Adding cleaner to radiators

Hi All,

I want to check the following - had an overflow pipe which was constantly dripping I investigated small tank the HW one and the ball cock was slightly too large the tank so I did a work around stretching the tank with a piece of wood and it did the job.

The water was absolutely filty and full of rust. I have another radiator which is continually requiring to be bleed and the one next to it some previous house owner rung off the bleeding nut so I will have to replace this.

I did notice there is another overflow pipe to the front of the house which is continually dripping also.

When I get the radiator replaced I presume the system would benifit from a power flush - its a hard water area which I suppose wont help?

Thanks

Dave