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Uk installation

hughhugh UkMember

Hello all, anyone have any insight in a 240 volt installation, i have a combination boiler/furnace. I have a 12.5 ma 240 to 24ac volt transformer supplying live (hot) to Rh, neutral (common) to c, should the ecobee4 start up? I also have a connected 24v relay (which works) to supply 240 v to boiler. But, the ecobee4 does not light up. Any suggestions? Thanks, Hugh.


  • kevinmcckevinmcc Macomb, ILMember

    May need to ask Ecobee. The 24ac is correct voltage. I do not know if 50 Hz vs 60 Hz frequency would matter or not.

  • TopcatTopcat UKMember

    Sounds like E4 is broken. 50Hz is fine, but small transformers have poor regulation, so on light load voltage can be +20% or more, eg 29v which is too high, so measure it. Instead buy 240 to 18 v AC transformer rated 6VA ( or watts) or greater from RS Components in UK eg RS 201-7016. Over last 3 years I have installed seven Ecobee 3 in UK all running well. The relay MUST have a 24v AC coil eg RS 353-843. A DC coil relay will overload the Ecobee output.

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