HELP! I can't get the radiators to turn off!

[4yearsnosleep]

My radiators are blazing and I can't get them to turn off 😩 I normally have the heating on all the time and adjust the thermostat. Working from home today, so they were set at 19 and when DD went to bed I turned the thermostat down to 16 degrees. The radiators are still blazing, so I turned the thermostat down to 10, then turned off the heating completely. No joy, so I hit the reset button on the boiler and now the light is red Radiators are still blazing. Fault with the control unit or the boiler?!? I can cut the power to the boiler.....I presume this will stop the heating? But will it reignite in the morning when I turn it back on? Boiler is a Potterton Suprima, 14 years old

I'm trying to juggle DD starting school 1/2 days and working from home whilst hubby is deployed. Really the last thing I needed!

Have you tried the reset again?

Sounds like a fault either with the control thermostat or the diverter valve.
Is the hot water from a cylinder? Is it trying to heat that? Try turning that off and see if it stops.
Could just be the valve to sent the heat to the cylinder is stuck sending water to the radiators.