[jimbo2012]

The issue here seems to be is bleach safe to use.

Obviously hot water is fine it is used through out the house draining thru your PVC pipes, I did a search (after Bill explain how the system works offline, tks)

It is fine as per;
While PVC is incompatible with many organic solvents, it has good corrosion resistance and is compatible with most common mineral acids and bases. You already know, for example, that pouring drain opener down your drain does not damage your PVC pipe, and drain opener contains sodium hydroxide a stronger base than the sodium hypochlorite in your bleach. Unlike sodium hydroxide, sodium hypochlorite is also an oxidizing agent, but PVC is nonetheless resistant to sodium hypochlorite as well.

Compatibility

PVC has excellent chemical compatibility with common household bleach brands, such as Chlorox. It is resistant to solutions of potassium, sodium and calcium hypochlorite, all of which are used in various types of bleach