Central heating

At last the engineer has agreed there must be a leak! After pulling up floorboards he now agrees with me that it's a single not double pipe system.
Why is that men will never believe that a woman can know about these things?
Now I have to wait until he can fit me in to re pipe the house with a double pipe system. This may not be til after C********* when it will take over a week.
Not a happy bunny!