Envision Peripherals Series Leak Testing, System Evacuation, Initial System Charge Calculation

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NS SPLIT INSTALLATION MANUAL

Refrigeration (continued)

Leak Testing

The refrigeration line set must be pressurized and checked for leaks before purging and charging the unit. To pressurize the line set, attach refrigerant gauges to the service ports and add an inert gas (nitrogen or dry carbon dioxide) until pres- sure reaches 60 to 90 PSIG. Never use oxygen or acetylene to pressure test. Use an electronic leak detector or a good quality bubble solution to detect leaks on all connections made in the field. Check the service valve ports and stem for leaks and all connections made in the field. If a leak is found, repair it and repeat the above steps. For safety reasons do not pres- surize the system above 150 psi. Purge pressure from line set. The system is now ready for evacuating and charging.

System Evacuation

Ensure that the line set and air coil are evacuated before opening service valves to the split unit. The line set must be evacuated to at least 200 microns to remove the moisture and air that may still be in the line set and coil. Evacuate the sys- tem through both service ports to prevent false readings on the gauge because of pressure drop through service ports.

Initial System Charge Calculation

The Envision unit comes with a factory pre-charge. This volume is not sufficient to run the system. Additional refrigerant must be added for the lineset. This additional charge added to the factory pre-charge of the Envision unit should be esti- mated using the following equation:

Addition to Factory Charge = (lineset length x oz. per ft) + (20 oz. for accumulator)

The lineset charge should be calculated by multiplying the length times 0.5 oz./ft for 3/8” liquid line and 1.0 oz/ft for 1/2” liquid line in R-410A systems. The suction line will not hold ‘liquid’ and can be ignored for the calculation. This should result in a slightly under-charged unit exhibiting low subcooling and high superheat. As charge is added, the subcooling should rise and the superheat should fall until 8-16 degrees of superheat is reached when the TXV should be metering the system. See operating details in the startup section of this manual for exact superheat and subcooling values.

Example: 038 with 40 foot of 3/8” liquid line.

Additional to be added = (40 ft x 0.5 oz./ft) + (20 oz. for accumulator) = 40 oz.

Solution: 40 oz. should be added to the existing 56 oz. of factory charge as an initial charge.

Charging the System

Charge Method – After purging and evacuating the line set, fully open the service valves counterclockwise. Add R-410A (liquid) into the liquid line service port until the pressure in the system reaches approximately 200 PSIG. Never add liquid refrigerant into the suction side of a compressor. Start the unit and measure superheat and subcooling. Keep adding refrig- erant until the unit meets the superheat and subcooling values on page 24.

Checking Superheat and Subcooling

Determining Superheat

1.Measure the temperature of the suction line at the point where the expansion valve bulb is clamped.

2.Determine the suction pressure in the suction line by attaching refrigeration gauges to the schrader connection on the suction side of the compressor.

3.Convert the pressure obtained in Step 2 to the saturation temperature by using the R-410A Pressure/Temperature Con- version Chart on page 23.

4.Subtract the temperature obtained in Step 3 from Step 1. The difference is the amount of superheat for the unit. Refer to tables on page 24 for superheat ranges at specific entering water conditions.

Superheat Adjustment

TXV’s are factory set to a specific superheat; however, the superheat should be adjusted for the application. To adjust the TXV to other superheat settings:

1.Remove the seal cap from the bottom of the valve.

2.Turn the adjustment screw clockwise to increase superheat and counterclockwise to decrease superheat. One complete 360° turn changes the superheat approximately 3-4°F, regardless of refrigerant type. You may need to allow as much as 30 minutes after the adjustment is made for the system to stabilize.

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Contents 410A Refrigerant 4, 5, 6 Ton Dual Capacity Geothermal/Water Source Outdoor Split Heat PumpsPage Table of Contents Model Nomenclature Physical CharacteristicsGeneral Installation Information Utilizing Existing Coil or Air Handler Equipment SelectionConnection to Air Coil Air Handler InstallationDual Fuel Systems Electrical Data Thermostat WiringElectrical GeneralWater Piping Closed Loop Earth coupled Systems Outdoor InstallationsConnecting To Earth Loop Flow Center InstallationLine Set Sizes Air Handler NomenclatureAir Handler Coil Data `6O\RZS`RSZcPS`@ST`WUS`O\b  $ ! !$ $ Refrigerant Coil Compatibility Maximum One-Way Line Length Heat Recovery Unit for Domestic Hot WaterWater Tank Preparation Heat Recovery ConnectionsHeat Recovery Startup Plumbing Installation24V Accessory relay see SW2 3 for description of operation Wiring SchematicsMicroprocessor Control Lockout Conditions Fan G onlySTG1 STG2 STG3 Emerg Dual Capacity Units Operation Logic DataFreeze Sensing Setting DIP Switch SettingsCaused by excessive heat RefrigerationCharging the System Leak TestingSystem Evacuation Initial System Charge CalculationDetermining Subcooling Pressure/Temperature Coversion Chart for R-410A Dual Capacity Models Unit Operating ParametersDual Capacity Pressure Drop and Recommended Flow RatesStartup Steps Before Powering Unit, Check The FollowingUnit Startup Final Evaluation Heating Cycle Analysis Unit Startup/TroubleshootingRefrigerant Systems TroubleshootingLED Definitions and Diagnostics Standard Microprocessor ControlsReplacement Procedures Preventive MaintenanceNS026 thru NS072 Physical DimensionsCabinet Dimensions and Refrigerant Piping Connections Installation Notes Page Envision Series NS Outdoor Split

Series specifications

Envision Peripherals, a leading provider of display solutions, offers a wide range of products under its Series lineup tailored to meet diverse consumer needs in the realms of home, office, and gaming. With a focus on quality, performance, and user experience, the Envision Peripherals Series stands out in the crowded display market.

One of the main features of the Envision Peripherals Series is its commitment to high-definition displays. The Series includes a variety of monitors that offer resolutions starting from Full HD (1920x1080) up to 4K Ultra HD (3840x2160). This ensures that users can enjoy crisp and clear visuals whether they are working, watching movies, or gaming. The use of IPS (In-Plane Switching) technology in many of the monitors provides wide viewing angles and accurate color reproduction, making it perfect for creative professionals and content consumers alike.

In terms of technological advancements, the Envision Peripherals Series incorporates adaptive sync technology, such as AMD FreeSync and NVIDIA G-Sync compatibility. This feature reduces screen tearing and stuttering, providing a smoother gaming experience for competitive gamers. Additionally, many models in this series come equipped with high refresh rates, often reaching up to 144Hz, which is essential for fast-paced gaming applications.

The design of Envision Peripherals monitors is nothing to overlook either. Slim bezels and a modern aesthetic are standard across the Series, allowing for a sleek and professional look that fits well in any setting. Furthermore, some models offer ergonomic adjustments such as height, tilt, and swivel options, ensuring comfort during extended use.

Connectivity is another strong suit of the Envision Peripherals Series. Most monitors come with multiple input options, including HDMI, DisplayPort, and even USB-C in select models. This versatility allows easy connection to a variety of devices, from computers to gaming consoles.

Lastly, the emphasis on eye care technology, such as blue light filters and flicker-free screens, highlights Envision Peripherals' commitment to user health and comfort over prolonged periods of use. Overall, the Envision Peripherals Series combines exceptional visual quality, advanced gaming technologies, ergonomic design, and user-friendly connectivity, making it a top choice for consumers seeking a reliable and versatile display solution.
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