VIESSMANN VITODENS 100 COMBI/CONDENSOR - NO HOT WATER

[dawson6777]

Central heating is working fine, but now no hot water at all. Last week the hot water temp was up and down, but now I can't even here the boiler firing up on demand. Any ideas?

Dawson

 

[Agile]

CH off, does boiler fire up or make a noise if DHW is used? If so then diverter valve problem.

CH off and no noise from boiler if DHW is used. Then DHW flow switch problem.

Useful to know which model of boiler!

Tony

 

[dawson6777]

CH off, does boiler fire up or make a noise if DHW is used? If so then diverter valve problem.

CH off and no noise from boiler if DHW is used. Then DHW flow switch problem.

Useful to know which model of boiler!

Tony

Hi, Type wb1a. Central heating off, no noise from boiler.

Thanks, Dawson

 

[Agile]

Well now you know what the fault is likely to be!

Tony

 

[mysteryman]

Look for the obvious things. Is it showing a tap symbol when a tap is running? No probably means the domestic flowswitch is stuck off, usually a bit of debris in it from the cold main. Yes probably means the diverter valve stuck in the central heating position. The boiler proper is OK or you wouldn't get central heating. Is the tap knob in a working position?

 

[dawson6777]

Look for the obvious things. Is it showing a tap symbol when a tap is running? No probably means the domestic flowswitch is stuck off, usually a bit of debris in it from the cold main. Yes probably means the diverter valve stuck in the central heating position. The boiler proper is OK or you wouldn't get central heating. Is the tap knob in a working position?

All sorted thanks. Found the pipe which carries the flow switch gummed up with black deposits. I cleaned this out plus the heat exchanger and all is fine.

Thanks to everyone.

 

[Agile]

Another happy DIYer!

I would have charged £84 to sort that out for a local customer!

Tony