I've been having this problem for the past 2.5 years and no one was able to pin point the problem.
9/10 times on warm day,evening time, my cooktop in the kitchen has no gas supply, we have to wait till dark, take a normal hot shower, then the cooktop will start working again.
we have the builder come in and inspect the issue, but he said nothing can be done unless it happens in front of him and they wouldn't come in after 5pm.
any idea? i have been having dinner after shower almost everyday for the past 2.5years.