Vaillant boiler not heating water

[AGAS]

We first of all had no display and with friends help changed the fuses in the circuit board which got the boiler up and running!

We've had my other halfs brother out and he had a look inside and said it all seems to be in working order from what he can tell

so it wasn't running then . an answer to your problem is only as good as the information provided

 

[aptsys]

Whatever, but no way is it 100 hertz. 1 full hertz has a positive and negative trace, so 50 hertz can never be 100 hertz.

 

[DP]

Aptsys, Thank you for the screenshot
100 changes a second is not the point of the argument, what is in disagreement is the term Hz to define the hum
The 50 herts ac will be a sine wave, 100 changes per second will not be a sine wave as there will be other 'noise' components within the hum frequency spectrum
I would love to copy the trace of this off a scope but do not have the drive nor the test components to produce the trace of the hum, nor to argue the toss with certain person who posts and cannot back up with solid information

Once more thank you for taking the time to do the research and posting the results

 

[bernardgreen]

When you are listening to a sound produced by a magnetic field you get two pulses per cycle when it is the effect of the strength and not the polarity of the field.

Feeding 50 Hz AC into an electromagnet will vibrate a bit of metal close to the electro magnet at 100 vibrations per second. The metal moves towards the electromagnet irrespective of the polarity of the magnet fields pulses.

If the bit of metal is one end of a magnet then it will be vibrated at 50 vibrations a second as it will move towards the electromagnet on one polarity of the magnetic field and move away from the electromagnet on the opposite polarity. ( like poles repel, opposites attract )

Feeding raw DC ( full wave rectified AC without smoothing ) to the electromagnet will create100 magnetic pulse per second and these will all be the same polarity so vibrations will be 100 per second

 

[Agile]

100 changes a second is not the point of the argument, what is in disagreement is the term Hz to define the hum

The 50 herts ac will be a sine wave, 100 changes per second will not be a sine wave as there will be other 'noise' components within the hum frequency spectrum

Frequencies are still described as Hz regardless of if they are sinewave or square wave or any other waveform with a repeating pattern.

 

[DP]

A tomatoe soupe is made of other ingredients too, but tomatoe soupe is the generic term telling a person tomatoe is the main ingredient. Similarly, the 'noise', which is the hum, will have many other components of which 100 pulses per second will be a foundation part

You regularly berate people for not being exact and precise and need for very careful measurements, yet you make a comment that is only half truth or even fraction of that. Clearly you have rudiments of what is happening but you lack in depth knowledge of what the hum is. Unless you can demonstrate or point me to a source that says hum is 100 pulses per second nothing more nothing less you have no argument. If you can, not only will I thank you for informative text, it will also restore in my eyes, make me see you as a person who has aforementioned traits you regularly ask for.

Cannot be fairer than that

Note. Have not been nasty, rude, or offensive.