Crackling noise around filter

ethany

LifeTime Supporter
May 23, 2009
527
Trenton NJ
I don't ever remember hearing this sound before but it sounds like a crackling or crunching noise. Can't tell if it's the pump or filter.

Last season I replaced the sand and laterals in the filter. I was getting a lot of sand in the pool. I still get a little sand, not sure why. I followed the directions to a "T" when refilling.

Anyway any ideas?
 

pooldv

TFP Expert
Platinum Supporter
LifeTime Supporter
Moderator Emeritus
Aug 10, 2012
25,412
FL panhandle
It could be pump cavitation if the suction line is blocked or a valve is closed and the pump is starving for water.
 

ethany

LifeTime Supporter
May 23, 2009
527
Trenton NJ
So I should blow out the suction line? I would have to drop the water level below the skimmer. No valves in suction line. I had to plug main drain years ago because of leak
 

retfr8flyr

Bronze Supporter
May 7, 2017
86
Providence Forge, VA
It could be an air leak on the skimmer line. I have a small one on my pool and if I select the skimmer line, with the multi valve, I will get air bubbles in the pump basket and the filter will sound like it is crackling or has something rattling around in it. If I run the valve on both, skimmer and main drain, or just main drain, then everything is fine.
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
23,932
San Dimas, CA (LA County)
Try this

Shut off the pump. Open the pump lid and remove the basket. Then open the filter air bleed and let it drain backwards. See if any bits of gravel get pushed out into the pump basket. I had a small piece of gravel make its way through the basket once and it sounded awful. I had to pull the motor to discover it.
 

JamesW

TFP Expert
Mar 2, 2011
22,036
Part of the problem is that your pump is too big. Excessive water velocity going through the system can create noise, especially if air is in the water.

What size are the pipes, multiport and filter?