Safe Chemical Solutions Since 1942






Rydlyme Container Sizes


RYDLYME is available in various sizes:
Tanker or other bulk sizes available upon request.
  • 1-gallon
  • 4-gallon Case (1 gal. container x 4)
  • 5-gallon Jug
  • 30-gallon Drum
  • 55-gallon Drum
  • 330-gallon Tote

Calcium and Limescale Descaler

For more than 75 years, RYDLYME biodegradable descaler has been used to safely and efficiently dissolve tough mineral deposits, such as water scale, lime scale, calcium, rust and even struvite. This revolutionary descaler is fortified with a complex formula of wetting and penetrating agents that dissolve mineral deposits into solution for quick and easy disposal.

Key steps:

  1. Perform regular maintenance. Have a scheduled RYDLYME descaler maintenance program will help equipment function properly and you will save money!
  2. Record before and after temperature. This will help calculate the operating savings!
  3. Know how much. Call Apex Engineering Products at 630-820-8888 to discuss the quantity needed before performing the procedure! You may be surprised at how much calcium, limescale & rust RYDLYME can descale…

Scale Removal Methods:

Read the following procedures below to find out more information on removing scale from various applications!

Basic Boiler Descaling

  1. Shut down boiler.
  2. Blow down with pressure still on.
  3. Close steam valve.
  4. Drain and flush unit.
  5. Add RYDLYME, and then top off with water.
  6. Circulate from drain piping and back into top of boiler through the opening where the pressure relief valve was removed. Top of boiler or circulating drum should be vented to atmosphere to allow gases to escape.
  7. Circulate at least 4 hours. Longer for larger boilers, but no more than 8 hours.
  8. Open steam valve.
  9. Drain, flush, re-fill and start up.

Basic Heat Exchanger Descaling

  1. Isolate and drain the water-side of the exchanger to be cleaned.
  2. Place a 1” ball valve between the isolation valves and the heat exchanger on both the supply and return.
  3. Attach the RYDLYME pump and hoses so the RYDLYME will be pumped in the bottom or supply, and back out the top or return. 
  4. Begin pumping all the required RYDLYME into the exchanger. Once that is accomplished, begin to add water to complete the circulation. Please note: The calcium deposit will take up volume within the heat exchanger, so you will not be able to add the same amount of water in the beginning.
  5. Continue circulating the solution for the recommended amount of time. As the circulation progresses and the product dissolves the deposits inside the unit, the volume will increase. To account for the increase in volume, please add water to the circulation vessel, as needed. If you begin adding a lot of water, please be aware, it is possible there is a leak in the system.
  6. It is a good idea to periodically check the effectiveness of the solution while circulation is in progress. This can be accomplished by utilizing a pH meter and as long as the solution retains a low pH, the product is active. Should the circulating solution reach a pH of 5.5 to 7.0 before the recommended time is up, you will need to add more RYDLYME and possibly extend the circulation time.
  7. Upon completion of the recommended circulation time, the solution may be purged to a normal sewer and flushed with water. This process is completed by placing the return hose in the drain and adding water to the circulation container until the discharge line runs clear.
  8. The unit is ready to be returned to service.
  9. The same instructions may be used for plate and frame type heat exchangers. For volumes, please follow noted formula.

Basic Mixer Descaling

  1. Take mixer out of service.
  2. Close water supply valve at header.
  3. Drain all water from all sections of mixer.
  4. Connect RYDLYME pump discharge hose to water header. Header usually supplies all circuits.
  5. Connect return hoses to drain lines from all circuits and place into RYDLYME receiver.
  6. Close water supply valves to gate and jacket circuits.
  7. Start pump and pump RYDLYME into rotors to purge the water from this circuit to sewer. When RYDLYME begins to discharge from this hose, return to the receiver.
  8. Open water supply valve to gate and maintain RYDLYME circulation through this circuit.
  9. Open water supply valve to jacket and maintain RYDLYME circulation through this circuit.
  10. If any one circuit is NOT flowing properly, restrict RYDLYME flow in other circuits until flow returns to normal in this circuit.
  11. Circulate RYDLYME through all circuits of mixer until clean.
  12. It is suggested to periodically rotate the rotors during RYDLYME cleaning to assure that RYDLYME is in contact with all of the lobes of the rotor.
  13. Upon completion of cleaning, flush all RYDLYME from all circuits with fresh water.
  14. Disconnect pump and all hoses. The mixer is now ready to be returned to service.

Basic Vacuum Pump Descaling

  1. Write down current or “before” amperage readings, cfm at vacuum capacity and the vacuum in inches of mercury.
  2. Take unit out of service.
  3. Insert “blank” in flanges of discharge piping and tighten flange bolts.
  4. Remove bottom drain plug and allow all water to drain from pump casing. Replace bottom plug.
  5. Break seal water piping and attach RYDLYME pump discharge hose.
  6. Remove top plug, attach return hose and place other end of return hose in RYDLYME receiver.
  7. Add the prescribed quantity of RYDLYME to the receiver (see chart on back page) and start pump.
  8. In some instances additional water may be required to maintain circulation. Add only enough water to maintain circulation.
  9. Tighten pump seal packing to minimize leakage of RYDLYME.
  10. After 15 minutes of RYDLYME circulation, turn pump rotor 90 degrees by pulling on the drive belts or jacking the starter switch.
  11. Every 15 minutes thereafter, turn the pump rotor 90 degrees to assure a thorough cleaning of all interior parts of your pump, including hub, cones and rotor.
  12. Continue the circulation of RYDLYME for the recommended time frame.
  13. After the recommended circulation time, with intermittent turning of rotor, the pump should be clean and the rotor should turn freely.
  14. Shut off your pump and add a water supply hose into the receiving bucket. Disconnect your return hose from the pump system and put it in a drain. Turn on the water supply and the circulation pump, begin flushing out the unit for 20 to 30 minutes or until the discharge runs clear.
  15. Shut off circulation pump and disconnect all the RYDLYME hoses.
  16. Reconnect the seal water piping.
  17. Remove “blank” in flanges of the discharge piping and tighten flange bolts.
  18. Return pump or compressor to service.
  19. Adjust the seal water rate to manufacturer‘s recommendations.
  20. After unit has stabilized, write down current or “after” amperage readings, cfm at vacuum capacity and vacuum in inches of mercury.
  21. Compare “before” readings with the “after” readings. The difference between the “before” and “after” amperage readings multiplied by the cost per kw/hr at your facility, will help you determine the short payback time required to justify future RYDLYME cleanings. RYDLYME cleanings of your liquid ring vacuum pumps should be performed on a preventative or predictive maintenance schedule.

Basic Chiller & Cooling Tower Descaling

  1. Close make up water valve to tower basin.
  2. Turn off all chemical or non-chemical water treatment, conductivity meters and pH meters.
  3. It is recommended that all loose water scale, lime, mud, rust and other foreign matter be manually removed from tower basin prior to starting the cleaning.
  4. Lower the water level in the tower basin to a point where the pump can maintain circulation without cavitation and close the bleed-off valve.
  5. It is recommended that the fans be turned off during the cleaning
  6. Determine the proper amount of RYDLYME to be added to the system.
  7. To minimize excessive foaming, you may now slowly add required amount of RYDLYME to the cooling tower basin.
  8. The bubbling and foaming you will observe is a natural reaction of the RYDLYME dissolving the water-formed mineral deposits within the system.
  9. Once the RYDLYME is in the tower system, allow it to circulate. Start charting your pH readings or performing calcium spot tests to measure the effectiveness of the RYDLYME descaler solution during the cleaning. (“Testing the Effectiveness” is available on our website). If the RYDLYME descaler expends prior to the completion of the recommended circulation time, there is more scale in the system. It is recommended that you repeat steps 6-9 to complete the cleaning.
  10. It is recommended that the RYDLYME descaler solution be cycled out of the system to prepare for normal operation. At this time, strainers should also be removed, inspected and cleaned as well.
  11. Once the cleaning material has been cycled from the tower system, turn your conductivity, pH meters or any other equipment back on. Return the make-up water and bleed-off valves per the manufacturer’s recommendations. Lastly, resume normal system operation.

Basic Tankless Hot Water Heater Descaling

  1. Turn off gas and turn all valves to proper positions.
  2. Pour RYDLYME descaler and water into 5-gallon bucket.
  3. Connect hoses to appropriate hot and cold service valves.
  4. Place pump inside bucket, turn on pump and circulate.
  5. Flush unit, disconnect hoses and return unit to service.
  6. Dispose solution down normal drain or sewer.

RYDLYME Descaler Removes Calcium & Limescale

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Apex Engineering Products Corporation  |  1241 Shoreline Drive  |  Aurora, IL 60504  |  Tel: 800.451-6291 or 1.630.820.8888  |  Fax: 630.820.8886  |  Made in the U.S.A.

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