intermittent resonating sound like a tuning fork

[monkswales]

Hope someone can help me solve a frustrating problem that is causing me to lose sleep. We have lived in our rented accommodation now for 8 weeks. For the past 6 weeks we have been hearing a resonating/humming noise that only lasts for between 10-30 seconds but is loud enough and annoying enough to wake us up. When we hear the noise we can hear it loudest upstairs - sounds as if its in between the walls. At first we thought it might be the cowl on the chimney but this has been replaced and we are still hearing the noise. The boiler is in the garage directly below our bedroom and as it almost sounds like some sort of pump trying to start up but not being successful we thought this might be the source but as we also hear the noise when the boiler is off this rules this one out. Does anyone know if there is anything associated with a heating system that could be making this sound even when the boiler is off? Its so frustrating hearing the noise but not being able to locate it and then solve it. Any thoughts really appreciated
Thanks

 

[picasso]

Run a hot tap for a few minutes if that stops the noise if it does the change the ballcock in the loft (if you have tanks in the loft) if not try flushing the toilets and see if that is the problem.

 

[monkswales]

Thank you...will try that but which tap should I turn off? The noise does not last for that long so I would nt have much time to flush toilets or turn on the taps . Is it an easy job to change the ballcock? That sounds like a good start.
Thanks for taking the time to reply.

 

[Newboy]

If you're in rented accom then refer the issue to your landlord - apart from the fact you're paying rent you shouldn't be undertaking repairs

 

[monkswales]

Indeed we are in rented accommodation and as such should not attempt repairs however the kanlord has already paid to have the chimney cowl replaced on our initial thoughts that it might be this causing the noise. We are reluctant to ask him to now get a plumber out in case it's not that either . If it's a simple enough job, just like changing a washer then we just thought we would get on with it and try and sort it ourselves. However if it's a more complex job with risk of something going strong then we would most certainly need to contact the landlord and ask him to arrange a plumber's visit.
Thanks for your reply.

 

[polesapart]

Switch off the electrical supply to the boiler and boiler controls overnight just to completely eliminate it from the equation.