This issue has been fixed for OS 1.8.0. If you can't update versions, you can use this code in a measure and run via Apply Measure Now to hook up the coils programatically.

model.getAirTerminalSingleDuctParallelPIUReheats.each do |piu|
reheat_coil = piu.reheatCoil
  if reheat_coil.to_CoilHeatingWater.is_initialized
    loop.addDemandBranchForComponent(reheat_coil)
  end
end