HI7004L is a ready-to-use pH 4.01 calibration buffer solution supplied in a 500 ml bottle. It is used to calibrate and verify pH electrodes and controllers in commercial pool water treatment, including Hanna Instruments dosing and measuring systems such as the BL120 series and HI3214 electrodes. Together with a pH 7.01 buffer it forms the standard two-point calibration set for pool pH probes.<\/p>\n
Suitable for any glass pH electrode or pH controller that requires standard NIST-style buffer calibration, including Hanna Instruments pool dosing panels, portable meters and inline pH probes. The buffer is brand-independent, so it can also be used with third-party pH electrodes installed in a pool circulation loop. It is a pH calibration solution only and is not suitable for ORP or conductivity probes.<\/p>\n
Rinse the electrode with clean water, shake off the excess and immerse the sensing bulb in a small quantity of buffer poured into a clean beaker. Follow the calibration routine of the meter or controller and wait for the reading to stabilise before confirming the point. Always pour out a fresh sample rather than dipping the probe into the bottle, and discard the used solution after each calibration.<\/p>\n
Keep the bottle tightly closed and store it away from direct sunlight and heat. An unopened bottle typically remains usable until the printed expiry date; once opened, the buffer should be replaced within a few months as absorbed carbon dioxide and contamination shift the value. Never return used solution to the bottle.<\/p>\n
Sold individually as a single 500 ml bottle of pH 4.01 buffer, not as a calibration kit. For a full two-point calibration order a pH 7.01 buffer separately, and add an electrode storage or cleaning solution if the probe is used continuously in pool water.<\/p>","protected":false},"excerpt":{"rendered":"