Maintenance

!Charging the System (by Certified HVAC technician) After all the piping is complete:

•Open both of the service valves on the condensing unit. The unit is pressurized with Nitrogen and you should hear the gas escaping through the service ports.

•With electrical power connected to the evaporator unit energize the solenoid valve (pressurize with dry Nitrogen) to 100psi. Leak test all fittings. Must hold 100psi for 30 minutes.

•If no leaks are found, leave solenoid valve energized and evacuate the system through both the liquid and suction service ports. Using a high vacuum pump, evacuate to 200 microns, measuring the vacuum with a digital micron gauge. When evacuation is complete, break vacuum and pressurize with liquid R-134A. refrigerant.

•With the electrical power turned on to the condensing unit, and the evaporator unit running, slowly feed liquid refrigerant (R134A) into the suction service port. As the suction pressure rises to 15 PSIG, the condensing unit will start. Slowly feed refrigerant while maintaining a pressure above 10 PSIG to prevent the compressor from short cycling. Slowly feed refrigerant with the compressor running until the sight glass is clear of all bubbles. Do not exceed 3.5 lbs of refrigerant. Check superheat at evaporator outlet. Superheat should be at 10°-12°. Check the compressor crankcase temperature after 30 minute run time – should be hot 115°to 140°. If cool, superheat is too low. Adjust TXV to recommended superheat.

•Allow the system to operate for one hour and then check the refrigerant level in the sight glass again. Additional refrigerant may be required as the temperature of the enclosure is lowered to approximately 55F or the ambient temperature at the condensing unit rises above the temperature at which the unit was initially charged. Depending on temperature, the “high side” should be approximately 175 lbs. The ”low side” 28 lbs or more to keep the evaporator from icing. It is recommended while charging to use a digital refrigerant scale for better accuracy in measuring the amount of charge.

The WhisperKOOL system is designed to operate with very little maintenance required. Do check the condensing unit and evaporator coils, and vacuum them every three months.

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