Not my field here but you mentioned she had no hot water on friday is there a common boiler with heat exchanger for the home? did the city have apipe problem causing brown airiated water.

It is an indirect heater - just a stainless steel tank with a cupronickel coil inside it that boiler water is pumped through. AND I pressure tested the coil. The Air is coming from the bloom.

Man, whats going on with the water over there?

you may not be anywhere near flint, but...

I have a low pressure hot water system using radiators and had something similar this year. When I bled it the air coming out smelled like acetylene.

The air coming out of a NORMAL boiler system tends to stink especially what comes out of an expansion tank. This was FAR over and above that.