I hope someone can give me some ideas? I have a Halstead Finest Gold and I am experiencing a problem with the heating switching on after demand for the H/W has ceased. The heating will come on without the clock being activated. I believe it may be the DHW flow switch as when I tap it the heating switches off as it should, there is also slight water seapage where the switch fits onto the main body and the clip used to secure it has perished.

My question is, to replace the valve the switch connects to I would presume I have to isolate the cold water feed and drain the radiaters thus relieving the pressure so I may undo the valve? Will I be able to clean and refit the old valve or as it leaks do I replace it? At this stage I am unsure if it just needs resealing? Also does anyone know the part number for the valve thing i.e the plunger bit which activates the microswitch.

I am crossing my fingers that I have explained it well enough for someone to offer there advice.

Thanks. Nick

Nick, March 2009

Thanks for the help all sorted now, new dhw flow switch and front seal also replaced prv and over flow flexi pipe and cleaned the venturi. Sorted one problem but still cuts out occassionaly when running hotwater. Today replaced a corroded radiator which had leaked at some time and put in some rust inhibitor. Any tips on the cutting out would be helpful and greatfully recieved. Halstead finest Gold Gas boiler.Thanks.

p.s could not see how to enter on-going comments so had to enter as question!

Nick, April 2009

Thankyou for your description on how to repair my Halstead boiler. I wonder if you could explain how to remove the DHW flow swith as the retaining clip has perished. I cant see how the clip would have been removed in the 1st instance had it been whole?
Thanks

Nick, March 2009

To replace valve, isolate flow, returnand cold feed at bottom of boiler, release pressure via prv and open hot tap remove micro switch and undo all unions connected to diverter valve, have bowl to collect any water loss as they have tendancy to air lock and can get messy, remove valve and replace with new part, make sure you replace all washers and o rings, then repressure boiler and the close hot water tap and open all isolation valves to locate part you'll need th GC no from data badge

STE, March 2009