Part No. 40003916-003
For V4073A 5 wire mid-position (3 port) valves. Including:
Honeywell motorised valves made before 1987 will also require a 40003918-007 conversion kit.
Valves made after 1987 can be identified by a bump on the top of the powerhead (see picture).
British gas no. 378454
Compatible V4073A Powerhead