Loud vibration when upstairs rads turned on.

Hi,

Have been experiencing noise problems with gch system over past couple of weeks. New house. We have a volkera mynute boiler feeding 4 rads upstairs and 3 downstarirs. There is a wall mounted thermostat upstairs and another downstairs.

Whenever the boiler is on to heat the rads and the upstairs thermostat is set to anything above zero a loud vibration can be heard from one of 3 blue boxes fitted to the pipes leading to the hot water tank in the hotpress. The vibration stops as soon as the upstairs thermostat is turned to zero or the heating is turned off.

What exactly are the blue boxes on the pipes in the hotpress? Surely the extremely loud vibration is indicative of a fault? The noise is loud enough to wake you up if the timer is set to turn on the heating early in the morning.

Does anyone have any ideas?

Thanks

Sounds like 'water hammer' to me, talk to the guy who commissioned the system for a way to resolve it.

Thanks for the reply. I'm not sure if it's water hammer as you suggest. I'm going to try bleeding the rads to see if trapped air is the problem.

i bought a house in 1994 and my oil heating has been brilliant but i got it serviced recently and he really did take out quite a lot of dirt and changed the wick but since he has done this the amount of fumes about the kitchen has been unbelieveable its really unbearable maybe someone would give me some incite as to know why this is happening p.s. the burner is under the work top of my kitchen not outside in the garden