More likely you fixed a leak somewhere, making the system tighter. You now have water hammer that occures at the end of the fill.
You can pick up a fill valve that shuts off a little smoother. I like the Korky MP for that.
We have two bathrooms, first floor and second floor bathroom. After the first floor bathroom tank fills up after every flush, I hear one big thud. I don't hear this thud when the second floor bathroom tank fills up after every flush, I only hear this happening in the first floor bathroom. I noticed this happening after doing a renovation in the second floor bathroom.
How can I fix this problem?
Do you think this happened after shutting the main water valve a few times where the water pressure changed in the first floor bathroom and causing the pipes to make a thud sound?
So you guys think it's not air in the line causing this.
"Air in the line" is code for somebody asked a handyman what the problem was, and having never worked on plumbing said the first thing that came to mind.
Air in the line has got to be the biggest urban legend in plumbing ever.
As soon as you use a faucet, any air from having been drained down quckly comes out. You would have to shut off and drain the home down for thirty minutes got get air in the pipes. Once the water is turned back on, and you use the plumbing; all the air escapes. Even air chambers get waterlogged. And air chambers are meant to cure water hammer, not make it worse.
When all the leaks are fixed on a home, the water has no place to go when something shuts off quickly. In a new home with a check valve at the water meter, we would be installing hammer arrestors at the washer, dishwasher, and the icemaker. All of these have quick closing solonoid valves.