The Complete Guide To Buying and Maintaining Unicel Filters For a Chlorine Pool or Spa

Unicel is one of the most respected names in the pool filter industry, touting a number of features and advantages not found in many of their competitors’ products. If you’re in the market for a new pool filter, have a read through this guide to what Unicel has to offer, including what features you need to look for and how to maintain the filter after you’ve installed and used it for a while.

Features and Choosing the Right Filter

Perhaps one of the most interesting features in the current line of Unicel pool filters (as of this writing) is the “wheel” device that sites in the middle of the filter element.  The purpose of this part is to add structural reinforcement into the middle of the filter, preventing the eventual collapse that many filters go through as they age.  This collapse generally happens when the filter is not properly cleaned and maintained (see below for maintenance information), so you have far less to worry about if you go through this process on a regular basis.  There are other companies that distribute these reinforcements, and if you would like to use one of these products with a Unicel filter, you can simply remove the reinforcement and replace it with your chosen part.  The removal process basically boils down to jiggling the the wheel back and forth, slowly edging it out from the center of the element.

Since Unicel specializes in cartridge filters rather than entire pool systems, by necessity they offer customized solutions that will be compatible with specific pools.  First, you’ll need to choose the manufacturer of your pool in order to determine the basic format that the filter will come in.  Everything from the diameter and length of the filter, all the way down to what kind of connection is used between the cartridge and the rest of your existing system can be determined.

Regarding the end caps on the cartridge, you’ll need to choose both a top and bottom cap connection.  There are too many connection types to really mention here, but Unicel makes it quite easy to find what you are looking for just by matching the specifications in the literature that came with your existing filter system to what is being offered at Unicel.  They support anything from threaded connectors to molded cone connectors, so you should be able to find what you need.  Even if you have an issue with choosing the cap types, someone from the company will be able to help you make the decision, so don’t let any perceived complexity put you off the task of replacing your filter cartridge.

Once you choose the correct connection types as well as length and diameter, Unicel will be able to tell you which of their filters is compatible with your system.  This narrows down the choices immensely, allowing the customer to focus in on what truly applies to their unique setup.

Maintenance

If you’re simply trying to clean a Unicel filter, first take note of whether you’re using chlorine or a substance called “Baquacil.”  Baquacil is a chlorine alternative that is advertised to be less irritating to the eyes and skin while performing the task of fighting off harmful bacteria as well as naturally occurring substances like algae.  The cleaning method you choose will be dependent on which of these solutions you use.  In this article, I am going to focus on dealing with chlorine pools only.

If you are cleaning a filter used in a chlorine swimming pool, then first you need to know the initial water pressure that occurs in the filter canister when using a new filter.  If the current water pressure is 8 PSI or more above the pressure with a new filter, then it’s time to clean! This makes sense if you think about it:  More water pressure means less water is getting through the system, which in turn means there are blockages on the filter.  Once the 8 PSI above normal mark is reached, the blockage is significant enough to be addressed with a good cleaning.

If you’re trying to clean Unicel spa filters, then you ideally should have a consistent cleaning schedule that is based on how often the spa is in use.  Obviously, a spa that is used only occasionally is going to need far less maintenance than one that is heavily trafficked throughout the day.

Once you have compared the PSI readings and determined that the filter needs to be cleaned, go through the following steps (quoted from Unicel’s site):

1. Remove the cartridge from the filter housing following the manufacture’s instructions.
2. Use a garden hose with a straight flow nozzle to wash down the filter element. Work from the top down, holding the nozzle at a 45 degree angle, and wash all the pleats with emphasis between pleats.
3. Rinse until all dirt and debris is gone.
4. For all spa cartridges and elements used in swimming pools where perspiration, suntan lotions, and other oils are present, soak the element for at least one hour (over night is more effective) in (1) a commercial filter cleaner; or (2) one cup trisodium phosphate (TSP) to five gallons water; or (3) one cup dishwasher detergent to five gallons of water.
5. Rinse the cartridge again to remove oils and cleaning solution.
6. If the filter has a coating of algae, calcium carbonate (residue from calcium hypochlorite), iron, or other minerals, soak the cartridge in a solution of one part muriatic acid to twenty parts water until all bubbling stops. WARNING: Failure to remove all oils and cleaning solution before acid soaking will result in a permanent restriction of water flow and cause premature cartridge failure.
7. Rinse the cartridge clean an reassemble housing.

Bonus:  Check Out This Helpful Video on Backwashing a Pool Filter

Thanks to 1800Pools.com for doing an excellent job on the video and sharing it on Youtube!