Rad Valves, TRV's, pump speed

[moosehead]

Not sure if this got on b4

Recently had a system extension during which plumber reveresed the heating system flow- new boiler, cylinder, pump etc. During drain down plumber did not change over valves on the rads. One oro two have old Peglers is the flow on these reversible. The main gurgles come from these rads.
Also TRV's are should these be on flow or return? Have sen conflicting ideas on this forum.
Finally pump speed - 1,2 or 3? 13 rads on system, Spuprima 80 boiler, house over two floors?

Any help appreciated

Tks

 

[doitall]

Thermostatic valve has an arrow or bi-directional valves have 2 arrows, no confusion yet, the water should flow in the direction of the arrow.

pump speed the lowest thats works, or it depends on the system installation, pipe sizes, etc etc etc

 

[moosehead]

Thanks DIA.

When you say 'working' what exaclty do you mean - all radiators and cylinder heating up? Presently they do on pump speed two, I am just concerned re noises from rads and i had also read elsehwere that a reduced flow over the boiler heat exchanger can lead to premature wearing out. If pump speed was too low does this also mean too low flow?