Nigel, Is that what I am seeing to the right of the unloader?
thats it Trae,....... I had my manufacturer install one on my hot water unit before shipping after reading literature on general pump website, then Alkota releases this video about 9 months ago showing its function on a machine, not sure what type of pw unit it is.
http://www.youtube.com/watch?v=xkHMZAq-kxg