Diffney 2024 (Not Holly Bough)
Quizzes & Puzzles0 min ago
No best answer has yet been selected by senga43. Once a best answer has been selected, it will be shown here.
For more on marking an answer as the "Best Answer", please visit our FAQ.It is is to ensure that there is always a path for water to be pumped around.
In theory, if all the radiators have a thermostatic valve, they can all reach their set temperatures and each valve closes. The pump then has no circuit to pump water around. This could burn the pump out or certainly lead to it failing prematurely.