baxi 552 noise

[bush1207]

Hi there i am pulling my hair out with this one i have a baxi 552 boile

the problem is i have 2 pipes run down the side of my fire place the make an awfull almost like kettling sound at anytime of the day, th heating does not have to be on for these to go off. I have drained th system, bled the radiators and also treated the system with fernox. th other pipes ie under the floorboards are fine and make no noise what s ever it is only the 2 that run down beside my fireplace. I have had a engineer come out and service the fire and he said that it was trape air in the system. I would be very greatfull to anyone with som suggestions on this case thank

-- bush1207

[Mr Fixit]

I have a Baxi boiler that has a pump over run , which runs the pump after the boiler goes off to stop it overheating when the boiler cools off then the pump stops , but mine presently has a faulty circuit board and the pump runs continuous even though the heating and water are switched off could this be the same fault

[Ed Sirett]

I wonder if you have gravity HW? As time goes on the thermostats on these models get less sensitive and the running temp may have increased. Try turning the boiler thermostat down and see if things still work. A product that may help is the Boiler Noise reducer (by fernox and IIRC Sentinel do they version) this is distinct from the X100 or MB1 inhibitor which often goes by the name "fernox". At the least the noise reducer will change the kettling to dull thuds.

If the system is working for heating and HW then I doubt that trapped air is a problem, otherwise trapped air could be the cause.

HTH