worcester green star 28i jar poor HW

[alexbetts]

Hi all

been to look at this 28i jar, the HW is very poor only when the flow of water is at its lowest will the water get hot. i changed the NTC didn't work, the diverter is rising and fallen on change over of heating to HW, the plate Hex is cold when HW turned on and i did notice the flow pipe of the heating warms when the HW is running.

could the Plate Hex be blocked. or faulty diverter (was badly covered in brown stuff).

 

[Terry lambert]

It sounds like your on the right track.

I would drain the boiler and check the plate to plate. Also stick your finger in the diverter and see if the paddle is bunged up or if it moves freely

 

[alexbetts]

when you say finger in side i did this to c if there was any muck inside which there wasn't but i didn't want to play with the paddle in case i broke it but it was pretty covered in like brown paste. to clean the hex would it need to be soaked over night in some type of cleaner or should it just be changed have done with it.

 

[Terry lambert]

It sounds like the system needs a powerflush.

After checking the plate, if performance is no good

I would stick some x800 into a towel rail if there is one and shut all of the other rads.

Let the heating run for a couple of hours between the towel rail and boiler, turn the hot water on and off to wash through that side.

Drain and see what you get

You should be able to move the paddle with your finger, don't force it though

 

[Terry lambert]

Obviously ifthe plate is blocked, clean that.

But I would at least run some cleaner through the system, it sounds mank, and you will only get a call back.

 

[alexbetts]

hi guys thanks for the help, the fault was the water main was too high pressure and stopped the turbine from opening properly, when the mains pressure was reduced it worked fine.