Those are some great answers. Note we’ve not had a repeat yet. I’m concerned we will. It’s expensive to have the plant stopped.
1st response.... I’ve reviewed that 60 plus page article..thanks.
3rd response Fittings. Yes. I want the early start guy to check carefully around the pump before starting. Will do this tomorrow and Accept as you’ve indicated it could be such a small leak it won’t show/ it will suck air.
2nd response.....You need to look at the route of the pipes in section.
Where was this "air bleed"?? Good point... it’s the air bleed at the Grundfos pump itself. I was only getting the tiniest amount of air out then the pump would try to go again and build pressure before dropping again.
What do you mean by "blame the PVC pipes"? I’ll attempt to put an image up. The installer wants to change to steel. I can’t see this as the problem as indicated.
You also need to look at velocity. If you can get to >1m/sec then you can normally sweep air bubbles out of pipe, even vertically down. Less than that and it could struggle to sweep air out. We move 4000lph through a PVC pipe with an I.d. That looks to be about 50mm.
Is this a closed system? No, it’s an open tank system.
No real details here so very difficult to fault find from afar. I’m so aware of this and tried.... I see the holes in my report
thanks all for responding.
Image... the upper run of pipe with open valve goes to chiller pump 30ft or so below. I cracked open that valve you see elbowed down for the hell of it wishing it was at the upper most spot in line. Will have a valve installed if we have a repeat. The lower run of pipe goes to a chiller and returns to the right tank to give us coolest water. There are 3 and the left one receives the warm return water.
We won’t go into why there are 3 tanks and all the connections. Let’s just say it’s an improvement on what was there before. The suspicion is we developed the air problem 1 week after the changes you see.
The previous system was quite strange. 3 x 1000 litre tanks all open at bottom to the pump we are discussing 30 ft below. The 3 tanks were unconnected and had ball valves on return flow from chiller. We would end up with alternate tanks throughout the day taking charge of releasing water. The other 2 could be seen to have the ball valve closed and obviously not releasing.
The change was to connect the 3 tanks. They have pipes running between them you can’t see. They are now a single body of water and flow nicely. Added bonus was finding we can nicely control main warm return from cooling tower to chiller 1. Chiller 2 now sits with its own 3000 litre single tank in reserve. It’s set to kick in within .5 degree warming and circulates it body of water through the middle tank you see that’s off. It’s a nice setup because the middle tank circulates into both the warm return water and chilled outlet water. Provides a gradual steadying to desired temp.
