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Replacing EPH R27-HW 2 zones programmer with smart thermostat

  • 05-04-2024 10:13pm
    Registered Users Posts: 915 ✭✭✭

    Hi guys,

    Currently I have installed 2-zones (heating and water) R27-HW controller with manual (knob operated) temperature controller and as its installed in very corner of the room almost behind shelving unit, its almost impossible to change settings without moving everything around.

    For some time thinking about replacing it with smart setup which can be controlled by Google Home but not sure where to start and how would be possible to replace 2 units (controller and thermostat) with one, lets say Nest (or similar) or RF setup (receiver plus wireless controller).

    Any feedback deeply appreciated.



Best Answers

  • Registered Users Posts: 349 ✭✭McHardcore

    yes, it’s possible. There are Nests that allow you to control both heating and water.
    The Nest comes in two parts: the wireless thermostat, and the Heatlink receiver.

    You will be stripping out the current controller and replacing it with the heatlink.

    You can place the nest thermostat anywhere in your house and power it from a 5v wall adapter.

    Before you strip out the controller, unscrew it from the wall and take a photo of the wiring. Use the products wiring documentation to label and identify each wire. Draw out how you will wire them up to the Heatlink using the heatlinks wiring documentation. They will be pretty similar.
    when you are comfortable, and maybe confirmed the wiring with other folks, then strip out the previous controller with the new one.

  • Registered Users Posts: 5,369 ✭✭✭DublinDilbert

    Fit a hive system, then you can place the thermostat anywhere you like. Depending on how your wiring is done, you might need to by-pass the existing hardwired thermostat.


  • Registered Users Posts: 915 ✭✭✭stuff.hunter

    Thanks guys,

    it's hard to decide which one so I'll describe my current setup in full.

    boiler: Worcester Greenstar 15i System ErP Heating and water)

    controller: EPH R27-HW + EPH manual knob thermostat.

    Now, the question is:

    to replace controller with Nest (which one?) and this wouldn't require any work on boiler itself (my presumption)


    instal Hive which will require to hook the controller module up to boilers PCB, pretty much straight forward but what will happen to 'old' controller and thermostat? Would I need to take it out?

    Apologies for asking so many questions, I'm pretty familiar with electronics, PC hardware, network cabling etc. but wiring heating scares me badly.



  • Registered Users Posts: 5,369 ✭✭✭DublinDilbert

    Hive just replaces eph timer wherever that is located. Eph timer is removed. Depending on wiring old room stat might need to be bypassed, but probably not.