Heatmiser UH8 Wiring Centre and Vaillant System Boiler

[Markyuk5]

Hi,

In the process of installing a Heatmiser UH8 wiring centre with out Vaillant 637 ecotec plus. The Vaillant has a permanent feed (L E N) and a 230v RT connection.

I'm just trying to work out the right way of installing the 'Boiler Enable'. Heatmiser say it's a 'volt free' switch, which I believe is just like a relay (i.e. it just makes and breaks contact similar to a light switch).

I've put a few notes on the image below how I was proposing to do it - the heat enable making and breaking a live feed from the boiler spur - but wanted to check I wasn't going mad and doing something bad.

Uh8-2-5 A

• Markyuk5
• 29 Sep 2017

Thanks in advance!

 

[Munders]

I am stuck at this exact point. How did you get sorted

 

[Terrywookfit]

LS to PL and LR to boiler

 

[Munders]

Is LS to PL just a link on the wiring centre or is the connection directly into the boiler along with the switch live at the boiler. Thanks, Lee.

 

[Terrywookfit]

Heat Enable


This is the main call for heat for the system, there are 3 connections;

LS = Live Supply

E = Earth

LR = Live Return

Electrically this is a volt free switch, whatever supply is placed on the

LS connection, is fed to the LR connection when there is a call for heat.

Link at wiring center!!
If linked at boiler it would bypass the enable relay.