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When should you change the VIP cooling system water?
Monitor the conductivity of the water. If the conductivity should exceed 10 µmhos/cm (or µsiemens), replace the deionizer cartridge. If the conductivity should ever exceed 100 µmhos/cm, flush the system with deionized water until the conductivity has returned to the recommended levels. Add industrial-grade inhibitors and additives-free glycol as needed for freeze protection. Also, due to differences in ethylene and propylene glycol, it is important to use the one for which your system was designed.
How would I know the level of freeze protection for my existing cooling fluid?
Take a small sample of the cooling fluid and use a standard automotive anti-freeze tester to measure the freeze protection level.
The glycol concentration is continually dropping in my cooling system. What should I do?
There are numerous reasons why this may be occurring. One possibility is that there is a leak in the system. Find and repair any leaks. If there are no leaks, the cause may be that fluid is added while the system is off. Adding glycol to the system while the pumps are off will result in high concentrations of glycol at the fill point while none is distributed to the rest of the system. Run the pumps to circulate the fluid before testing the concentration. Also, always be sure that the tower diversion valve is open when glycol is added so that the mixture can flow through the tower. If this is not done, the tower may remain full of 100% water while the rest has the correct concentration of glycol.
Why can’t I add more glycol to my water system?
The system is most likely already full. The fill valve will automatically close when the pre-charge pressure is reached. At this point it will not allow more fluid to be added to the system. Some fluid will need to be removed before more can be added. The excess fluid can be collected in a mixing tank where glycol is added, then pumped back into the system.
Why is the pump discharge pressure lower than specified on the piping diagram?
The throttle valve may not be set correctly. With the pump running, adjust the throttle valve (first valve after pump discharge) until proper pressure is reached.
I’m noticing large variations in pressure that occur with changes in water temperature. Is this normal?
There may be air trapped in the system. If so, use air bleed valves to purge air from the system. This is more effective if the system is turned off for a while to allow small air bubbles to accumulate in the system high points. Extreme cases may require the use of an air separator. If this does not help, additional expansion capacity may be required and additional expansion tanks can be added to the system.
Why is there high pump discharge pressure regardless of throttle valve setting?
It is possible that there is a closed isolation valve somewhere in the system. Check to make sure that all main piping valves are completely open and that any by-pass or throttling valves are properly adjusted. If this does not work, you can also check to see if there is a clogged strainer or other obstruction in the piping. Flush the strainer or remove and clean. You may also want to refer to the piping diagram and ensure that the piping is not too small or that the piping runs are too long. The motor nameplate for wiring requirements should also be checked to be sure that the motor voltage and frequency is correct.