What is this system?

[MikeAustin]

I am having problems that may stem from old pipework. Before I had a new boiler installed in 2005, I took a picture of the old pump(s) and associated piping:
View media item 10670Any idea what sort of system this was? What is the chunky brass thing in the CH pipe?

 

[namsag]

SMC controller system . The big brass thing is a none return valve

 

[MikeAustin]

SMC controller system . The big brass thing is a none return valve

More questions! The upstream pump has two outputs. Are they controlled electrically? Why would there be another pump downstream? With two pumps, would an NRV be necessary? I don't think there is any gravity head downstream. Is that another sort of NRV in the HW pipe?

 

[namsag]

www.gasman.fsbusiness.co.uk/fully_pumped_systems.htm

explains it

 

[MikeAustin]

www.gasman.fsbusiness.co.uk/fully_pumped_systems.htm

explains it

Great. That explains everything - even the results of not having an nrv in your forum id.

 

[doitall]

Except the non return valve is in the hw flow, and the brass thing in the heating is an upside down filter.

 

[swbjackson]

Looks like it could be one of those NRVs with a ball that rises up out of the way.