Pump 10mm rad pipe.

[AverageHandyman-Sam]

I recently moved into my first home in November 2023, I am just starting out in my DIY as the name suggests but willing to give anything a go and have been successful so far.
Since I moved in 4 rads haven’t worked as they should, some not getting hot at all and others getting partially hot with the flow pipe nice and warm but the go pipe cool and a patchy warm rad suggesting a blockage on the return pipe. I’ve managed to get 2 rads away by cutting out sludge blockages/build up next to the Tee joints at the 22mm and reconnecting them with the slack in the ceiling. Since i’m on 10mm grey microbore no plumber wants to power flush the system but while I have a hole in the ceiling and access to the Tees for the other non working rads i’m thinking I can disconnect the 10mm at the tee and at the rad and try and pump the blockage through.
My question is what can I buy to use to pump this through just 1 length of 10mm grey pipe?
I’ve already looked at the pipes and can’t see a blockage so it must be further down. The pipe runs all the way across the house so would be quite the upheaval to replace it.

 

[Madrab]

Water pressure tester - And use a 10mm to 1/2" reducer and pump through water. I've managed to unblock many a microbore using this method, just watch the other end as it is going to get black and messy when it goes