Hartley Wintney is a twelve-mile run east from the Basingstoke base, straight along the A30 through Hook, which keeps it comfortably inside the regular working patch alongside the rest of RG27. It is a village with a genuinely distinctive housing mix, and that is what dictates the work rather than any generic idea of a Hampshire village.
The conservation area around the High Street and the cricket green holds Georgian and Victorian property, listed frontages and a run of older cottages, many with solid walls, chimney stacks in awkward places and no realistic route for a modern flue on the visible elevation. Behind that sit the twentieth-century additions along Fleet Road and Church Lane, and then substantial detached houses on the edges toward Phoenix Green and Winchfield, several of which run unvented mains-pressure cylinders, multiple bathrooms and heating loads that a small combi was never going to satisfy.
That range means the sensible answer in Hartley Wintney is genuinely property-specific. A system boiler and unvented cylinder is often right for the larger houses, a well-specified combi for the smaller cottages, and air conditioning increasingly makes sense in loft conversions and garden offices where insulation was upgraded without any thought given to summer. All of it comes from one engineer holding both Gas Safe 593588 and F-Gas Refcom REF1025590, which avoids the usual argument between two trades over the same wall.