Potterton Performa HE 30 -no hot water to certain taps?

[mattw1]

When I operate the taps with the highest flow rates the hot water fires up fine.

The taps with a lesser flow rate do not always make the boiler fire up.

The problem is worse when the heating is turned off.

I have been advised this maybe the diverter valve sticking.

Q. Does this sound feasible?

Q. If so - spares sites show these being about £100 , how much do you reckon for fitting?

Thanks

 

[Agile]

About £94 to fit.

But usually the diverter can be repaired with parts costing about £22.

So I would do the whole job in my local area for about £112.

Tony