Three A/C operation?

TXgearhead

Well-known member
It's Houston. It's hot. It's humid.
I took the Oshkosh to my RV shop to have 2 defective Carefree slide toppers removed due to a factory defect. That's a whole nuther story. Anyway, I get back home about 1 PM. It's hot. Concrete driveway, concrete street, brick house, all holding heat. No shade. I turn on all 3 A/C's. Put the awnings out. The bedroom seems to be cooling down a little after about an hour. The den was 84 or 86 inside temp. Seemed the middle vents in the den were blowing hot air. I turn off the middle A/C.
Decided it was time to read the on line users guide. It said set the thermostats to 60 and fan to auto. Did that. Ran water from a hose over the top and sides of the trailer.
What do y'all do? Can all 3 A/C's run? I thought there was a system to "shuffle?" between them to prevent overload.
First stop tomorrow is Winstar Casino in Thackerville, Oklahoma.Check in is 4pm. I ain't looking forward to it. Maybe go sit in one of their cafes until dark?
 

TXgearhead

Well-known member
It was 97F this afternoon. At 7PM it's cooled down to a frigid 94F.
I looked at the forecast and it seems there is a little "cool" front coming in tonight. Should be a high tomorrow in north Texas of 89F, with mid 60's in the mornings. I think we can handle that.
 

danemayer

Well-known member
First, you need 50 amp service to run all 3 A/C units. When on 30 amp service, the if nothing else is sucking power, you might be able to run 2 units.

Second, your PCS Energy Management System sheds loads to keep high priority loads powered. I believe power to the water heater goes first. The rear A/C unit is second. The fan continues to run, but the compressor shuts down. The PCS will automatically detect 50 amp service. If it doesn't see 50 amp, it assumes 30 amp.

Third, if you're plugged into a 15 or 20 amp receptacle, you need to let the PCS know so it understands how much power is available. If you don't do that, results are unpredictable.
 

TrailCreek

Well-known member
Out newport has three AC's and kept our unit nice and cool during the summer of '17 down in Naples Florida. It was ungodly hot, all three had to work hard as confirmed with a $200 electric bill (including water heater). Definitely 50 amp service. Maybe we'll see lower cost this year, adding 3 soft start kits.

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TXgearhead

Well-known member
Out newport has three AC's and kept our unit nice and cool during the summer of '17 down in Naples Florida. It was ungodly hot, all three had to work hard as confirmed with a $200 electric bill (including water heater). Definitely 50 amp service. Maybe we'll see lower cost this year, adding 3 soft start kits.

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But y'all were probably parked there quite awhile? If you start cooling down early in the morning it isn't much of an issue. Different when you're traveling and on the road until mid afternoon, the hottest part of the day.
 

avvidclif

Well-known member
The only thing keeping mine from cooling down in 110 deg heat is 6-8 gkids. I need a revolving door. If I plan on leaving on a hot day I turn on the AC's the night before and cool it down to the 60's. Then when I leave I run the generator and 1 or 2 AC's as needed.
 

CDN

B and B
I am wondering if you have an issue with the AC units themselves. Do you have a ammeter and check each units current. I know with being in Nashville several years ago with 100 plus our old trailer never dropped below 85 degrees at night, we had trees too. Our Landmark with 30 AC's we can hang meat in there, I had it to 50 degrees once in an hours with 90 d high humidity.

Best of luck finding what will work.

Brian
 

TXgearhead

Well-known member
I'm hoping it's because I was on the road to and from the RV shop, then back home and trying to cool down in the hottest part of the day. We'll see.
 

RickL

Well-known member
I’ve been in Yuma at 108 and never had an issue, Moab where temps hit 107, and was in the 100’s for a number of days - nary an issue. In fact, I’ve had the AC units cycle off and on during the hottest parts of the day. The only heat and humidity I have hit is probably low 90’s but humidity in the 90’s, again no issues.

The unit in the bedroom should cool it down like a meat locker especially if you close the doors. If not, I’d suspect a faulty unit.

Just my 2¢.
 

jayc

Texas-South Chapter Leaders
The trick is to keep the air on all the time. Once you get it cooled off, keep the air on. We are south of Houston, so we are well aware of the heat you are experiencing.
 

TXgearhead

Well-known member
The trick is to keep the air on all the time. Once you get it cooled off, keep the air on. We are south of Houston, so we are well aware of the heat you are experiencing.

Oh yeah, but that's difficult going down the road everyday and stopping mid afternoon.
Of course that would be an excuse for generator.
Just stopped at Winstar in Thackerville, OK. Nice and cool. 89F outside. All 3 A/C'c going. We will see.
 

TXgearhead

Well-known member
So if I'm understanding everybody...all three A/C units will run, with their compressors on, at the same time? I can get the trailer pretty cool with just the front and rear units on if I start in the morning, but the center unit is blowing only slightly cool air when running by itself. I think I have a problem with the center unit. It's pulling 13 amps when on by itself so I'm assuming the compressor is running. Only other thing on is the TV. I need a thermometer to put in the outlet vents to confirm.
 

TrailCreek

Well-known member
What if you put a hard start kit on the middle AC, add a 30 amp cable from your gen compartment to the truck bed, then run a small genset? I'm going to try this with a couple of Honda EU2000's with a companion cable. Will try one gen, or two if it needs both.

Just an idea, haven't tried it yet. I don't want to lose space in the front compartment to a full time generator.

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jmarnell

Well-known member
So if I'm understanding everybody...all three A/C units will run, with their compressors on, at the same time? I can get the trailer pretty cool with just the front and rear units on if I start in the morning, but the center unit is blowing only slightly cool air when running by itself. I think I have a problem with the center unit. It's pulling 13 amps when on by itself so I'm assuming the compressor is running. Only other thing on is the TV. I need a thermometer to put in the outlet vents to confirm.

Only 2 of the 3 units will work at the same time. On our Cyclone, the central A/C is on all the time. The power control system sheds power between the front and rear units, with one or the other compressor shutting down for a time, so only two compressors (the central and one other) are running at the same time. But the fan will continue to run on all 3 even when a compressor is not. Our mobile tech recently checked out our units, and found air leaking between the return and cold air sides of the units due to faulty tape sealing. Once he fixed that, he checked the temperature and there was almost a 20 degree difference between the cold air and the return air. That was pretty good as he said they are built to provide a 15 degree drop in temperature. So maybe your central unit has a similar problem of air leaking between the cold and return air sides.
 

RickL

Well-known member
Huh? Little confused here. While it doesn’t happen often, more after traveling for the day and starting the A/C’s to cool down our rig but all 3 A/C’s run simultaneously. Once cool they do vary when they do run.

I turn all 3 on, set the temp of each thermostats and walk away. My understanding is that the energy management system takes care of the power consumption issue.
 

TXgearhead

Well-known member
So if only 2 can run at the same time why even put 3 units on it?

- - - Updated - - -

What if you put a hard start kit on the middle AC, add a 30 amp cable from your gen compartment to the truck bed, then run a small genset? I'm going to try this with a couple of Honda EU2000's with a companion cable. Will try one gen, or two if it needs both.

Just an idea, haven't tried it yet. I don't want to lose space in the front compartment to a full time generator.

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Let us know how that works out.
 

TrailCreek

Well-known member
I should have said that the front gen set up is for when we are on the road. We want to let our pets relax in the 5'er and with two heat pumps, we hope to keep it cool or warm enough going down the road.



So if only 2 can run at the same time why even put 3 units on it?

- - - Updated - - -



Let us know how that works out.
 

TXgearhead

Well-known member
I should have said that the front gen set up is for when we are on the road. We want to let our pets relax in the 5'er and with two heat pumps, we hope to keep it cool or warm enough going down the road.
I can remember my Dad putting hunting dogs in the turtle shell (trunk) of our 1953 Chevy to go exercising or hunting. I bet yours will be OK without A/C. But whatever pulls your trigger.
 

TXgearhead

Well-known member
Huh? Little confused here. While it doesn’t happen often, more after traveling for the day and starting the A/C’s to cool down our rig but all 3 A/C’s run simultaneously. Once cool they do vary when they do run.

I turn all 3 on, set the temp of each thermostats and walk away. My understanding is that the energy management system takes care of the power consumption issue.

But only 2 of the compressors will ever be running, if I'm understanding this right.
So I don't understand why Heartland puts 3 units on the trailer.
 
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