Replacing Horstmann receiver with a Honeywell BDR91

[Rossie250]

Hi

No expert here sorry!

Just brought my Honeywell set over to my new house and want to replace the Horstmann that's here.

Honeywell had 2 com wires and a 240v feed on my combi boiler but in the new place the Horstmann just has 3 wires.

I'm not sure I understand the earth at all.

Can anyone shed any light on what it's doing and what I need to do ?

I was thinking of cutting it back using the remaining wires on the a/b and adding a 240v feed to the n/l inputs but I don't to blow anything up.

Any help appreciated

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• Rossie250
• 7 Sep 2014
• 1

Untitled

• Rossie250
• 7 Sep 2014
• 1

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[D_Hailsham]

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• Rossie250
• 7 Sep 2014
• 1

The green/yellow "earth" wire is being used as the switched live to the boiler. This is not allowed, though many lazy installers do it as it saves them having to buy the correct cable.

You should really replace it , using heart resistant cable if wired directly to the boiler.

Wire the BDR as follows:

Horstmann - Honeywell

Brown ------------- L (either)
Blue --------------- N
(Earth) ------------ B

Also link L (either) to A on the BDR91

If you can only get cable with 3-core plus earth, connect the earth to the correct terminal at the boiler and make the other end safe - e.g. in a terminal block.