Worcester Bosch Heatslave 20/25 Hot Water Not Working

[s7e]

Hey there,

I have a boiler (Heatslave 20/25) that had low pressure. I topped the pressure back up to 1 bar using the external filling pipe but the heating still won't come on.

Do I need to reset anything?

Thanks for any help

 

[Aquarius]

the heating still won't come on.

The heating or hot water? If the heating, is the room stat up to max?

 

[SJB060685]

Overheat limit stat tripped?

 

[s7e]

Overheat limit stat tripped?

Thanks - tried resetting the overheat limit stat, no luck unfortunately still no hot water. The button just presses in, so don't think it has been tripped.

If you have any other ideas, happy to hear. 👍

 

[SimonG]

Over heat stat as above or pump needs bleeding. Or both.

 

[s7e]

The heating or hot water? If the heating, is the room stat up to max?

Thanks - it's the hot water that is not working, the central heating is fine.
[automerge]1597506850[/automerge]

Over heat stat as above or pump needs bleeding. Or both.

Thanks- tried the overheat limit stat, no luck. Will look into bleeding the pump.

 

[SJB060685]

Thanks - tried resetting the overheat limit stat, no luck unfortunately still no hot water. The button just presses in, so don't think it has been tripped.

If you have any other ideas, happy to hear. 👍

Hi again. I apologise, I misinterpreted your description of the problem and imagined you had neither heating or hot water.
Have you by any chance knocked the operating switch off or is it off at the programmer?

 

[s7e]

Hi again. I apologise, I misinterpreted your description of the problem and imagined you had neither heating or hot water.
Have you by any chance knocked the operating switch off or is it off at the programmer?

No worries at all - I've doubled checked the programmer and set the hot water to the On position, which is normally when it would turn on, but nothing unfortunately. I thought the problem was the low pressure, but I've topped up since, but still no luck.

 

[SimonG]

Need to check operation of flow switch.

 

[s7e]

Need to check operation of flow switch.

Thanks Simon - When I turn the hot water tap on I can here the pump working would that mean the flow switch is operational and working ok?

 

[SJB060685]

If the pump energises when you open a hot tap that suggests the flow switch is OK but if the burner isn't igniting then there's another problem.
Someone with a multimeter and whos familiar with electrical testing should take a look for you.

 

[s7e]

If the pump energises when you open a hot tap that suggests the flow switch is OK but if the burner isn't igniting then there's another problem.
Someone with a multimeter and whos familiar with electrical testing should take a look for you.

Thanks for advice, yeh, starting to wonder if it's an electrical fault.

 

[SJB060685]

When the operating switch is on or the programmer is set to on the burner should be constantly topping up the store temperature when needed to supply HW when a tap is opened. If this isn't happening and the burner also doesn't ignite when theres a demand for HW then I would be looking at the relays on the PCB. If it is an electrical fault then its just come at bad timing when the pressure dropped.