Backwash vs Cartridge Clean: Reading Filter PSI on the Route
Filter PSI is the cue. Clean pressure plus 8-10 PSI, it's time. Doesn't matter what day of the week, doesn't matter that you cleaned it three weeks ago. The gauge tells you.
What changes is what you do next, and that depends on the filter on the pad.
DE and sand: backwash on the route
DE and sand filters get backwashed. Multiport to BACKWASH, pump on, run until the sight glass clears, pump off, multiport to RINSE, pump on for 15-20 seconds, pump off, back to FILTER.
On a DE filter, you're not done. You have to charge it back with DE through the skimmer. How much depends on the grid square footage — check the label on the filter or the manual. Skip this step and you're running grids bare, which means DE blowing back into the pool and grids that tear up fast.
Sand filter, you're done after the rinse cycle. Note the clean PSI on the gauge so you have a baseline for next week.
When you write up the stop, log it plain. The customer doesn't need a lecture. Something like: Filter pressure was high so I backwashed. Added DE. Swim ready by 4pm. That's the register. That's what they want to see.
Cartridge: pull and hose
Cartridge filters don't get backwashed. There's no multiport. You shut the pump off, bleed the air relief, pop the band clamp, pull the lid, lift the cartridge out, and hose it down. Top to bottom, between every pleat. If it's loaded with sunscreen, body oil, or algae, it needs a soak — TSP or a dedicated filter cleaner overnight in a bucket. Rinse, let it dry if you can, reinstall, lube the o-ring, button it up, restart, bleed the air.
A cartridge clean is a longer stop. You can't do it in three minutes between accounts. That matters for how you plan the day. If a customer's filter is climbing, you flag the next visit as a longer stop and stage the spare cartridge or the soak bucket on the truck before you leave the house.
Where the route software earns its keep
This is the part nobody talks about. Filter maintenance isn't a chemistry problem — it's a memory and routing problem.
You need to know, walking up to the gate:
- What filter is on this pad (DE / sand / cartridge)
- Square footage and DE charge for the rebuild
- Last backwash or cartridge clean date
- Clean PSI baseline and current readings over the last few visits
- Whether there's a spare cartridge on site or you need to bring one
PoolPilot is built around the truck and the single operator running it. The pre-visit brief on each stop carries the filter type, the last service note, the gate code, and the dog warning. When you log filter PSI week over week, the trend is sitting right there in the stop history, so you're not guessing whether last week was 22 or 25 PSI on the Johnson account.
You note what you did, the customer gets the update in the format they're used to — pool's clean, filter was backwashed, swim ready by whatever time — and the billing for the week catches the cartridge clean as an add-on if that's how you price it.
That's the focus. The solo operator, the truck, the stop. Not a project management suite, not an enterprise dashboard. The pad, the gauge, the cartridge in your hand.
PoolPilot is $30/mo with a 14-day free trial. Run it on your route, see if the filter history and pre-visit brief earn a spot on your phone.