Bad radiators

Now this looks worse than it is!!!

Our house is only 2.5 years old and this is the colour of the water that came out of the radiators today when I bled one (on advice of a plumber!) before switching on the heating for the first time today - it was that cold.....!!!

Anyone know if it is normal? Apparently they might not have been flushed through when the system was installed....even had some metal filings in it. Email is off to the builders first thing just in case!

We had parents evening tonight for Hannah and it turns out we have a child genius!!! (Actually I think we knew that :-) ) I won't bore you with any details except to,say she is doing very well indeed - clever girl!