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Hi! I’m your Hydrominder. Do you remember me? The Hydrominder has become the industry standard for liquid level maintenance for over 20 years and proven successful for many applications. As your hydrominder, I’m the guy in your equipment room that controls chemical usage, strength, colours, fragrance levels, foaminess, performance and more! I can make or break you, especially if you ignore me. I work hard for you and do exactly what you tell me, a silent employee, but every once in a while, I need some attention.

Your Hydrominder is basically a solenoid operated by a weighted float. As the soap level drops in the chemical tank, the float has enough weight to pull a magnet down the plunger stem causing the diaphragm to open. As the tank fills the float rises, and a spring under the magnet returns it to the upper position closing the diaphragm. Thus the hydrominder is a great tool for automatically maintaining the level of ready-to-use soap solution. The water coming out of the valve then passes through an educator. The educator generates the venturi which draws the soap or concentrates out of the drum through a metering tip, either screw or push in type. The soap solution then flows down the discharge hose into the tank. In the discharge hose there is a flow restrictor which is important to the operation of the eductor, so it is important that this hose is in place. If this hose comes off, the educator/venturi will not operate correctly.

So here are some tips for maintaining your Hydrominder:

  • Remember that all chemicals are different viscosities (thicknesses) so you cannot rely on the tip colour and its corresponding ratio. Did you know this ratio only refers to the ratio using a water thin product? Concentrates are MUCH thicker than water and will not be used at an 80:1 ratio with a tip that says 80:1. To determine usage you will have to learn to flow test your chemicals.
  • A way to determine whether your Hydrominder is functioning at peak performance is to perform a test. Use a stop watch and run the line wide open for one Hydrominder for one minute then measure the volume change in the tank. Then, with a helper, do the same but open up the other 3 Hydrominders at the same time. If your volume change from the second test differs dramatically from the first test – with only one Hydrominder functioning – you could have a blocked inlet strainer or damaged diaphragm in the Hydrominder. A reduced water flow caused by this can result in weak dilutions in the tanks and poor results in your car wash bays.
  • Take an occasional look to make sure chemical dilution tips, water flow and float systems are intact and operational.
  • If you are experiencing problems with soap application in your car wash bays then the tanks are good place to start looking. Check all tank outlet strainers to make sure they are clean and not blocked.
  • Check the foot valve in the soap drum too, the soap should not drain back down the line to the soap drum. The foot valve may also become clogged preventing soap from being pulled up the suction line.
  • Your soap tank should also have a strainer on the outlet of the tank to prevent foreign objects potentially fouling the solenoids or check valves.
  • Change incoming chemical lines at least once a year.
  • Change the hose barb where tips are inserted at least once a year.
  • Inspect tips at least once a quarter and track what tips are used for each application.
  • Keep a spare Hydrominder, diaphragms, tips, strainers and a repair kit on hand, so you can easily replace or repair.
  • Know which size Hydrominder you use. Do you know that there are many different sizes of Hydrominders with different flow rates?
  • In the case of a Prowash/SuperSat installation the products that use a dual educator system will have an anti-siphon valve built in. A single educator system may need to have an anti siphon hole drilled in the discharge hose. This hole should be approximately 3 mm and located downstream of the flow restrictor, but above the full level of the soap tank. This will break the siphon and lessen the chance of solution leaking back into the soap drum and diluting it.
Contact our friendly staff at Prowash if you require any further assistance with your Hydrominder


© Prowash Australia
Author: Liz Reisman
Date Published: 11 November 2015