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Feb 2, 2020
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Hi - new to the forum, thanks in advance for any advice.

I have a Greenstar 30cdi boiler with currently a boiler mounted FW100 weather compensation controller. I would like to wall mount the FW100 to replace the old Honeywell T6360-1028 mechanical thermostat which is currently in the hallway and is supplied by a 2 core cable.
I've tried simply replacing the Honeywell with the FW100 but once power is resupplied to the boiler the FW100 (when wired up in the hall) remains unpowered.
Is this simply a job of rewiring the Heatronic 3 motherboard in the 30cdi to accept the FW100 as wall mounted or does the FW100 if wall mounted require more than the 2 core cable that is currently supplying the Honeywell.
I've attached what I think are the relevant screen shots from the FW100 manual and the wiring schematic from the Heatronic motherboard in the 30cdi.
Cheers,
Dan
 

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Unless you are knowledgeable and confident, you should get a heating engineer to make this change. You can inadvertently cause expensive damage by making the wrong connections.

In simple terms the two units (Honeywell and FE100) feed into different parts of the control unit. From your description above you have connected the FW100 to a switched connection rather than the correct bus connector that links it to the external sensor. Once the Honeywell connection is removed that also needs to be reconfigured before the correctly wired FW100 will work.

Also be aware that when the FW100 is panel mounted into the boiler fascia it is a three pin ( rather than 2 core) connection - the third pin being used to “tell” the boiler that the unit is mounted into the boiler.
 
Understood.

I suggest you do it in two phases.

Phase 1 - remove the Honeywell controller and get the system to operate with FW100 mounted in the boiler fascia.

When that is working ok to your satisfaction

Phase 2 - relocate the FW100 to a wall mounted location
 

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