worcester greenstar 28 i junior

[desrob]

blue light flashing constantly, when hot water is called for the boiler fires ,there is no hot water going to tap it is all getting dumped down the flow,how do the diverters work on this model, i did get diverter motor to work a little bit but the water went down both hot tap and flow, am i right in presuming diverter problem or am i missing something,there was no m.i.

 

[GrahamM]

Is the blue light a fast flash or a slow flash? Is it off or on with no demand? CH ok?

The divertor works by the motor pushing a leaver to divert the flow. You can take cover off and see it operating with demand.

 

[desrob]

Is the blue light a fast flash or a slow flash? Is it off or on with no demand? CH ok?

The divertor works by the motor pushing a leaver to divert the flow. You can take cover off and see it operating with demand.

blue light fast and on with no demand

 

[desrob]

divertor motor seems to be struggling to do any thingand could a blocked plate give same symtoms,could diverter be brokenand not diverting?can you help

 

[desrob]

can you help..

 

[nysk2008]

Hi Desrob,

Check the following: Flow Turbine, Diverter Valve and NTC Sensor - do you know if the diverter is a type 1 or type 2?

 

[danny@phase]

Desrob - I would remove the divertor valve motor from its housing to check its operation, if not as expected check output from circuit board (ST17). Also check the NTC Sensor (8-20 Kohms). If you think the divertor valve motor is dodgy you can always keep a spare in the van (same as BMW wing mirror motors, available at the local scrapyard for testing purposes!).

Let us know how you got on?

 

[GrahamM]

As mentioned above a fast flash generally points towards a temp sensor fault. That would be my first port of call.

 

[desrob]

As mentioned above a fast flash generally points towards a temp sensor fault. That would be my first port of call.

sensor is fine,going back tommorrow to strip diverter hopefullythe faults there,bmw mirror motor, classic,obviously the car of choice for the heating engineer.

 

[desrob]

Hi Desrob,

Check the following: Flow Turbine, Diverter Valve and NTC Sensor - do you know if the diverter is a type 1 or type 2?

type 1 - type 2...?

 

[GrahamM]

Next port of call would be the fan. The fast flashing blue light usually points to an electrical issue relating to temp sensors, fan or PCB. Do not think this would be related to a faulty div valve.

 

[desrob]

Next port of call would be the fan. The fast flashing blue light usually points to an electrical issue relating to temp sensors, fan or PCB. Do not think this would be related to a faulty div valve.

i think your right in saying the fan is not linked and i'm sure it isn't,when asking for dhw it is dumping down the flow the boiler is operating fine this to be suggest the fault is with diverter motor or valve or both..?

 

[desrob]

Next port of call would be the fan. The fast flashing blue light usually points to an electrical issue relating to temp sensors, fan or PCB. Do not think this would be related to a faulty div valve.[/QUOT

 

[RoryD]

no divertor on 28i junior but it has an aqua sensor (flow switch). Aqua-sensor readings
White wire to Black wire, expect 5 VDC constant.
Green wire to Black wire. No DHW demand, expect either 5 VDC or 0 VDC
With a DHW demand expect 2.5 VDC.
If all that is ok then we have to look at the heat exchanger - the lefet hand side is DHW

 

[desrob]

it does have diverter motor and valve

 

[nysk2008]

Hi Desrob,
Carry out diverter valve motor test at the PCB end of harness - when lever is up it is in DHW mode if type 1 motor 170ohms +/- 20% or type 2 motor should be 240 ohms +/- 20% check red to orange, orange to blue, yellow to green and green to black. Check the NTC sensor and continuity of leads, check you have 230v ac across live (purple) and neutral (brown) on fan, check continuty of fan lead and check code plug is inserted properly. Was only on a worcester i junior course last week so hope this helps. Cheers Neal

 

[Billy Bob Bob]

right so its dumping down forget the ntc its not in the equation ,you have 1,a faulty dv,2 a faulty plate heat(if fitted) 3, unusual but it happens a faulty mixer tap/shower

 

[desrob]

would you believe it, they, worcester have changed the diverter motor, fair enough but was there any need to change harness connection,meaning you have to buy that aswell,when i took the harness of at the pcb end, there was a black scorch mark and a little hole in the area were the divrter motor harness connection goes, this could be the fault, but some thing caused board to do this, so would you change the pcb and the motor to be on safe side,thanks in advance

 

[arran197]

If the blue light is flashing rather than being a solid blue light, then there is a fault somewhere. And if the board is scorched then I would change that.