UFH pump delay

[cwr]

I'm pretty sure I read somewhere on here that UFH manifold pumps should have a delay on them when turning on, presumably to prevent it pumping against closed head while the Salus auto balancing valves open? Is that correct, or do the pumps not mind for a short time? The pumps I have are Wilo, and turn on at the same time as the Salus valves.

Would something like this be worth fitting?

 

https://www.ebay.co.uk/itm/393480531697?var=662286957555

[JohnMo]

There can be issue if the pump started and had a closed head, as eventually everything would start to get hot.

 

I assume you are just operating on a single zone.  The auto balancing actuator will have the flow rate quite stable when everything is up and running.  Why not remove one and make that loop manual, set the flow rate the same as it is with the auto balance actuator.  Then there is always an open route for the pump.