pipes vibrating and making a noise but boiler is off

[LOLLA]

Please does anyone know why the pipes would be making noise and vibrating heavily even though the boiler is switched off at the mains. The boiler is not working and we have no heating yet the pipes are vibrating.

 

[Baxmax]

Earthquake .

 

[Corgigrouch]

Is it a combi and if so, what is the reading on the pressure gauge?

 

[LOLLA]

No its a conventional boiler Gloworm Micron 40FF.

 

[Corgigrouch]

RATS.. That has blown a hole through my idea

Is it a constant vibration or only at certain times...Strange as it sounds could it be road traffic shaking your house?

 

[LOLLA]

... no its constant. It sounds like someone drilling ......i am sure its not road traffic.

 

[Corgigrouch]

If the system is switched off, then unless some fool has wired the pump to run independently of the heating (Very unlikely) the only thing that I can think of that could cause a vibration in the pipe work could either be a leak somewhere causing the valve in the F&E tank to open slightly and the pressure of the water passing through to cause the valve to resonate or possibly a damaged coil in the hot water cylinder resonating rather like a reed on a clarinet as water passes from one water circuit to another.. have you noticed any over flows dripping at all? Sorry for such a tenuous thought but it is all that I can think of at the moment

 

[LOLLA]

...This noise started a few weeks ago after our 3 port valve was changed by an incompetent engineer from Glowarn. Our overflow was leaking heavily soon after but a new plumber found that it was because the F & E tank lid was faulty and was leaning on the ball valve causing it to overflow The lid was changed and the leak stopped. Funny enough the noise remains the same.

 

[heatingman]

I,m intrigued, how/when/can you stop the vibration?

 

[LOLLA]

..it stops by itself after about 10min....

 

[Gasguru]

.........but a new plumber found that it was because the F & E tank lid was faulty and was leaning on the ball valve

This can't happen if the float valve has been set at the correct level. The water level should be about 50mm above the feed pipe outlet to the system (with the system COLD).

You never did post a picture of the INSIDES of the tank. It wouldn't surprise me if the float valve has not be adjusted/bent down in the past (or even now) and the result is serious corrosion to the system and a feed tank full of sludge.

Temporarily turn off the mains stopcock and see if the noise stops.

 

[corgiman]

sounds like some pipes have moved off their clips and the noise is being caused by the pump over run

is there anywhere where the noise is louder? or is it all over the house

 

[heatingman]

Does the system have thermostatic rad valves. I think you said you have a 3port/mid-position valve?

 

[Corgigrouch]

You mean that it stops ten mins after the heating is switched off? and the heating is still hot? or will it do the same if you run the heating for a min or two and then switch off where it will all be cold still? I'm thinking along the lines of contracting water flowing slightly and causing a valve to vibrate..

 

[heatingman]

another question.
After the ten mins and the noise has stopped do you have to re-set/re-start anything to get the boiler/heating running again?