Radiator Blues

[Lord Panda]

One of my radiators has just sprung a small leak from a very tiny hole right at the top, in the middle of the bit that faces out. I have tried to plug it using metal sealant, but to no avail. I don't want to replace it as my home is on the market, but is this the only realistic option and how much can I expect to pay?

[compo]

There's some stuff you can get from plumbers merchants called Fennox Super Concentrated Leak Sealer. You actually put it into the system and it works like a repair fluid for car radiators. Might be worth a try if the hole is so small.