Fernox additive problems- help ?

[alancleff]

Moved into house 10 months ago - I have a Baxi wall boiler 10 years old and 10 rads all in 10 mm pipe- open system with header tank in attic, storage tank and pump in first floor airing cupboard - all normal all ok and system had record of fernox already added a year ago. I decided to drain system to add a rad and added normal fernox additive to protect the system at the same time got all the gundge out of the header tank. All ok but the boiler was now noisy whilst it is working - ie flame is on. Decide to add Fernox boiler noise reducer - peace, for 2 days BUT now when the boiler has its flame on, the piping around the pump and the storage tank start to vibrate fairly loudly after the boiler flame has been on for about 10 mins. If the room stat cuts in and the boiler flame stops all is quite - as the flame starts agian so does the noise ? It sounds like the pump could be cavitating ? - if I turn the pump flow down the noise turns to a very loud throbbing - does Fernox noise reducer lower the boiling point of water ? If I dilute the water in the system will it help ?

Any advice welcome - thank you

HELP PLEASE !

 

[weargas]

how many header tanks do you have?

 

[weargas]

If I dilute the water in the system will it help ?

ha ha
with what?
water???
eeydyut

 

[alancleff]

how many header tanks do you have?

I only have the one header tank and all the rads are bled fine but the noise sounds like the a boat prpeller noise but only when the boiler is firing - the pump works fine on its own and the noise only ocures when the pump is running AND the boiler is firing - I was thinking that the amount of Fernox silencer additive could cause the problem by reducing the boiling point and therefore diluting the mix might reduce the effect ?

 

[kevplumb]

does it say primatic or single feed on the cylinder

 

[alancleff]

does it say primatic or single feed on the cylinder

Sorry I dont know how to tell the difference ?

 

[Bahco]

Near the top of the cylinder if it is a primatic it will be embossed writing and says Primatic cylinder, (if I remember rightly ,I took one out 2 months ago).
If you have added chemicals to a Primatic and the air bubble inside has blown you will have to seek professional help as your hot water will be contaminated

 

[kevplumb]

is that why it says on the packet/bottle not suitable for single feed / primatic systems etc

 

[Bahco]

Hi Kev

 

[kevplumb]

alright marra