Correct that it won't produce without flow if everything works like it should.
It is supposed to be on a timer that only runs when the pump is already on. If not, the gases can build up and explode if it runs by itself. It won't level your house but it will destroy the SWG, a few feet of pipe and whatever the shrapnel hits. There is a flow switch that acts as a failsafe but TFP does not recommend using that alone to turn the unit off. Manually turn off the unit with the pump and double check the timers still line up when you turn them both back on.
It is supposed to be on a timer that only runs when the pump is already on. If not, the gases can build up and explode if it runs by itself. It won't level your house but it will destroy the SWG, a few feet of pipe and whatever the shrapnel hits. There is a flow switch that acts as a failsafe but TFP does not recommend using that alone to turn the unit off. Manually turn off the unit with the pump and double check the timers still line up when you turn them both back on.