It used to, but I changed that long ago. Like v25z long ago.
I'm on v6f and seeing the same thing. I let the reactor run, and the steam pipes never had more than 10 steam in them. It ran out my ammonia, then I moved back to water and nothing happened. I break the pipe leading to the HP turbine, let it queue up a few hundred steam in the pipe, and connect it and the HP turbine runs.
The only conclusion I have is that the HP turbine is consuming the steam when it is insufficient, and didn't output low pressure fluids. I only tried to recycle ammonia.