AC Questions

[YoungEngineer]

Hi all,
I have a 2015 Pinnacle 38FLTS. The front AC is a Coleman Mach 8, 15000 btu. Over the winter, we took it to Fl. While on the trip, the condenser fan motor mounts broke, allowing the fan to get broken. After we returned, I had the dealer repair the unit. Last week we finally tried the unit out while in a local SP. with an outside temp of 86 degrees, the interior temp was 83 degrees. Is this normal? Is this unit really shot?

[Topperace]

Does that year/model only have on AC - the Colman MACH 8 over the living area, from what I can tell from the specs?
If so, probably luck you even get 82degs in the trailer....not enough... our 383FKWS has two Mach 8s and we have to use two internal fans, and all the window blinds down during hot months to bring the temp down to 75-78 during mid to late afternoon times...also check your AC ducts/vents to make sure there are no leaks back into the roof, etc...as most RV owners have posted in some threads in one of the forums....I plan on doing that when we get out again in two weeks.... also been looking to add a 3rd AC given the size of the 383 FKWS...but the two fans have helped a lot so far...from our last two trips out...

[YoungEngineer]

No. I also have a Mach 8 13,500 btu in the bedroom. It was keeping that room at 67 degrees. Interestingly enough, I was cleaning the filters on that unit and noticed air blowing from the return. My dealer replaced that one before I bought it.

[RetiredOne]

Originally Posted by YoungEngineer

Hi all,
Last week we finally tried the unit out while in a local SP. with an outside temp of 86 degrees, the interior temp was 83 degrees. Is this normal? Is this unit really shot?

I would suggest dropping the inside plastic cover plate, and check the divider that's between the inlet and return. If that divider is out of place, or not taped securely, it won't allow air to go up through the coil and get cooled, but will just mix inlet and return air.

https://www.youtube.com/watch?v=BBzltw0e6z8

[Lake Huron]

If the main living unit is like my Northpoint there's nothing inside to pull because there is a light box covering it on the ceiling. You have to pull it off the roof. Simple enough job because I pulled mine a few weeks ago to re seal the duct work up there and fix the hot/cold divider baffle. The bedroom unit I did from the inside.
And btw, no, 86 outside and 83 inside is not normal. It took a little while but it was 90* out and my main unit, after I pulled it and resealed/repaired things got mine down to the mid 70's

[YoungEngineer]

I have a ducted installation, so there isn’t anything inside to pull on the front unit. I am awaiting a set of fin straighteners before getting backon top of the RV to continue the troubleshooting. More later.

[YoungEngineer]

So, here is the list of issues and remedies that I have found and implemented.
First, I noticed some dirt caked on the evaporator coils of the front AC. Along with the dirt, I noted some bent evaporator fins. I cleaned the dirt and straightened all the fins that I could.
Second, I found the separator partition for the hot and cold air in the bedroom unit both mangled and out of place. I straightened it and taped it in its proper position with metallic duct tape. I also noted ducts on the supply side which connect to the front ducted installation.
Third, I found the inner portion of the ceiling cover installed backwards on the bedroom unit. This I turned around when I reinstalled it.
So now, when I run both units on high speed fan unit with both thermostats set to 74 with an outside temp of 81, the bedroom unit reads 74 while the front unit gets down the 77. I have a remote reading thermometer and have checked the supply and discharge air from both units and they are virtually and same. I am at a loss as to what to do next. Any ideas?

[Topperace]

I did the same this weekend while in mountains of VA - 90 degrees
both A/Cs churning constantly and interior bedroom at 80 while living room and kitchen at 90...I also checked the bedroom A/C panels/filter/seals, added some tape...checked the front A/C from roof with no dirt/coils good, still not delivering....front kitchen is unbearable during the afternoon/early night...no temp difference from outside to inside in that area...use two independent temp gauges to check.... will be adding the third A/C soon before we attempt to go full time....I don't know how Jayco "tests" these things, but the 383FKWS can't keep up with only two A/Cs...

[JimD]

If you have a hand-held thermometer try measuring the input and output air temperatures. At best you should see a 20 degree drop from input to output. So if you have 80 degrees going into the unit (not outside temp but rather inside at the filter area) you hopefully will get 60 degrees out.

This is a good reason to start the cooling process early. If it is 75 inside the rig the output air may be 55 which makes things cooler as long as it can keep up. It is easier to maintain a temp rather than bring one down.

If the input/output temps are the same, the air conditioner isn't cooling at all.