In message , Scott
writes
Well, if I knew how I would. I have a volt metre, the solenoid has a 4
wire imput and its also heavily sealed.

http://www.potterton.co.uk/products/...ingfisher_MF_I
nstall.pdf

Any ideas?

Measure it at the control module - it has a schematic on top and you can
also gain access to the pins of the connectors

--
geoff