In the catacombs part 2

The condensatesystem as I said in my yesterdays Blip is partly located in the catacombs of unit EC 20.
Here is a view at the two most important things in the system; the condensatepumps. One is always running, the other one is a 100% standby pump.
The pump that is running allways has speed regulation, so the revolutions per minute can be varied and so the delivery (output) is variable.
This regulation has been fitted later, before that both pumps had a fixed rotating speed.
When this pump is started it goes very smooth.
When the other one starts, it goes with a tremendous bang, especially when the system is not de-aerated properly.
In 1976, when the unit was in newbuilding phase and testing, the system did not have enough venting valves, so some airpockets were still inside the piping instead of water..
Painters who were painting the pipes at that time were accidentely not warned when the system started and jumped in panic from the scaffolding and ran away in distress because the pipes were swinging more than 50 cm to each side....