How Did My UV Treatment System Fail a Water Test?
Written by Rebekah Hildebrand
May 5, 2020
In most cases, a UV treatment system will effectively sanitize water to pass a water test. Results should improve immediately when all installation steps are followed properly. It is important to remember that an ultraviolet treatment system works by disinfecting water that comes into contact with UV rays. As a result, micro-organisms beyond the treatment point may continue to live and can lead to another failed water test.
There are a few troubleshooting options in the case of a failed water test when a UV system is in use:
"E. coli Bacteria", by NIAID, licensed under CC BY 2.0
Shocking the Plumbing
It is recommended that the lines be shocked when the unit is initially installed so that the pre-existing bacteria can be eliminated. Similarly, if a system has been disconnected or off during any period of time, bacteria may begin to grow in the pipes again. Directions for shocking the plumbing lines can be found in an article here.
If your downline has been shocked and operation of your UV system has been continuous, the unit may have a bulb issue. A UV bulb is rated effective for 9,000 hours or one year of operation. After one year, the bulb may still be lit, but it will begin to lose the ability to sterilize all types of micro-organisms. It is important to replace your UV bulb annually to maintain successful operation.
Dirty Quartz Sleeve
Since the bulb treats water as it passes, a dirty quartz sleeve could cause the UV rays to miss micro-organisms that pass. Directions to check and clean a quartz sleeve can be found in an article here.
While it is extremely rare for a bulb to fail, the ballast is more likely to experience issues. Replacing the ballast is an easy task that does not require any experience; however, it may be necessary to sanitize the plumbing lines after not operating for a period of time. Directions for replacing the ballast can be found here.
If your system is still failing a water test, please call our customer service team (410-827-8885) or a certified plumber for assistance.