Can I use SSR to replace the contactor for a water pump? So that one hour works and one hour is off. Does this work damages SSR?(for example pool purification pump)
Without giving us the motor type, current, and starter type, we can't really answer...
Many pumps have a two stage startup with two contactors one for power, one for start/run capacitor.
This is how my septic tank pump works.
It has a very high start current, so a contactor is a pretty cheap choice. In my pump 3 big SSR's would be required to replace the contactors.
My pump contactor is controlled by a float switch. The float switch does not carry the run current, just the control current for the contactor.
A single, small, SSR could be put in series with the float switch, and control the pump. The actual pump current is still switched by the existing contactors.
In fact I have considered exactly this, because the pump power circuit is what I use to charge the car, and occasionally it trips the breaker when the pump happens to start while the car is charging.