How to Backwash a Hayward Pool Filter

Proper pool maintenance keeps your swimming pool or spa clean, safe, and pleasant to use. One of the most important parts of pool maintenance is the regular cleaning or backwashing of your pool filter. Hayward is a leading manufacturer of high-quality pool filters. In this article, we’ll explain the different types of Hayward filters, how they work, and provide step-by-step instructions for cleaning and backwashing them.

What is a Hayward Pool Filter?

A Hayward pool filter removes dirt, debris, and impurities from pool water, keeping it clean and clear. As water flows through the filter, the filter media traps particles, removing them from the water. Over time, the trapped debris builds up, and the filter needs to be cleaned.

Types of Hayward Pool Filters

Hayward offers three main types of pool filters:

  • Hayward Cartridge Filters: Cartridge filters use pleated polyester cartridges to filter water. Water passes through the cartridge, which captures debris. Cartridge filters are easy to maintain but must be removed and cleaned periodically.
  • Diatomaceous Earth (DE) Filters: DE filters use diatomaceous earth, a fine powder made from fossilized organisms, to filter water. The DE powder coats the filter grids, trapping even microscopic particles as water passes through. DE filters provide superior water clarity but require more maintenance than cartridge filters. Maintenance includes regular backwashing, where the water flow is reversed to flush trapped debris out of the filter medium.
  • Sand Filters: Sand filters use a special-grade sand to filter water. As water flows through the sand, dirt, and debris are trapped. Sand filters are simple to operate and maintain. Like DE filters, they are cleaned by backwashing.

Hayward Pool Filter Parts

While the specifics vary by model, all Hayward filters have several key components:

  • Tank: The tank houses the filter media.
  • Pressure gauge: Measures the pressure inside the filter, indicating when cleaning is needed.
  • Multiport valve (sand and DE filters): Controls the water flow for filtering and backwashing.
  • Drain plug: For draining water from the tank for maintenance.

How to Clean a Hayward Pool Filter

Cartridge filters should be cleaned regularly. How often depends on the amount of debris in the pool and the filter's condition. A rule of thumb is to clean pool filters if the pressure is 8 to 10 PSI over the baseline pressure measured with a clean filter.

The process for cleaning a Hayward cartridge filter is as follows.

  1. Turn off the pump and close the valves to isolate the filter.
  2. Open the air relief valve on top of the filter and drain any water from the tank.
  3. Remove the clamps or collar holding the top of the tank in place, and remove the lid.
  4. Lift out the cartridges and rinse them thoroughly with a hose, spraying between the pleats. If they are very dirty, soak them in a filter-cleaning solution.
  5. Inspect the cartridges for wear. If they are damaged or more than three years old, replace them.
  6. Reinstall the clean cartridges, replace the lid, and restart the system.

How to Backwash a Hayward Pool Filter

Backwashing reverses the flow of water to push trapped dirt and debris out of the filter medium. Sand and DE filters are cleaned through backwashing.

  1. Turn off the pump. Set the multiport valve to the “Backwash” position.
  2. Turn the pump on for 2–3 minutes or until the water in the sight glass runs clear.
  3. Turn the pump off. Set the multiport valve to the “Rinse” position. Run the pump for 30 seconds.
  4. Turn the pump off. Set the multiport valve to “Filter” and turn the pump on.
  5. For DE filters, add fresh DE powder to recoat the grids.

How to Replace a Hayward Pool Filter

If your Hayward cartridge filter is damaged or has reached the end of its life (usually after three years), it’s time for a replacement.

Here’s how to replace your filter:

  1. Follow steps 1–3 from the cleaning procedure above to access the cartridges.
  2. Remove the old cartridges and discard them.
  3. Insert the new cartridges, making sure they are correctly seated.
  4. Replace the lid, secure the clamps or collar, and restart the system.

You can purchase high-quality replacements for Hayward filters from Atomic Filters, including replacements for the Hayward C-120 and C-120-RE and the Hayward C-200 and CX200-RE .

FAQs

How often should you backwash a Hayward pool filter?

It depends on usage, but in general, it’s time to backwash sand and DE filters when the pressure gauge reads 8–10 psi above the normal operating pressure. As a guideline, backwash DE filters every month or so and sand filters every 2 weeks, and more often if the pool appears dirty or the pressure rises.

How often should you replace a Hayward pool filter?

Cartridge filters typically last from 1 to 2 years but can last up to three years with regular maintenance and cleaning before needing replacement. Sand should be replaced every 5–7 years. DE grids can last 10+ years with proper care.

What should the pressure be on a Hayward pool filter?

Normal operating pressure is usually between 10 and 20 psi, but it varies by model. Consult your owner’s manual for specifics.

What types of pools use Hayward filters?

Hayward filters are versatile and can be used on inground concrete, fiberglass, vinyl liner pools, and above-ground pools. The right size and type of filter depends on your pool’s volume and filtration needs.

Use Full site for recurring orders