Leaking SIKA Flow Switch

[airfrog]

I have an old Firebird Combi 90 oil-fired boiler. Last week the SIKA flow switch sprung a leak. The fitting isn't loose, there is a crack in the plastic. My knowledge of boilers is pretty much non-existent, but the part does look deceptively simple to replace: you remove the old switch, screw on the new one and connect the wires.

So my question is: is it really that simple? Or am I asking for trouble by trying to replace the part myself?

The boiler is otherwise working fine. I just need to close the mains valve when the hot water is not in use to stop it leaking.

 

[jackthom]

Is it one of these? Should be very easy to fit if access is good.

Untitled

• jackthom
• 12 Nov 2014
• 1

 

[Boilerman2]

This type of switch is renowned for leaking! your method statement looks fine but two points TURN OFF the cold water main, then open up a hot tap to discharge the trapped water under pressure before starting work, secondly make sure that the new switch is in exactly the same orientation (there is an arrow on the switch body, make sure this arrow points the same way on completion

 

[airfrog]

Thanks! I might give it a go myself in that case. I will indeed close the mains valve and open a hot tap before replacing it.

The image in Jackthom's post looks exactly like the unit I have. Can you recommend a good place to buy one from? From internet searches all of the sites I have come across are charging £60 - £80 for one.

Thanks again!

 

[PotatoHead]

You can try ordering from Heating World of Spares, although they are trade only. Just under £50 inc VAT.

It might also be worthwhile getting hold of some silicone grease for the rubber o ring, it sits on the copper valve body the flow switch screws onto.