Vokera Linea -HW but no CH

[anisa]

I have a Vokera Linea (24-28 range) boiler and cannot get the CH to operate. Last winter I had a leak and turned off all the radiators. Have subsequently had the valves replaced as they were quite old but cannot get the CH to turn on using the timer or the constant switch.

I can switch them on using the manual override, but this causes them to overheat, and the pressure rises above 2 bars. There is also an LO code displayed on the boiler digital display, which can only be got rid of if I switch the boiler off (this also turns the CH off which does not turn on again without going through the manual override again)

Any advice at all would be appreciated!!
thanks

 

[weargas]

Turn the centre selector switch to the middle position. Does the power light and the display go blank??? If by manual over-ride you mean you remove the cap on the fascia and press the button then don't!! It's not a manual over-ride, it puts the boiler into a heating engineers combustion analysis mode which makes it fire on full gas without shutting down. It also shows CO on the display (not LO) whilst in this mode. Oh yeah, if the power light and display don't go out when you turn the middle selector to the central position then you're knob has snapped internally (ouch). It's a common problem with the linea range and a modified knob is available as a replacement.

 

[anisa]

Thanks for your reply
That's exactly what I did i.e. removed the cap and pressed the button oops!!
When the middle selecter is turned to the central position, the power light and display do go out -we though that the selecter might have been a problem and replaced with a new one just to be sure but this hasn't made any difference.

They were also bled recently (or so I've been told by my handy-man around the house!! ....how can I check?), but the problem still doesnt seem to be resolved. This morning however, I turned the switch to the CH position, and the boiler fired up for the CH for about three seconds and then stopped -not sure what that means

The CH was absolutely fine until I had that leak last winter -does this sound like a common problem after a leak?

 

[Agile]

You could always check that BOTH the CH flow and return valves just under the boiler are really turned on!

Tony

 

[weargas]

It does sound like it could be the diverter valve actuator not operating. You'll need someone with knowledge of the boiler to test it.

 

[Agile]

Not necessarily do you need somebody else! If you can follow these instructions you may be able to check it yourself.

The actuator motor is the black box on the rear left.

Push gently down on the actuator and pull out the clip which holds the actuator on.

Turn the actuator upside down and push gently on the metal pin in the middle while you get someone to turn hot taps on and off. The motor should push the pin up for CH and retract it for DHW. The resting position is DHW when there is no demand for CH.

If the actuator does not do this either the actuator is failed ( about £40 ) or the PCB or another component is failed.

Use a 12 mm rod of some kind to push the pin in the top of the diverter valve down. With that held down the diverter will be in CH mode and the boiler should operate in CH mode as long as the pin is held down.

Having said all that, I dont think your diverter is the cause of your problem! But it does no harm to check!

Tony Glazier

 

[weargas]

Not necessarily!

To which comment?