PERSISTANT CLOUDY WATER AT OPENING
After two weeks of a SLAM and some initial water transition from green to murky, there appears to be a sticking point which may be related to proper filtration. The pool has been inspected in all locations and the water chemically maintained properly for the past 2 weeks, yet the water isn’t getting progressively clearer. DE has been used, but really isn’t designed to resolve the heavy amount of suspended material currently in the water. DE is helpful for the finer particles at the end of a SLAM, but has its limitations in this scenario.
All things considered, I would offer the two options below: Expedient or Thorough
NOTE: Owner Option: You’ve done this several times we know, but regardless of which option below you take, you may consider one final validation of the CYA-FC levels and conducting a final OCLT just so you can be 100% confident there are no chemical issues and the pool is retaining FC properly. It doesn’t cost anything but time and is good peace of mind. Totally up to you and your testing confidence.
OPTION A: Expedient Method
- Continue with the SLAM and all associated tasks
- Confirm if the sand level is low and add more as required to ensure it is close to the 6 inches from the top mark.
- Open the MPV to inspect the spider gasket and key diverter assembly. Have a new spider gasket available before-hand as the old one may be damaged or tear when opening.
OPTION B: Thorough Method, (Includes Filter, MPV, and Internal Item Inspection/Maintenance)
** MPV **
- When in the CLOSED position, water should not be able to pass freely thru the IN & OUT MPV ports in either direction. In this case, it was noted that during the deep cleaning process, brown water was seeping out of the skimmer area, presumably from the equipment pad. This would be indicative of a MPV problem, either the spider gasket or the key diverter assembly itself damaged and not completely closing-off those ports. It could also explain why the OP noticed a water gurgling sound as if water was moving somewhere. Water "might" have also been going out thru the WASTE port as I don’t believe that port closes when the handle is in CLOSED (not 100% sure), but there was obviously brown water going back to the skimmer. Usually when a MPV has a suspected defect, there is a visible external leak at the valve itself, or water can be seen flowing out of the WASTE line when the MPV is set to FILTER. In this case, perhaps water was allowed to flow out (backwards) to the skimmer due to a bad spider gasket or key diverter seal. If water is allowed to move into MPV chambers improperly, it could also effect normal filtration. To be sure, I would consider opening the MPV to inspect both the gasket and Key diverter assembly. Keep in mind if this MPV has never been opened since you’ve had the pool, the spider gasket may be stuck and get torn when opening the MPV. I would recommend having a new spider gasket on-hand before starting just in case.
** FILTER **
- A new S244 fitter holds about 300 lbs of sand which (when leveled) should be about 6 inches from the top of the filter. This leaves just enough room for the top diffusor assembly to be installed. During the sand deep cleaning process, it appeared the sand level might be low. Pictures clearly showed the top of the upper diffuser elbow opening, but the sand could not be seen below the waterline. If the sand is low, this certainly could impede proper filtration. The owner has not seen any obvious problems with the filter or sand before, but this is the original sand used by the previous owners. Prior ownership chemical treatment is in question. At this point, I would consider replacing the sand to ensure it’s of good quality with no improper chemicals added, and installed to the proper height/amount.
** INTERNALS **
- Other than possibly a low sand level, there is nothing to indicate there is a problem with the internal parts of the filter (i.e. sand getting into the pool, etc). But at this point, and if changing the sand anyway, I would consider doing a 100% internal inspection everything. Once you remove the sand, carefully remove all internal parts for a serviceability inspection. If the filter, ordinally installed in 2013 by previous owners, has never been opened in the past 7 years since taking ownership of the home, perhaps there is more to this story deep inside the filter and/or with the laterals to explain the poor filtration.
TIP: When adding sand, use the Hayward protective cap to cover the open diffuser elbow pipe. If you don't have it, place a small cup over the opening until you get all the sand in.
Below is a link to the Hayward filter manual with illustrations if it helps.
Hayward Manual
Be sure to let us know how things turn out.
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I haven’t cooked for my poor family since Easter Sunday! Have a great day everyone.
