I contacted Sawyer regarding the reduced flow rate of my water filter and wondering if I need a replacement cartridge (which is no longer available). Below is their response. I thought I share it with you because I thought it was helpful.
It sounds as though your filter is just blocked, either from particulates or minerals. With proper cleaning and if stored in a cool dry place out of direct UV light, your filter should last a lifetime. More often than not, the filters that are mailed to us are restored by our engineers using the process below...
A blocked filter can almost always be recovered by soaking the filter in hot water (not to exceed 135 F) for an hour or so, and then backflushing several times with hot water as hard as possible. The trick to a successful backwashing is to be very forceful with the process.
Water will always take the path of least resistance, so in order to fully flush out the filter and restore its flow rate, make sure you are exerting as much pressure as you can, especially during the first couple of passes. If that doesn't work and your flow rate is still slow, your water source might be mineral rich, so we would suggest soaking it in vinegar for half an hour or so, and then repeating the process with hot water backflushes.
To sanitize the filter, we'd recommend using a weak bleach solution (one capful of bleach per Liter of water). Slosh the weak bleach solution around in your pouch and run it through the filter. After the pouch and filter have been sanitized, let the filter sit upright with sufficient ventilation to dry out before storing the filter in a cool/dry location away from direct sun exposure. Some tips:
Trying to filter water through a blocked filter will always make things worse.
Backflush, backflush, backflush,……
A second or third soak may be necessary. The more you do this, the more recovery you will achieve.
If after trying this your filter is still blocked, we would be happy to have one of our engineers take a look at your filter. Note: please check with us to see if we are receiving them in the months from October through May, due to possible freezing conditions in various parts of the country.
Please safely pack and send it in a properly sized box with sufficient packing material to avoid physical damage in transit. Envelopes and utility mailers will be returned. Include either a note stating the issue or a printed copy of this email chain.
Packages can be sent to the address below.
Sawyer Products
Filter Review
605 7th Ave North
Safety Harbor, FL 34695
Hope that helps!
