New Vailant boiler fitted - Should I replace old radiators?

I'd say the radiators are 20/25 years old. When taken-off, black dirt came out of them.

Should I replace them, or can I clean them out somehow?

I had the boiler working for a short time but am concerned that the sludge may damage the boiler.

Have taken all of the rads off to decorate. I've got a plumber coming on Saturday to fit a new bathroom so somethign he can do?

Also, should I replace all of the valves, please?

Thank-you in advance.

who fitted the boiler? its the installers responsibility to make sure the boiler is connected to a clean system whatever that involves. Old rads can be cleaned, best you can do as a DIYer imo is remove them and flush them out in the garden.

It would be best to replace as new is always better. How many radiators do you have as you can get a power flush but as far as I know is normally around £550 (BG). Might work out cheaper replacing if you ar handy puttng them on. Best wait to see what anyone else says though.

After flushing the rads you could fit a TF1 or Magnaclean filter on the return to catch any further dirt.