Worcester oil Heatslave flow switch sticking

[ukml]

Hi, can anyone help me. We have a five year old heatslave boiler and the flow switch intermittently sticks on even when the timer is off. Consequently the pump runs continuously until I tap the switch or wiggle the wire going into it. Tried a new switch but its still doing it. I can't make it occur it is very intermittent and driving me mad as boiler is in outhouse and invariably we notice the pump running just as we have gone to bed. HELP!!!

 

[oilhead]

When fitting the flow switch, did you put the paddle square to the pipe or at a slight angle?
Have you cleaned out the pipework below the flow switch?

 

[ukml]

Hi Oilman, thanks for the reply.
The pipework is definitely all clean, with regard to the fitting angle of the spade, I think it is square on to the flow. Is this correct?

The switch was actually replaced twice under the warranty by Worcester when the boiler was new but it never solved the problem and stupidly I didn't pursue it with them, I have since replaced it once but as I said above it still does it.

 

[oilhead]

The paddle should be slightly angled to the flow.

 

[ukml]

Thanks for the info, I will check it at the weekend and angle it if required.

 

[Agile]

The switch was actually replaced twice under the warranty by Worcester when the boiler was new

That sounds as if its a generic fault with that boiler model!

 

[ukml]

The switch was actually replaced twice under the warranty by Worcester when the boiler was new

That sounds as if its a generic fault with that boiler model!

You may well be right but I can't find any reference on the interweb relating to this specific fault and needless to say Worcester Bosch are not admitting anything. I should have pursued this while it was still under warranty but got fed up with taking time off work to wait for an engineer to come and tell me what I already knew.

 

[oilhead]

When the flow switch has been replaced, has the complete unit been replaced, or just the plastic part that contains the switch?

 

[ukml]

When the flow switch has been replaced, has the complete unit been replaced, or just the plastic part that contains the switch?

To the best of my knowledge the whole switch was changed twice and on one occasion the top plastic part only.

 

[ukml]

Removed it this morning, all cleaned out and refitted slightly angled to the flow (thanks oilhead) hopefully that will have done the trick. If not, I will fit an alternative switch.