Alright! Now it’s time to take care of that filter. Be prepared, as it may be a bit nasty in there. Keep your filter owner’s manual handy and follow its procedures for disassembly, reassembly, and maintenance. If you don’t have it, here is one of Pentair’s manuals:
http://www.pentairpool.com/pdfs/sandfiltersysgenericOM.pdf
Here are also a few of my own tips/reminders:
- Take a pic of your filter and multiport valve just as it is before removing so you remember what position to reinstall it.
- Always turn the multiport valve in the same direction whenever you move it to a new setting.
- Use care when removing the valve, retaining collar, vertical stand-pipe, and laterals (fingers) to avoid breakage.
- Use care when manually scooping-out any “goo” and using your Shop-Vac as to not damage anything inside the filter; be very careful whenever handling those laterals/fingers at the bottom.
- Once everything has been removed/cleaned, and you have reinstalled the laterals/vertical stand-pipe, reinstall the filter’s drain plug and fill about halfway with water BEFORE pouring-in the sand. This is to protect the laterals from breaking under the weight of the sand as you pour it in.
- You should have a stand-pipe cover (sand guide) to keep sand from going down into that pipe when adding sand. If you don’t have the factory one, an old soda can (with one end cut-off) should work fine.
- Slowly begin filling with sand. Ensure to keep the stand-pipe straight and centered as you fill.
- Continue to add sand to the recommended level (probably somewhere around ¾ of the way)
- Remove the stand-pipe cover/sand guide.
- Make sure to clean the top of the filter to remove any debris, sand etc before reassembly. If you have an O-ring at the top for your multiport vale, now is the time to lube it with some silicone-based pool lube (i.e. Magic Lube). Do NOT use any petroleum-based household lubricants like WD-40, Vaseline, etc.
- Perform an initial backwash (about 3 minutes) and thorough rinse (at least 30 seconds or more until clear) before setting the selection valve back to filter mode.
Once you have completed the filter cleaning and the system is operating again like normal without leaks, let me know. I want to go over some
Poolmath calculator stuff before we start adjusting CYA and FC to ensure you receive the expected results. I’ll be watching for your update.
If you've never opening that thing up before, now would be a good time to check the owners manual and/or look at some YouTube videos in advance so you know what the laterals and center stand-off pipe are like.
So in the mean time I will be reading lots more about what to do or not to do!