The many pool filter settings on a multiport valve on a swimming pool sand filter can be pretty confusing when you first get a pool. But, like most things, it is pretty simple once you know. You will soon understand what all of the pool filter valve positions mean.
There are normally 6 different pool filter settings on a multiport valve which are Filter, Backwash, Waste, Rinse, Recirculate and Closed. Some valves also have an additional 7th position which is Winterize.
Before I go into what each of the different pool filter settings does in detail I want to give one important word of warning. NEVER operate the selector lever on the multiport valve with the pool pump running. This can cause severe damage to the valve so always turn the pool pump off first.
Pool filter valve positions
I will go through what all the pool filter valve positions mean in turn and explain what each does.
This is the most often used of the various pool filter settings. It is the pool filter valve positions setting that your filter will spend most of its life on. Mostly it will be used when the pool pump runs on your timer to keep the water in the pool clean.
The filter setting is also the one you will use the most when vacuuming your pool. Whenever the dirt levels are not too high you can let the filter remove it and then backwash to eject it from the system. My article “How to clean dirt from the bottom of a pool” explains this process fully in a step by step guide.
When it is on the filter setting, and the pump is running, the water will be drawn into the system through the skimmers and bottom inlet (if you have one). It will then pass through the debris filter basket on the inlet side of the pump so that any large pieces of dirt, such as leaves, will be removed prior to passing through the pump as they could cause damage. The water then travels through the pump and into the top of the sand filter.
Here the magic happens. The water passes through the sand which traps any small particles of dust and other dirt. When it reaches the bottom of the filter it returns to the pool as clean water through the inlet jets, waterfall or whatever other similar feature you may have.
This will be one of the multiport valve positions you will use the second most frequently, after the filter setting.
You use this setting to clean the sand in the filter, often immediately after you vacuum the pool.
It works by the water being redirected the reverse way through the sand filter. So after leaving the pump it goes into the bottom of the filter and travels up through the sand, dislodging the dirt and debris as it goes. The water containing the debris then goes to the waste pipe and out of the system.
For a full guide to backwashing my article “How to backwash a pool – step by step” will explain everything.
You use the pool filter waste setting in the following three situations:
- When you wish to reduce the amount of water in the pool, perhaps after heavy rain or even to empty the pool fully.
- When your pool is very dirty you would vacuum to waste in the waste setting so the dirt goes straight out of the system and doesn’t clog up the filter.
- If you have a heavy infestation of algae then often the tiny particles won’t get trapped in the filter so will go straight back into the pool. Vacuuming on waste means they will be ejected out of the waste pipe and will not reenter the pool.
On the waste setting the water will be drawn into the system then passes through the debris filter basket on the inlet side of the pump. From there it is expelled from the system without passing through the filter via the waste pipe.
Depending on your system the water will either be sent straight into the sewer system or out into your yard/garden, often through a roll out waste hose so you can direct the water to an area of the garden you want.
You will only use this setting after you have backwashed the sand filter.
On the rinse setting the water travels the normal way through the sand and can remove a few remaining particles of dirt but its main function is to settle the sand back down ready for the filter to work. You normally run the pool pump for between 30 seconds and one minute on the rinse setting.
The water goes to waste when on the rinse setting and not back into the swimming pool.
Of all the pool filter valve positions, the recirculate pool pump setting is probably the one you will use the least. Actually what does recirculate mean on my pool pump is one of the most frequently asked questions I see on the various pool forums from new pool owners.
I don’t think I have ever used the recirculate setting actually. When to use recirculate on pool filter is perhaps after you have shocked the pool and want to mix the shock around the pool without it being absorbed by the filter.
Basically in this setting the water is drawn in through the skimmers as normal and, after passing through the pump, goes straight back into the pool via the inlet jets, waterfall etc without passing through the filter.
The closed setting can be used for the following two reasons:
- If your pool will not be used for some time, perhaps if it is empty or during the winter.
- When you want to empty the strainer basket that traps leaves etc before the water enters the pump. You close the valves from the skimmers and other inlets and then set the valve to closed. You can then remove the see-through lid from the basket housing and empty it without air running back through the system which could give an airlock, something you want to avoid. Once you have emptied the strainer basket and you have replaced it and screwed on the lid then the valves can be opened.
Not every multiport valve has this setting, although it will normally exist where the pool is located outside in a cold climate. It is generally found between the closed and the waste setting.
Generally it does not allow the handle to fully go down in this setting. It is designed to allow the water to expand a bit without damaging the valve should the water freeze.
Other types of filters and valves
DE (Diatomaceous Earth) filters
These generally have a multiport valve the same as you find on a sand filter system. So everything written above also applies to a DE filter system. DE filters are not backwashed as a frequently as sand filters however.
Cartridge filters do not use multiport valves as they do not require backwashing or rinsing. To clean the filter it is removed and cleaned manually or replaced with a new one).
On some sand and DE filter systems a series of slide valves are fitted instead of a single multiport valve. Opening and closing the valves in a particular combination gives the required settings for backwashing, filtering etc.
Pool filter settings Youtube video
You may wish to watch my video on What do the pool filter valve positions mean below. You can subscribe to my Youtube channel here.
Why is my pool filter leaking from the top?
This is likely to be because the O ring which seals the filter, preventing water leaking out and air from getting in. If this is the case then it will need to be replaced which is a fairly straightforward operation that most pool owners can carry out themselves.
What is the life expectancy of a pool sand filter?
The actual filter itself can last a long time provided it is maintained properly. The sand in the sand filter generally needs to be replaced every 5-7 years, depending on use.