Regular backwashing of your pool filter is essential to maintain crystal-clear water and extend the life of your swimming pool system. Whether you’re using a sand filter, DE (diatomaceous earth) filter, or a multiport valve system, this guide will show you how to backwash your pool filters like a pro.
If you’re in Cape Town and need help, our trusted swimming pool services team offers filter cleaning, installations, and full repairs throughout the Western Cape.
Why Backwashing Matters for Pool Maintenance
Backwashing helps to flush out dirt, oils, and debris that have been trapped by your pool filter. Without this, pressure builds up, water becomes cloudy, and your pool equipment works overtime — leading to costly repairs.
Regular backwashing = better circulation + cleaner water + longer equipment life.
Types of Pool Filters That Need Backwashing
- Sand Filters
- DE Filters
- Cartridge filters do not require backwashing; they need manual cleaning instead.
Step-by-Step: How to Backwash a Sand Filter
Sand pool filters are the most common in Cape Town. Here’s how to backwash them:
- Turn off the pool pump.
- Set the multiport valve to “Backwash.”
- Attach the backwash hose and run the pump for 2–3 minutes or until the sight glass shows clear water.
- Turn the valve to “Rinse” and run for 1 minute.
- Return the valve to “Filter.”
- Turn on the pump and check the pressure gauge.
Backwash when your pressure gauge is 8–10 PSI above normal.
Step-by-Step: How to Backwash a DE Pool Filter
Diatomaceous earth (DE) filters offer finer filtration but require a similar backwashing process:
- Turn off the pool pump.
- Open the air relief valve to release pressure.
- Turn the multiport valve to “Backwash.”
- Run the pump for 3–5 minutes or until water runs clear.
- Set the valve to “Rinse” for 1 minute.
- Return to “Filter” and restart the pump.
- Add fresh DE powder through the skimmer.
Don’t forget to re-add DE powder — your filter won’t work properly without it.
What About Cartridge Filters?
Cartridge filters do not require backwashing. Instead, remove the cartridge and manually clean it with a garden hose or soak in a filter cleaner.
Cost of Backwashing vs. Filter Replacement in Cape Town
| Service | Average Cost (ZAR) | Details |
|---|---|---|
| Basic Backwash (Sand/DE) | R400–R700 | Includes inspection & rinse cycle |
| Cartridge Filter Cleaning | R500–R950 | Manual cleaning & pressure testing |
| DE Powder Refill (After Backwash) | R150–R300 | Per refill |
| New Sand Filter Installation | R4,500–R7,000 | Labour + Equipment |
| New DE Filter System | R6,000–R10,000 | Premium performance + installation |
Routine backwashing is far more affordable than a full replacement. Stay on top of your filter maintenance!
Benefits of Hiring a Cape Town Pool Service Company
- Expert filter backwashing & inspections
- Pool filter repairs and replacements
- Pool pump installations & servicing
- Comprehensive maintenance packages
We serve Cape Town, Brackenfell, Durbanville, Stellenbosch, and surrounding Western Cape areas.
Frequently Asked Questions (FAQ)
How often should I backwash my pool filter?
Backwash every 1–2 weeks during heavy usage or when the pressure gauge rises 8–10 PSI above normal.
Can I backwash my pool filter myself?
Yes, but professional swimming pool filter services in Cape Town are recommended for optimal performance and safety checks.
What happens if I don’t backwash my filter?
Your pool water will become cloudy, the pump may overheat, and it can lead to costly repairs or replacements.
How do I know my pool filter needs replacement?
If you’ve backwashed regularly and still notice poor circulation, rising pressure, or water clarity issues, it may be time for a new system.
How long does a sand filter last?
With proper maintenance, sand filters last about 5–7 years in Cape Town conditions.
Internal Links
- How to Clean All Types of Pool Filters
- Signs Your Pool Needs Repairs in Cape Town
- Choosing the Right Pool Pump for Your System
