koi pond heating via gas combi boiler controlled through a Carel S 90 TW Tem

[wongy]

Hi hope you can help.

Friend has just changed his gas boiler from a standard wall mounted one. To a combi boiler. Pond temp Is controlled by a Carel S90 TW (He has no wiring instruction.) Tem sensor sited in pond. Stainless steel heat exchanger. All worked fine until boiler swop.

New boiler is an Heatline combi Electrics are 230v L-N-E from 13 amp switched socket outlet, fused 3amp into boiler. L-N-E linked into Carel. Loop pair out of boiler to Carel . The pre-fitted loop (24 v) has been removed.

By playing with the loop connections at the Carel I can get the boiler to fire,but it does not shut down when Carel temp. Is satisfied.


Change connections at Carel boiler does not fire up. referring to Heatline wiring It shows 230 voltage being feed from both ends of the connector in the boiler. I wonder is voltage feed from the Carel thus causing the boiler to stay on.
Any suggestion's . Or is this temp controller not suitable.


your my only Hope

 

[monkeyelectric]

Sounds like it needs wiring through a relay

 

[Marvo]

Try substituting the controller for a push button switch just to establish if the boiler fires-up and stops when you press and release the button. If it does then either it's probably a wiring issue or the Carel controller isn't compatible with the boiler in which case you may need a relay in between then as Monkeyelectric suggested.