AC 問題解決，答謝和點滴經驗

 

感謝車族朋友追風大老虎，x88,  MoonRiverttt , JunkYarDDo, SmallBlock, and my friend NG, 提供寶貴知識經驗. AC 問題解決！Root cause 是最簡單的冷媒不足. 以下是學習經驗點滴：

 壓縮機無法啟動時加注冷媒：

There are probably at least two ways to add refrigerant when the compressor is not running; One is to vacuum your system to create pressure difference between the refrigerant can and the system. Without a vacuum pump, used 追風大老虎 曲別針大法  - a jumper to bypass the pressure checking, so that compressor can be turned on to suck the refrigerant in. This works great in my case. And of course, you must have a secured jumper. See picture.

 

低壓端零壓力，高壓端低壓力的情況處理：

This is a typical case of refrigerant not circulating well based on the service manual. But my case is a bit different, while the low side reading is zero, the high side reading is less 20 psi, indicating insufficient  refrigerant also.

Thanks again to my friend NG and 追風 for encouraging go on to add refrigerant; and this resolved the problem. After first 13oz can added, the pressure back to about 50psi high side; and this apparently is going over the pressure switch threshold, so removed the jumper and put the pressure switch plug back to the system, the AC on and compressor running! Added second can, and the pressure is about 14psi and 60psi now when the compressor is running, they are all still too low.

The system has capacity of 37oz, so I will need the 3^rd can refrigerant. Leave this to next month when temperature is higher; Also give me a chance to check if there is any leaking.

 工具：

Manifold Gauge Set  is a must-have tool. Plus don’t like this plastic coupler comes with the refrigerant can! It is very hard to plug onto the low side port! Ended up using my friend’s metal type coupler with the charge hose, see pictures.

You can also charge refrigerant thru the yellow hose of the MGS, but I didn’t use it because didn’t vacuum the system, so a shorter (12” vs. 70”) hose with less air in the hose, is better .

 Again as one of friend here mentioned, AC system is tricky so don’t do it until you totally understand what you’re doing, at the very least, have the tools and the service manual.

 

What does a leaking look like from UV light picture.

所有跟帖： 

• 這個一定要頂。謝分享！ -SmallBlock- ♂ (0 bytes) () 03/10/2013 postreply 13:53:36

• Thanks for the support. -Gulang- ♂ (0 bytes) () 03/10/2013 postreply 18:53:29

• 這隻是暫時的，你要找到哪裏漏並fix，否則明年你還要再做一次 -giddyup- ♂ (0 bytes) () 03/10/2013 postreply 15:22:39

• Agree, thanks. Hope the UV dye would give me some clues. -Gulang- ♂ (0 bytes) () 03/10/2013 postreply 18:09:49

• 我懷疑你的R134A已經加多了.你高壓端運轉是多少psi? -滿地找牙- ♂ (654 bytes) () 03/10/2013 postreply 16:41:55

• 謝謝滿地找牙支持！My bad, should mention 54psi (or 64psi later) is 。。。 -Gulang- ♂ (182 bytes) () 03/10/2013 postreply 18:16:38

• if your car is 10 years old, many places on a/c could be leakin -giddyup- ♂ (371 bytes) () 03/10/2013 postreply 22:02:22

• Very helpful info. Thanks. It is 14 years old, so far no obvious -Gulang- ♂ (105 bytes) () 03/11/2013 postreply 17:53:32