Blimey that’s hot, you have small rads? Or are you letting it cool right down overnight and during the day?
1930s detached house, double glazed, 30cm insulation in the roof, nothing in the walla. A couple of radiators are maybe too small.
House thermostat set at 21c, we both wfh so it’s set at 21c from 7.30am until 9pm, at night it’s allowed to cool to whatever it cools to, but so far has not gone below 16c
The flow was fine at 68c until this recent cold snap, but in this cold the house won’t go above 20c,so had to increase flow temp