.

Thanks in advance.


  • Robert O'Brien
    Robert O'Brien Member Posts: 3,322
    I saw them in person for the first time at the OESP show last week and I'm also not sure exactly how they work. The control is basically a 3 zone switching relay and will work with the Greenstar with or without the FW200. Don't know if the room controls provide indoor feedback in the manner of the BFU room sensor
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  • Tim McElwain
    Tim McElwain Member Posts: 4,466
    edited May 2015
    What I know is that the Greenstar 57 uses a Heatronic Boiler Control. The CZM 100 Comfort Zone manager is for operating either zone valves or circulators much like a lot of control panel type setups we see today. It is expandable to three modules allowing for a maximum of 8 zones. If zone valves are used a seperate transformer must be installed. The CRC 100 is an integrated temperature sensor that can be used as just a boiler control or works in conjunction with the CZM 100. The CRC 200 is programmable that is the difference from the 100.

    These controls have been used with GB 142 and GB 162 Series of Buderus/Bosch boilers and have a good track record.

    The CRC 200 has a backlight that will display boiler temperature, target temperature, and outdoor temperature when an optional outdoor sensor is installed. It can also operate the Domestic Hot Water Tank in parallel with the clock program or continuously. It is compatable with the CRC 100 for just zone operation.
  • Chester
    Chester Member Posts: 83
    Thanks for the responses. Do you know if these replace or complement the FW200 control?
  • Tim McElwain
    Tim McElwain Member Posts: 4,466
    I am not sure you would have to check with Bosch. I do know the FW 200 Boiler Energy Management System does have system configuration so it may be able to match up. It however seems to only allow for 2 heating circuits and a domestic hot water configuration. You may be causing control confusion which on all this new equipment tends to be a problem. Trying to get control systems to work with one another sometimes is tricky.
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