Service wasn’t always such a cinch. Product improvements have made cleaning pools a much more efficient process. However, plenty of veteran service techs remember working on now antiquated equipment. Here, we look back at some of the filter designs that couldn’t quite make it in the modern world.
Bob Blade, owner
Aloha Pool and Spa
Pacific Grove, Calif.
Product: Spin Filter
I used to work on spin filters, and they had their place — a lot of people still kind of like them. But they were the dickens to work on. You had to have all the spares. It was a cast-iron filter with a porcelain lining, like a dishwasher or a pot, but if you had a little nick in the filter, the chlorinated water would just corrode the dickens out of it.
The Swimquip spin DE filter had a green-enameled paint job on it with porcelain-lined cast-iron spin grids, crank assembly, brass rods and a zinc anode, plus a couple of gauges on top of it and a backwash valve.
The closest thing to it may be what’s called the Hayward Perflex, which has been around for 25-30 years. It has spring coils, and you pump the handle up and down. The springs stretch the DE grid cloth, which shakes the DE and dirt off, and then you open the duct valve on the bottom. Spin DE is like you’re shaking all the stuff off the filters. You give it a little rattle or shake when you backwash — it’s the same idea. When you shake it, you’re watching the sightglass on the rotary backwash valve, and you can see it go out. You thread it into the wasteline, and as the water flows through, it diverts or splashes up into this sightglass and you can see the muddy water going through at full force.
They’re popular with aboveground pools. They were problematic, but they would save water — you’d only lose 10 gallons out the waste lines as opposed to 200 or 300.
Bob Nichols, owner
Precision Pool and Spa
Product: Vault Filter
[The Anthony McIntosh filter] was a big concrete vault with a low-head pump. The water was pumped through these canvas bags into the vault and gravity-fed back into the pool. What a nightmare those things were. They were [installed] in the ’70s, but they were still around in the ’80s. Most technicians would walk in and say, “No thanks.”
Cleaning the bags was impossible — you had to soak them and hose them. They were just terrible. We used to call the vault a casket. It’s sitting there with a cover on there in the dark, getting nice and warm. There aren’t any ultraviolet rays getting in, so you’d open that casket up and there’d be more algae in there than the whole neighborhood.
It was a weekly thing — you had to take those bags out, clean them and bleach them every week. You’d get algae spores in the casket, and they’d dribble right on down into the pool — you’d just watch the algae come back through the return line. It was a total nightmare.
Bob Nichols, owner
Precision Pool and Spa
Product: Cast-Iron Filter Case
It had about 20 bolts around the edges, and it looked like a Naval mine. Somebody, I think it was Swimquip, used that old sand filter tank and turned it into a grid tank, but there were still 20 bolts along the edge. And those were the days when filter servicing was usually included in your pool service bill. A lot of guys just siliconed them together and just finger-tightened the bolts.
It’s a very popular filter, but lots of people had their head busted on them with the flying lid. Most pool filters are 2-inch piping, and some are 1.5. This one was custom-made with 2.5-inch copper piping, which is popular today (a lot of pool filters are starting to have bigger pipes). It would handle the 110-125 gpm flow rate that was required for that size of pool then. It’s got real thick stainless steel construction, like older cars that had thicker fenders. It’s ugly as sin, but it’s still serviceable — it doesn’t leak.
The parts on it are still good. I put on Jandy valves (3-way) instead of gate valves, so you can backwash it. So I just simplified it. It’s still in service, and will still be running 50 years from now. Plus it meets the modern flow rates, so it’s a good little DE filter.