Red knob on high pressure side cruisair leaking

[Gusshr]

Hi Everyone,My master stateroom’s air conditioning unit keeps loosing Freon. I got two companies to diagnose, the first looked at the unit and said it is old buy a new one!The second said he filled nitrogen tested and couldn’t find a leak so he filled with R22d (R22 replacement) and he said it is cooling fine, call me again and I will fill it again once it runs empty. He said he couldn’t find the leak source.As usual I get frustrated so I do a little research and after a trip to harbor freight and $60 I got an electronic Freon detector. Turned the unit on and after 5 min read if the detector’s manual, I tested the lines and viola!!!I found the leak it is from the red colored cap on the high pressure side in front of the compressor part in the engine room. So, I thought about removing this cap and seal it and put it back again, but as I was removing it, the rest of the Freon appearing as vapor gas appeared and I retightened the cap again and working hard on finding some guidance online but I wasn’t successful.Any help of what this red caped inlet is used for? Knowing that there is the big connector on top and just above the red cap there is another cap of similar size (that’s on the high pressure side). Unlike the low pressure side which has the big top connector and only one small caped inlet.Thanks in advance.

 

[Boatsb]

Is it a Schrader valve cap?

If so probably there's a failure in the valve and it needs replacing.

 

[Gusshr]

Is it a Schrader valve cap?If so probably there's a failure in the valve and it needs replacing.

I wasnt able to see if it was a valve ( it should be). Because i wasnt able to remove the cap all the way. Gas started escapping. But my question is why there ade two cap covered valve like knobs on the high pressure side vs one on the low?

 

[Boatsb]

Pics will help.

 

[Gusshr]

Pics will help.

I uploaded my video here. Trust me that bittom cap is red (has been painted over recently). http://www.youtube.com/watch?v=7_Tb3wgvQPo

 

[Boatsb]

The valve stem is under the top cap it has a square drive. The caps cover test and service valves. Usually a scharder valve.

There's special tools available for working on them. It's also harder to work on them when charged. Call back the a.c. guy and make him make good on his service call.

 

[q240z]

I had old Cruisaire units in my Commander 42 when I got it. The PO had put a window shaker in the sliding door because the AC didn't work. I paid to have it filled with R22 and it worked great! For a few days...then it stopped. Finally tracked the leak to the shrader valves. Replaced both, and they've been working great for 5 years. Cheap fix.

 

[Reefgeorge]

First, using a refrigerant detector can take some practice. Moisture/etc can set them off so play around to get the hang of it by seeing if you get a reading around any of the other valves, especially when the unit is sweating.

Second, the white valves on both the suction/low side (left facing the front) and discharge/high side do not have schrader valves in them. They are shut off when the service valves are back seated which is the normal operating position. The extra red capped port at the bottom of the high side is to get access to the line set for evacuation and charging when the compressor is isolated and holding the initial factory charge. It has a schrader valve in it and if your leak diagnosis is accurate then the removable schrader stem and its viton seal are leaking. That red cap may just be a flare cap which mates to the port with metal to metal contact. If so, there is no bulletproof protection from a leaking schrader stem. There are caps with a rubber seal in them that can help but not in your case unless the leaking at cap removal is modest then a quick cap switch may control the situation in the short term. The permanent fix is to use a stem removal tool and replace the faulty stem. Unfortunately you would open the system, and so a fully charged system would release refrigerant which is no good. When the service valve is seated all the way to the bottom then that red capped port is only connected to the lineset and evaporator. Some guys will bottom seat that valve, run the compressor for a short bit to collect the refrigerant into the compressor and then bottom seat the suction valve. Then the amount of gas in the lineset is minimal. This manuever is not for the novice. That said, the proper proceedure would be recover the gas, replace the schraders (do them all including the sensor ports), vacuum, recharge and be on your way.

Good luck,

George

 

[Gusshr]

First, using a refrigerant detector can take some practice. Moisture/etc can set them off so play around to get the hang of it by seeing if you get a reading around any of the other valves, especially when the unit is sweating.Second, the white valves on both the suction/low side (left facing the front) and discharge/high side do not have schrader valves in them. They are shut off when the service valves are back seated which is the normal operating position. The extra red capped port at the bottom of the high side is to get access to the line set for evacuation and charging when the compressor is isolated and holding the initial factory charge. It has a schrader valve in it and if your leak diagnosis is accurate then the removable schrader stem and its viton seal are leaking. That red cap may just be a flare cap which mates to the port with metal to metal contact. If so, there is no bulletproof protection from a leaking schrader stem. There are caps with a rubber seal in them that can help but not in your case unless the leaking at cap removal is modest then a quick cap switch may control the situation in the short term. The permanent fix is to use a stem removal tool and replace the faulty stem. Unfortunately you would open the system, and so a fully charged system would release refrigerant which is no good. When the service valve is seated all the way to the bottom then that red capped port is only connected to the lineset and evaporator. Some guys will bottom seat that valve, run the compressor for a short bit to collect the refrigerant into the compressor and then bottom seat the suction valve. Then the amount of gas in the lineset is minimal. This manuever is not for the novice. That said, the proper proceedure would be recover the gas, replace the schraders (do them all including the sensor ports), vacuum, recharge and be on your way.Good luck,George

Thank you George fully understood. The unit now is almost completely out of refrigerant so maybe a quick evacuation then shreder valve replacement then a fill is the cure. I ran the testing tool to all other connections. This is the only cap that screams. There was no mousture on the cap. It should be faulty cause as i have said that backing up the cap couple turns was letting the remainder of the gas to start escaping. I just cant believe that two professional companies did not diagnose this which took me 10 min to do!!!! Do i call the second guy out or would i find a better recommendations? I am in SE florida if anyone has any good recommendations.

 

[bobk]

I just cant believe that two professional companies did not diagnose this which took me 10 min to do!!!! Do i call the second guy out or would i find a better recommendations? I am in SE florida if anyone has any good recommendations.

Reminds me of the time when a new AC system in my condo lost freon while under warranty. The service tech came out and proudly reported he fixed the problem by adding new freon. I asked if he found and fixed the leak. Duh, no, so I told him to fix it and a few minutes later he came back to report that a flare fitting was not tight enough. No leak since.

Bobk

 

[Reefgeorge]

See if Edwards Refrigeration out of Stuart will come down there. That's probable too far but he is good.

George