Originally Posted by
rs1987
Well, this isn't a definitive test yet, but prior to reading your reply I set the pump to 70% and the heating partial load back to auto. It hasn't cycled once in one hour. Normally it's done so multiple times by now.
Right now it's keeping the temperature at exactly the set point with the burner on low (looks like 5% at a guess)
The only disadvantage to setting the pump speed higher is that it's clearly increasing my return flow temperature. Measuring on the pipes going directly into and out of the boiler, at a 55 degree flow temp, the return temp is just on 50 degrees, so increasing the flow temp to 60 or above would increase the return temp to above 55 and so the boiler won't work in condensing mode. I can live with a 55 degree flow temp though as the radiators are still pretty warm when fully open.
Is it ok to leave the pump permanently set at 70% - 100% (D.014) ? I'm not going to break anything, right?
EDIT: it has actually cycled now once. The behaviour was a little odd. It kept the burner going even after the temperature went past 55 and got to 59 (despite the flow temp being set at 55). I then got the hourglass cursor and the anti-cycling timer started counting down.
Yes, I balanced them myself. They'd never been balanced obviously as all the lock shields were fully open on all the radiators. The problem was that the two radiators at the extreme opposite ends of the house were not getting warm. Now they're toasty and they all get warm at roughly the same speed when starting from cold.
Because it shows the hourglass cursor on the LCD display and when checking the time on the anti-cycling countdown timer, it's counting down. The heating icon shows as off and the flow temperature reduces slowly by about ten degrees while the hourglass cursor is displayed. If I then go and reset the anti-cycling time, the hourglass cursor goes off, the boiler turns on again and the radiators heat up. Or alternatively if I just wait until the countdown timer hits zero, then the boiler turns on again.