Line Set Cleaning for Retrofitting Procedure

Line Set Cleaning for Retrofitting Procedure

When installing a new R410A air-conditioning system to replace an existing R22 system, it may be possible to use the existing line set. Consult the OEM’s installation manual and determine if the line sizing is correct and proceed as follows:

1.Before starting any work put on approved safety goggles and nitrile gloves and remember to work only in a properly ventilated area.

2.Recover the existing R22 charge; it is illegal to vent any refrigerant.

3.Disconnect any electrical power feeds to the system including any solenoids or reversing valves.

4.Using a tubing cutter cut the liquid and suction line at both the condensing unit and

the evaporator.

5.Temporarily connect the liquid and suction lines at the evaporator using clear plastic tubing, suitable adapters and hose clamps.

6.Using an injection tool or a compression fitting and adapters, connect a refrigeration service hose to the suction line at the condensing unit location.

7.Position a clean container at the liquid line to catch solvent and contaminants as they are purged from the system. Purged material may include acids, oil and particulate debris which must be disposed of properly.

8.Connect the flush can valve as shown in Figure 1 and 2 or use a valve capable of connecting to 7/16” 28 thread. These valves are currently offered for sale at most refrigeration and air-conditioning wholesalers.

9.Connect the refrigeration service hose or refrigeration manifold set to the can valve and the suction line, invert the ST-20 can, open the valve and give a 15–20 second blast of ST-20 Flush. Inspect the clear tubing at the evaporator and look for liquid. If no liquid is present continue 15 second purges until it appears. Follow ST-20 with a regulated supply of dry nitrogen and push the solvent into the receiving container while observing the condition of the purged material. When the solvent runs clear with no oil or contaminants present the flushing operation is complete, follow with a dry nitrogen purge. Never pressurize the Genetron ST-20 container. Dispose of the waste material properly.

10.Connect the line set to the new evaporator and condensing unit and evacuate and leak check as per current guidelines.

Figure 1

Figure 2

ST-20 specifications

The Honeywell ST-20 is an advanced temperature and humidity data logger designed for monitoring environmental conditions in various settings, including laboratories, warehouses, and production facilities. Known for its reliability and accuracy, the ST-20 combines cutting-edge technology with user-friendly features, making it an essential tool for professionals in need of real-time data collection.

One of the standout features of the Honeywell ST-20 is its dual-channel capability, which allows it to monitor both temperature and humidity simultaneously. This dual functionality makes it particularly useful in environments where both factors significantly impact product quality, such as in pharmaceuticals or food storage. The device is equipped with a wide temperature range, typically spanning from -40°C to +70°C, with exceptional accuracy levels, ensuring precise readings.

The ST-20 boasts a robust data storage capacity, capable of recording thousands of data points over extended periods. This extensive storage capacity enables users to continuously monitor conditions without the need for frequent data downloads. The built-in LCD screen provides real-time visibility into current conditions, making it easy for users to quickly assess environmental parameters at a glance.

The device employs Honeywell’s proprietary sensor technology, which enhances responsiveness and accuracy. Its sensors are designed to minimize drift and ensure reliable performance over time. Furthermore, the ST-20 features a user-friendly interface, allowing for easy configuration of measurement intervals and alarm thresholds through intuitive buttons. Users can set up alerts for both upper and lower limits, ensuring that corrective actions can be taken promptly when conditions deviate from specified ranges.

Wireless connectivity is another significant characteristic of the ST-20. It supports various communication protocols, allowing data to be transmitted seamlessly to cloud-based platforms or local servers for further analysis. This feature facilitates real-time monitoring and enables users to access data remotely, providing flexibility and enhancing operational efficiency.

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Overall, the Honeywell ST-20 is a sophisticated yet accessible data logger that meets the demands of various industries by providing accurate and reliable temperature and humidity monitoring. With its advanced features and user-friendly design, it is an indispensable tool for maintaining optimal environmental conditions and ensuring product integrity.