Multiport valves are the main water route interchange for your pool water. If the water needs to be forwarded, reversed or drained out, it will need to be done through this valve. The routing system inside a multiport valve is essentially water’s equivalent to chutes and ladders.
These valves have as many as seven “positions” but for the most part the average pool owner will only use a handful of these. Here is a list and explanation of the most often used positions so we have a solid footing moving forward:
- Filter – The standard operation mode; the water is cycled from the pump through the filter media and back to the pool.
- Backwash – This selection is the cleaning cycle. The flow of the water is brought in from the pump then routed to enter the filter reverse to the normal direction. This effectively begins to loosen and eventually eject dirt through the waste port.
- Rinse – Rinse returns the normal flow of water through the filter but it maintains the exit flow routed to the waste port. After a backwash some particles may still be left in the pipes so to avoid that dirt being ushered to the pool, we need to rinse.
The Spider Gasket
If the valve is the highway interchange of your water then the spider gasket would be the guard rail. These gasket spokes act as dividers to ensure the path of the water stays true. If your multiport valve has a drip coming from the waste port line, most pool technicians will jump for the spider gasket.
The spider gasket is located either on the diverter pinwheel or the base of the valve the diverter faces. When we select a function on a multiport valve and release the handle, we drop the diverter onto the spider gasket. If the gasket has become worn and warped then the water will seep through the seam and end up in the waste.
The Fix: The solution is pretty simple, replace the gasket. Some gasket replacements are simple, remove the valve cover and old gasket, then lube in a new one. Other gaskets are glued into the diverter which requires a few extra steps. If you want a step by step guide on the different ways to replace a spider gasket read this: How to Replace a Spider Gasket on a Multiport Valve
The Diverter Spring
That tension we feel when spinning the selector handle is created by the diverter spring. Besides making it hard to spin the handle, the spring serves the purpose of locking
The Fix: Replace spring, which to be honest, is not fun at all. The spring is sandwiched on the diverter assembly which means it must be disassembled and assembled again. The hard part is getting the spring depressed enough to secure the handle pivot rod. If you are feeling brave and want to attempt a spring replacement, please follow our guide: How To Replace a Pool Multiport Valve Spring
The valve cover o-ring is found in the seam between the valve cover and main housing. If water is found leaking from this seam then this gasket would be your culprit. To access the gasket we would simply remove the 6 – 8 screws on the valve cover to remove it, peel out the o-ring, clean the groove, lube the new o-ring and re-attach screws.
The Fix: Read an inch above this line.
Valve to Filter Connection
Whether the valve is a top mount or a sidemount, it has to connect to the filter somehow. At that joint connection there is a gasket holding on for dear life. Because of the high flow at these connections, a blowout is somewhat common and easy to spot.
The Fix: Remove the valve from the filter and replace gaskets. Hopefully, the valve is piped in with unions so its removal is not a pain in the neck. Once the valve is off, find the gasket and apply a freshly lubed replacement.
Thanks for skimming through our pool musings. If you have any further questions about pools, valves or otherwise, feel free to give us a call at 877-372-6038.