Need to replace all the rads in a customers house but i have an feeling it's a one pipe system because of the valves.They are swedish and are around 30 years old,help appreciated.the valves are in the middle at the bottom of the rads.
http://i425.photobucket.com/albums/pp340/officerdibble6/valvew039.jpg
http://i425.photobucket.com/albums/pp340/officerdibble6/valvew039.jpg