6°C, becoming greyer but still dry.
Much as I hate DIY plumbing, this one job has to be done. The kitchen radiator has left little puddles beneath when I get home. The system pressure would drop enough to shut down the boiler by the end of the the week.
After trying loosening and re-tightening the nuts on the valve for no improvement, I bought a replacement valve. This is a basic thermostatic valve and looked like the right size to fit onto the same nuts and olives.
Now that the heating system is a closed loop combi-boiler, draining didn’t take long.
The pipe looks scruffy but I can clean it up when I decorate. Perhaps Emery paper then varnish it to keep the copper colour.
Cost of repair? Just over £6.50. Boom!
At the same time, I have put together an emergency pipe repair kit: some pipe, compression joints, PTFE tape and a pipe cutter. Oh and a flexible pipe, that should be enough should the worst happen this winter.