Danfoss has made improvements to its ranges of direct-operated solenoid
valves: the compact 'A' system and slightly larger 'B' system. Suitable
for pipes up to 1in diameter, both types have 3/2 way versions (for use
with pilot valves) and 2/2 way versions for a broad range of
applications. 'A' valves now offer greater long term reliability, while
'B' valves offer a wider choice of sealing options and orifice sizes.