If you have ever tried to vacuum your pool and realized after a short while that you had very little suction, you know the frustrations are real. So you walk around the pool and over to the filter system and take a peak. You find the pressure gauge is up, indicating that the filter is dirty. Didn’t I JUST clean this filter!? If you have a cartridge or DE filter, you take out the cartridge or grid and rinse it off well. If you have a sand filter, you flip it to backwash and then to rinse. Now, we should be already to go, right!?
But when you get back over to start vacuuming the pool again, there is STILL no pressure! What in the world is going on!? Let’s dive into what may be going on:
There may be something obstructing the flow of water through the motor and into the filter system, causing low suction. Here are a few locations to check for debris:
*Skimmer Basket – make sure you take it completely out, empty it, and make sure it is properly placed back in the correct direction.
*Between pump pot and motor – you’ll need to unscrew the pump pot from the motor in order to look and see if there is anything blocking the way between the pump pot and the motor itself. Once you unthread the pump pot off, you can reach your hand inside the hole and feel around for any debris. If the basket has been incorrectly positioned in the pump pot, debris can get lodged in this location.
Filter System media over-capacitated
Sand Filters: If you have tried backwashing and then rinsing and you still have low pressure, it could mean that there is a large buildup of algae and or debris inside the filter system that has compounded over the years and is not coming out when you backwash. The next thing we would recommend doing would be to use a Sand Filter Cleaner. This product is placed in the pump pot of the motor and once you secure the lid on the pump pot, you’ll kick the pump on for just a few seconds to get the product from the pump pot down into the sand filter, where it will sit in the filter system overnight to absorb through the sand. It Is important to leave your filter system turned off overnight to allow the product to work properly. In the morning, you will need to do a backwash and rinse of the filter system. If this does not fully solve the issue, the sand may need to be replaced to allow for proper circulation and filtration.
Cartridge/DE Filters: If you have a cartridge or DE filter, you can soak your cartridge in a large bucket or clean trashcan with a special solution that will help to degrease it much better than just rinsing it off with the garden hose. It is recommended to allow it to soak at least overnight (or a minimum of 8-12 hrs) before rinsing it off very well and then placing it back in the filter system. Cartridges need to be replaced anywhere from once a week on smaller filter systems to once a season. If you try cleaning the cartridge with no avail, it is recommended to replace the filter cartridge. DE grids typically do not go bad and don’t have to be replaced unless there is a puncture.
Air coming In
Low suction can also be caused by even a small amount of air being introduced into the circulation of the water, cutting down on the amount of suction the filter system will provide. This could be caused from a bad oring on your pump pot lid, a small pinhole in your vac hose or even in the hoses that flow the water to and from the pool. The hoses might not be tight as well and may be letting in just enough air and lowering the amount of suction you should normally have.
If you have tried all of these things and are still having issues, it would be best to have a technician look at the situation and discover what the problem may be. Please give us a call if you need any further assistance!