We built a new house. The plumber did not put the plugs in any of our Delta rough in valves for the tub/showers. The well shock was done which contains heavy amounts of chlorine...this project has taken a while and by the time we opened up the valves to work on the bathroom finish plumbing (our hired plumbers were no longer working for us) we saw that the rough in valve was corroded from the water sitting in it, due to the plug not being inserted to protect it from water sitting in there. We looked up how to clean it and used vinegar and baking soda. Hoping that would be ok, we put the cartridge in and put the faucets together. It felt pretty smooth inside although not like a new one, which feels like glass. We put grease on the o-rings. None of our tub faucets will provide hot water...it gets warm...but not hot. Could it be that the corrosion ruined the ports where to o-rings sit? I certainly hope not because that will require us cutting into all of the walls for the three bathrooms. Another thing that is puzzling is that when we shut off the water lines and turn only the hot line on and turn on the tub faucet, no water comes out. What is going on? This new house has been a living nightmare.