AC temps ?

[MD3]

What temps should the AC be blowing at the units ?
Does the temps of the AC units vary depedning on the air temps inside or outside ?

I'm going to pick up a thermometer to measure the temps on both of my air conditioners. Figure I will check them at the vents on the AC unit itself.

I'm wondering if I have a problem with my rear AC unit or if it is just too hot outside for it to cool down as much as I would like.

2018 Seneca

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[Midnightmoon]

The differential is measured from input air temp. Normally, output should be in the 20 degree +/_ range from that input air temp.

[Oma/opa]

+1 on the 20 degrees

[Camper_bob]

I think I remember reading somewhere that the temp differential is within "spec" according to Coleman at 16 degrees or greater delta over the coils.

Most people reference 20 degrees delta over the coils to be as good as it can get.

FWIW, I believe my problem with my front unit has to do with the area being cooled. The rear unit is the same size as the front, but it's handling about 1/3 the cubic area as the front unit. On top of that, the front unit has to fight the cab area, the door, and the huge windows over the couch and dinette.

[Route 66 Traveler]

Spend some time and read through these posts:

https://www.jaycoowners.com/forums/f...ing-67173.html

[Mountain Cajun]

Dump the rear air directly into the room, not in the ducts. My rear air will freeze you out! But I don’t know what year but Jayco went to a 13.5 btu rear air.

[jd99336]

I am on the OK, TX, NM, AZ phase of our long trip in our 31DS with only one AC. I was very concerned with cooling. In fact, the 15K BTU unit seems to be holding up well. We have had multiple 100 degree days and as long as we get the unit started, close up the window shades, it will eventually lower the inside temp from 99 to 80 over a couple of hours and maintain it.

In two days we transition to Bryce Canyon and lower temps....

[MD3]

Thank you for the information !
I will do some air temp measuring at the intake and at the vent where the AC dumps out.

Our last older class A had two smaller AC units and would freeze us out. The Seneca has two larger units and will cool down but nowhere near freezing us out. Class A was even a little larger floor plan.

I also think the Seneca is not sealed as well as our older class A and that may contribute to it as well.



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[RetiredOne]

You also might want to go check out this thread, it will give a bunch of tips on the ducting. It seems that quality control and A/C install are severely lacking at Jayco, the way they install ductwork and the divider between the air return and output.

https://www.jaycoowners.com/forums/f...ing-67173.html

Some simple clean-up has made a world of difference for some people here, depending on how sloppy the install was.

[rkymntsno]

Four months of ownership in our new 355 mid-bunk. We have the whisper quiet a/c and the front loud a/c 13,500. I complained to the dealership the big living room unit wasn't cooling like I thought it should. They said they checked it out and was working fine. Mid-afternoon here in Port Aransas, temps not going down, going up. Creeps up to 75, 76 but with the heat indices this week, I guess it's doing good. All vents have good cold air blowing. I shot a temp gun and they're blowing 44 degree air. Guess it's too hot outside and I have a large rig to cool down.

[SloPoke]

it depends on which unit you have...

From the Airxcell web site:
An ideal cooling system should give you an output temperature range of 16-22 degrees lower than the temperature taken in at the filter. Humidity is a significant determining factor in this temperature difference.
You can test the temperature difference by taking a reading at your filter and the first register where air is leaving the system. Please use the same thermometer at each location.

The higher the humidity, the harder it is to cool the air. Also the condition of your condenser and evaporator coils have a lot to do with it.

Keeping our Seneca cool in the HOT SUMMER SUN is all a matter of how much sun is beating on the sides of the Seneca. We try our best to orient our rig facing East. That way the morning sun rises on the Cab that has poor insulation.. then the sun will slowly expose the passenger side that can be shaded by the Awning. The back cap of the Seneca has some air-gap along with the wall insulation - that gets pretty warm in the late afternoon, but we are rarely back there - we just close the bedroom door with our 15k AC running.

[JimD]

Just spent the weekend at a campground where the outside temp was just over 100. When we arrived and turned on our 2 ACs in the Greyhawk, the inside temp was in the upper 80s. The temp never did get down below 84-85 inside that day. It didn't help with people constantly opening the door.

The second day we started both units mid morning when it was 75 inside. The unit remained cooler throughout the day. I think the highest it went was 76. Very comfortable!

The trick is to start cooling before it gets too warm inside. It is easier to try to maintain a lower temp rather than having to drop 10-15 degrees.

[Camper_bob]

Originally Posted by JimD

Just spent the weekend at a campground where the outside temp was just over 100. When we arrived and turned on our 2 ACs in the Greyhawk, the inside temp was in the upper 80s. The temp never did get down below 84-85 inside that day. It didn't help with people constantly opening the door.

The second day we started both units mid morning when it was 75 inside. The unit remained cooler throughout the day. I think the highest it went was 76. Very comfortable!

The trick is to start cooling before it gets too warm inside. It is easier to try to maintain a lower temp rather than having to drop 10-15 degrees.

+1

Remember that these AC units work on temperature delta. It can only cool the air 22 degrees at best (mine are more like 16-18 degrees?). So if the coach air is at 100 degrees, the best you can possibly hope for air temp at the closest vent to the unit is 78. And that's if everything is optimal. These things aren't insulated well at all as most of us already know, so that certainly doesn't help matters. And I'm betting that the temp delta at the furthest vent from the unit isn't great because the duct basically sits right below the roof.

It's MUCH easier to KEEP a rig cool than to GET a rig cool. I've even gone so far as to turn the temp down in the mornings on hot days to give the AC units a head start on keeping the coach cool during the hottest part of the day. DW gripes at me constantly, accusing me of trying to freeze her out!

FWIW, my biggest challenge is my counter-top ice maker. I love that thing, but it can put out some HEAT. It's like constantly running a hair dryer in the coach. Also, for those of us in motorhomes, the more you can isolate the cab area, the better. Even that silly sheet that comes with the unit makes a difference. I always put a white "mask" over the windshield and doors. Between the mask and the sheet, it helps quite a lot.

[Mountain Cajun]

I’m sitting here in my 2016 HJ Topaz paint scheme (mostly black) Seneca in Cañon City Colorado with no shade! I have both a/c’s set at 70. Outside temp is 100 degrees. Cab windows are covered with Heat Shields. Inside temp is 78 degrees. Beat it will do! I’m just glad I’m not getting off the road now. I’d never get her cooed down!

[MD3]

I watched the links and pulled the inside panel off my AC’s. Both are already tapped inside and the divider is perfectly placed.
Checked intake and output air and it right at a 20 degree difference.

I’m thinking I’m loosing my cool air through the numerous lack of sealing the coach. I found an open 4” hole under the shower. Numerous 1” holes behind the cabinet through the floor.... no telling where else I’ll find holes and air leaks.


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[SloPoke]

Originally Posted by MD3

I’m thinking I’m loosing my cool air through the numerous lack of sealing the coach. I found an open 4” hole under the shower. Numerous 1” holes behind the cabinet through the floor.... no telling where else I’ll find holes and air leaks.

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Don't look behind your outdoor TV with the door open. Ours backs up to the Kitchen Sink cabinets... and when we open a cabinet, you can see outside.

[Tcdoughboy34]

From a dealership perspective, the AC is only designer to change the air 15 degrees and no more

[ralett]

We just got back from 7 days in 115+ temps at the Colorado River. We did this trip last year and could not get our 2018.5 Seneca below 90 degrees inside until the sun went down. Even then, it ran in the high 80's inside with both ACs running on Hi Cool.

I went though all the threads referenced earlier and fixed all the plenum/ducting issues on our AC units (the install was completed jacked with the plenum separator on the front AC unit laying almost flat, blocked ducts, torn plenum liners, etc.). Making these fixes made a huge difference.

I also rigged up a portable AC unit (10K) which sits between the front seats and ducts out through the passenger window. I set this up once we were parked and ran a separate 120 AC cord to the power box.

With that setup, we ran 73 degrees inside the rig when it was 115+ outside, and we had full sun, no shade at all, with the rig parked facing south.

At night, with an outdoor low temp in the high 80's, the rear AC unit was off more than it was on. The front units ran all night long.

My take is in the extreme heat, the Senecas just need more AC in the front to keep the rig really cool.

[greyhawktom]

when I am in florida this time of year I turn the air down to 74 in am and by 2pm its

usually around 81 , 82.
Its a 2015 greyhawk fk with one air. The fact that it has dark brown paint doesnt help,
plus the humidity.

[solocanoejake]

I have an Eagle 33rets tt. I checked with the dealer about the temperature change in the trailer. He says the manufacturer allows a six degree fluctuations at the thermostat. In Florida, the extreme temps during the day do cause the outlet temp to rise because the air going across the condenser is higher.
My trailer should have a second a/c unit. I keep the bedroom door closed. At night I close living room vents. This does help a little.