英语论文网

round 20 C) you must initially consider it to have a leak. The only approved method of diagnosing a system that is open to the atmosphere is by using Oxygen Free Nitrogen.
记住这句行话：“严禁蓄意释放制冷剂。”所以在系统中充入几百克的制冷剂，观察它是否泄漏会被处以重重罚款。如果系统是空的或气压很低，如在20℃时气压低于2巴，你必须首先考虑到其中发生了泄漏。诊断一个与空气相通的系统，唯一认证的方法是通过无氧氮气。
Oxygen Free Nitrogen (OFN) 无氧氮气（英文简称OFN）
Nitrogen represents 78% of the atmosphere and it’s what makes the creamy head on some beer, so it’s safe. The reason it’s oxygen-free is that oil, oxygen and compressors are a good way to make an explosion. Think of a diesel engine.
氮气占空气总量的78%。一些啤酒上的奶油般泡沫也是氮气生成的，所以它很安全。要求无氧的原因是，汽油，氧气和压缩机三者组合会产生爆炸，柴油机就是个很好的例子。
To test for leaks the system is pressurised to 10 bar (147 psi). A major leak will be apparent by the noise it makes. If no leaks are apparent, a valve is closed and the pressure in the system is monitored using the equipment gauge. An ultra-sonic leak detector can be used to detect smaller leaks. There are a few on the market but reviews are mixed. An electronic leak detector may find any residual traces of refrigerant or oil forced out by the increased pressure of the nitrogen. Small leaks are best found by using soap and water in a sprayer and looking for bubbles. Don’t forget to check the service connectors.
要测试泄漏，系统的压强需设定在10巴，即147 psi。一个大的泄漏很产生很大的噪音。如果没有明显泄漏，关闭一个阀门，使用设备规范来监控系统的压强。可以使用一个超声波检漏器来检测较小的泄漏。这种检漏器市面上有销售但是人们对于它的褒贬不一。一个电子检漏器能够发现任何由于氮气压强升高而被挤出的制冷剂或汽油残渣。小的泄漏可以通过装在喷洒器中的肥皂水来检查，如果发现气泡，说明有小的泄漏。不要忘记检查服务连接器。

If the leak is very small and in an area you can’t get at, around the evaporator for instance, they can be very elusive.
如果泄漏很少，并且发生在你无法够到的区域，比如蒸发器附近，那么你会很难发现它们。
If a leak cannot be found then it must be assumed that there isn’t one.
如果找不出泄漏，必须假定没有泄漏的情况。
Vent the nitrogen to atmosphere and vacuum the system for 30 minutes to remove any moisture. Now charge the system with refrigerant and introduce 5-10ml of UV dye.
将大气释放在空气中，将系统抽成真空，保持30分钟来去除所有水分。现在在系统中加入制冷剂，并加入3-10毫升的紫外线着色剂。
Remove the service hoses and check using an electronic leak detector, especially around the service connectors. Run the system for 10 minutes for the dye to mix and circulate and check for leaks using a combination of the UV lamp and goggles and an electronic leak detector. If a leak is discovered at this late stage, recover the refrigerant and fix it.
摘除服务教官，使用一个电子检漏器检查，尤其是服务连接器周围。运行系统10分钟，保证着色剂充分混合进去并开始循环。使用紫外线灯和护目镜，还有电子检漏器检查泄漏。如果在这个阶段才发现泄漏，回收制冷剂，维修系统。

Electronic Detectors 电子检测器
The electronic leak detector is an absolute must for any technicians using AC servicing equipment. When a system has been serviced and the service connectors removed, the service port should be blown out with compressed air and checked for leaks. (I have recharged many systems over the years and have come across lots of leaky Schrader valves). A good detector when used properly will show up the smallest of leaks with pinpoint accuracy. One thing to remember: R