ajs heating

>mixed bunch and I could not tell which were Lockshield and which were on/off types

their is no difference between a lockshield and a wheelhead valve only the plastic cap.

>(about 1 turn open on the Lockshields)

thats all you need, a fully open valve is only about two turns any more after that and it doesn't restrict the bore if you look down a valve.

their is useally aprox 11 degrees difference between your flow pipe and return.