How to Break Down and Service a Purex-Triton Nautilus FNS DE Filter
Servicing DE Filters
It is recommended that DE filters be dismantled and inspected at least once per year— ideally, every 6 months to prevent DE powder "blow-back." Blow-back occurs when a filter is back washed, DE is then added, and most, or all of the DE, ends up in the pool rather than coating the grids and staying in the filter. This can be caused by a number of reasons:
- Build up: Too much DE can build up over time and back-washing no longer pushes the old DE off of the filter grids when the flow is reversed during the back-wash cycle.
- Torn Grids: When a filter grid is torn, DE powder will escape through the tear. Very minor tears will still allow the filter to hold DE. Normally when a minor tear in a grid happens, It's usually not long after that other grids begin to tear as well. Although individual grids can be purchased, It's recommended to replace to replace the entire set.
- Manifold: The manifold on the top of the grid assembly directs flow through the grids. These can crack and allow most, if not all of the DE powder to blow back into the pool. In this case, the manifold will need to be replaced.
Dismantling the Filter
Be sure the pool pump won't come on. Shut timer off, or "service mode" in automated systems. Service mode isn't usually accessible from the remote. Will need to execute service mode from the outside control panel.
Remove the Drain Plug
Remove the 2 Side Bolts
Remove the Lid
Rinse the Tank Out
Cleaning the Grid Assembly
There's no need for using any harsh chemicals to clean the filter grids. Just rinse the grids with a good jet nozzle on the hose. Do NOT take the grid assembly apart unless you like puzzles. Can be a bit of a hassle to re-assemble. When the grid assembly is clean it will need inspected. Look for cracks on the Manifold (top large plastic piece that holds the grid assembly together) Also be sure to inspect the grids themselves and look for rips or tears in the material.
Clean the Grids
Re-Assembling the Filter
There is an inner metal ring on the inside perimeter of the lower half of the filter, the split point. The rubber o-ring is wrapped around this metal ring. Remove both from the filter and rinse clean both the metal ring and o-ring. Rinse the split point on the filter housing of any loose debris.
O-Ring and Inner Metal Ring
Replace the Grid Assembly
Before Replacing the Lid
Make sure that the o-ring is lubricated with a sealant/lubricant specifically designed and manufactured for swimming pool equipment. Set the lid on and turn lid slightly right and left to set the lid well into the lubricated o-ring. Replace the band clamp and tighten both bolts on each side of the filter housing. Replace the drain plug on the back of the filter. Close air relief valve.
Clean Filter Pressure
© 2018 Rob Hampton