glow worm 40ff pump over run problem

[DIYDarren]

I have a glow worm ultimate 40ff boiler with a danfoss 4033 timer. This week I have soldered up a few dry joints in the PCB this week and replaced the R11 resistor as it wasn't allowing the boiler to fire up it was just "cycling" if that makes sense. And all seems to be ok again. I thought I would tackle the issue of the CH pump running all the time. I thought this was down to some wiring issue up in the wiring centre next to the HW tank.


But on checking the pump it's getting a constant feed all the time. Back at the PCB end I have disconnected all the wires going out from the PCB choc bloc conector to the timer unit just leaving the mains feed to the PCB. I am getting a constant feed out of I think it's the purple wire (pump feed ) off the PCB,upto the choc bloc connector.This is even when the boiler is off and has been off all night . could this be another quick fix within the PCB or is it a common fault and am I better off getting another PCB.

Thanks for any help.

 

[DIYDarren]

still having this problem guys. I am wondering what tells the pcb to keep powering the pump. Is there a component in the boiler that may be faulty like some sort of temp sesor or such like that sends the signal to the pcb.

Thanks for reading

 

[dazza1974]

Hi there, just wondering if you know what resistor the r11 is as mine has gone too. Thanks

 

[45yearsagasman]

If the value is not visible on the component, then you may struggle to find a replacement. It is not advisable to repair sequence boards unless you are competent to test all the other functions that this board performs. Get a new board for your own safety.

 

[Chas12431]

Hi the pump over run on this boiler is controled by a timer in the pcb, as this bolier can be used on a gravaity hot water system and does not require the pump to contected to the PCB when used like this, you could just wire the pump in to the extrnal contols and link out K1 and K2 the overheat stat as per the manufaters instructions. although i would not recomend this repair i would change the boiler PCB

 

[Agile]

I think that you will find that it is 27k but as it runs hot it may not have failed even if its is discoloured.

You need to MEASURE it !

Tony