CruiseAir Temp Difference

[Ck2hans]

My Front CruiseAir unit is seeing a 10-to-12-degree difference between the intake vent and outlet vents in a shaded garage with outside temps of 80 deg. Somewhere back in the old fussy brain cells I think I remember the temperature difference should be 20-to-22- degrees if the system is working properly.
Can someone confirm or deny these numbers.

Chuck

[Fratto]

Not sure about CruiseAir specifically but yes, 20 deg would be good. A 10 degree delta will never cool your coach.

[Ck2hans]

Started looking deeper into things because the front CruiseAir has never really cooled well, even after having the unit behind the bumper replaced. Found the copper line (larger one) going into the evaporator in the front cabinet has been bent to tightly and has quite a kink in it.
Not all the knowable on AC systems but have to imagine that kink is reducing the freon flow and in turn effecting it's overall performance.

Chuck

[DaneB]

Chuck
What are your pressures on the front unit? A slight kink in the suction line should not affect it much, but a significant kink will. That kink was likely there the whole time, but now that you are searching an issue you noticed it and could be the culprit. Can you post a picture of the kink? The front evaporator plate (inside the coach behind the mesh filter) should feel wet. With a 10-12 degree split as you state, it likely is low on refrigerant. Check your pressures and adjust accordingly. If the kink is the culprit, it will also reflect in your gauges, primarily with a erratic or bouncy reading. The kink will cause it to improperly meter the refrigerant and pressure fluctuations in the gauges. The low pressure should be around 55-65 and high pressure should be around 225-275. This range is relative to your current ambient temp.

[Ck2hans]

http://forum.prevostownersgroup.com/attachment.php?attachmentid=18304&stc=1

Dane:

Here is a picture of the Kink. I am the 3rd owner, when going through the paperwork I noticed lack of cooling in the front unit (The one I found the kink in) has been a complaint since the first owner. Compressor failed shortly after I purchased the coach 3 yrs ago. Had AAP in VA replace the front unit. It cooled but never that well. Think I discovered the reason why it has never cooled well. Hopefully before it has ruined my new compressor.
Not going to be easy to access, buried under flooring that's under the cabinet.

Chuck

[Fratto]

Good catch. You are right, there is no way that this will allow the system to work at its rated capacity.
Keep us posted on performance after you correct this problem.

[Ck2hans]

Update:

Finally finished my contacted job and got back to the bus project. Had Dana from AAP (working out of Tradewinds in Deland Fl) check the system, he said all the pressures were OK and recharged the system. It worked fine for awhile then started getting warm again. Unfortunately Dana no longer works for AAP and rumors have it that AAP is out of business.

Just got back from Tradewinds, their AC tech did a thorough checking of the system isolating the evaporator and then the condenser checking for leaks or restrictions. He found the flex tubing on the front swing out unit was leaking. Replaced the hose and charged and check the system. All seams well.

Both Dana and Tradewinds tech looked closely at the kink and tested for restrictions by referencing the PSI differences on their gauges. Both guys said they have seen more severely bent tubing without issues and from the results of the PSI gauges they felt my kink was a non issue.

Fingers crossed, unit cooling nicely.

Chuck