Posted 22 October 2019 - 10:23 PM
Unless you have some training or decent experience, it’s not as easy to get right as it may seem. It’s also illegal to release the gas into the air. If you replace the compressor, you need to ensure the correct amount of oil is in the system. If you replace the compressor or the TX valve, you have opened the system, and should pressure test it with nitrogen to ensure no leaks. Nitrogen also helps pull any moisture out of the system, as even small amounts will freeze and block the TV valve, stoping refrigerant flow. After nitro test, you need to use a vac pump for at least 12 hours to empty the system of all nitrogen and moisture before re gassing, being careful not to introduce any air/moisture.
134a is very expensive now, as per IT’s link, about 70% govt tax to fund a program to have used gas destroyed safely, after its sucked out of systems with a special and expensive refrigerant reclaim machine.
Realcold refrigeration stock the TX valves, you’ll need the valve and an orifice to match, correctly sized for your system, it then needs adjusting once installed to make the system run the right pressures and have the right amount of flow. Don’t forget you need to change the drier and sight glass once you’ve had the system open.