Worked a treat bud. Amazing how much softer they are after a quick blast of heat, I was shocked, could easily bend it in my hand but was rock solid before.

Feel like I wasted a small fortune buying new coppers when I could probably have just reannealed them all, wouldn't have been as bufty though

Unlucky re the pump, £100 for a new one isn't it? Managed to kill my very low mileage Bosch pump this weekend too, you can hear it trying to spin up, but just clicks away.