dirty water from return jets

[bof]

This problem has recurred three times now.
I run my pool with water from the balance tank through the filter and back to the return jets. When the balance tank became low I switched to the main drain. When the motor kicked in a cloud of "dirt" came from the jets, this took about three days to clear. After this I changed from the balance tank to the main drain more often. But if I forget or just get lazy when I have had the main drain off for about a week the ploom occures. Any sugestions on how this occures


Thanks in advance.

 

[mas985]

What is the filter pressure in each "mode"?

I would assume that the balance tank has a much lower water level than the pool?

What is the size/model of your pump?

 

[bof]

Hi
The filter pressure is .75 bar for the main drain and balance tank.
Yes the balance tank water level is lower than the pool even when full.
The pump is a 1kw

 

[mas985]

Then the filter pressure should be higher when on MD vs the balance tank.


My theory is that because the water level is higher for the MD, head loss is lower and flow rates are higher pushing the dirt through the filter. However, that doesn't explain why the dirt is getting pushed through the filter. Sand filters will allow very small debris through the filter normally but it is very small debris (< 40 microns). Did you just get done with SLAM for algae?

 

[bof]

Hi
No did not slam but I did find that if I removed the pump filter lid water would feed into the filter chamber, I assumed that it was coming from the sand filter as all the valves were closed. On further investigation I was able to nip up the nuts on top of the sand filter cover. This seems to have cleared the problem.

Thanks for your help, much appreciated.