Vaillant pump overrun connection?

[crr003]

<div class="bbWrapper">I have a question about wiring pump overrun on a Vaillant ecofit pure boiler (not a combi).<br /> <br /> I had my old boiler replaced in 2019 and there was no provision for wiring the existing pump from the boiler in the existing wiring, and the fitter said it was OK to leave it so the pump switched on and off from the heat/hot water demand.<br /> <br /> I’ve since read about pump overrun and that the boiler should have control of the pump for better heat management. Apparently Vaillant prefer this but they still manufacture/sell a cable that allows no overrun (they call it “3 wire” connection rather than “7 wire”).<br /> <br /> My question – is it worth getting an electrician to come and fit the additional wiring to allow the pump to be controlled by the boiler - how much extra “life” will I get from the boiler using pump overrun?<br /> <br /> The wiring centre (?) is in the loft and it’s about an 8m run from there to the boiler.<br /> <br /> Thanks.</div>

 

[diditrain]

<div class="bbWrapper"><blockquote data-attributes="member: 139079" data-quote="crr003" data-source="post: 1878690" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch"> <div class="bbCodeBlock-title"> <a href="/goto/post?id=1878690" class="bbCodeBlock-sourceJump" rel="nofollow" data-xf-click="attribution" data-content-selector="#post-1878690">crr003 said:</a> </div> <div class="bbCodeBlock-content"> <div class="bbCodeBlock-expandContent js-expandContent "> I have a question about wiring pump overrun on a Vaillant ecofit pure boiler (not a combi).<br /> <br /> I had my old boiler replaced in 2019 and there was no provision for wiring the existing pump from the boiler in the existing wiring, and the fitter said it was OK to leave it so the pump switched on and off from the heat/hot water demand.<br /> <br /> I’ve since read about pump overrun and that the boiler should have control of the pump for better heat management. Apparently Vaillant prefer this but they still manufacture/sell a cable that allows no overrun (they call it “3 wire” connection rather than “7 wire”).<br /> <br /> My question – is it worth getting an electrician to come and fit the additional wiring to allow the pump to be controlled by the boiler - how much extra “life” will I get from the boiler using pump overrun?<br /> <br /> The wiring centre (?) is in the loft and it’s about an 8m run from there to the boiler.<br /> <br /> Thanks. </div> <div class="bbCodeBlock-expandLink js-expandLink"><a role="button" tabindex="0">Click to expand...</a></div> </div> </blockquote>Getting that heat away from the boiler after there is no longer any demand is obviously the best option. If the wiring run is through the loft then it shouldn’t be to difficult or expensive to rectify. Is your pump located in the loft as well as the wiring centre?</div>

 

[crr003]

<div class="bbWrapper"><blockquote data-attributes="member: 1886" data-quote="diditrain" data-source="post: 1878759" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch"> <div class="bbCodeBlock-title"> <a href="/goto/post?id=1878759" class="bbCodeBlock-sourceJump" rel="nofollow" data-xf-click="attribution" data-content-selector="#post-1878759">diditrain said:</a> </div> <div class="bbCodeBlock-content"> <div class="bbCodeBlock-expandContent js-expandContent "> Getting that heat away from the boiler after there is no longer any demand is obviously the best option. If the wiring run is through the loft then it shouldn’t be to difficult or expensive to rectify. Is your pump located in the loft as well as the wiring centre? </div> <div class="bbCodeBlock-expandLink js-expandLink"><a role="button" tabindex="0">Click to expand...</a></div> </div> </blockquote>Thanks for replying!<br /> The pump is in the loft about 1m away from the wiring centre.<br /> Another thought - the Vaillant has L/N/E connections for the pump; but if the pump is already getting N and E from the Wiring Centre, do I really only need the &quot;pump on&quot; L connection running from the boiler up the wall into the loft?</div>