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m.hony · 08-06-2016, 01:36 PM

Our A/C quit working- both units.
I suspect the thermostat.
The Dometic CCC2 (?) thermostat was displaying an error message E1.
When attempting to reset, zone 1 and 2 went away and it shows zones 2 and 4 but will do absolutely nothing.
The owner's manual is no help.
I suspect the thermostat or mother board. I suspect there is no "communication" between the thermostat and A/C units.
I wonder if there is a better way.
1 thermostat for 2 units is a fatal design flaw in my opinion.
Having a programmable thermostat in a camper is just stupid in my opinion.
Is it possible to have 2 simpler thermostats?
All I need is the old timey kind like on a home system- heat, air, fan, temperature- simple on/off.
Simple- bi-metal spring and a Mercury switch-
I want 2 separate thermostats so that when the one thermostat quits you don't lose both A/C units.
The bedroom needs its own.
The living room needs its own.
Is it possible to install 2 less complex more reliable thermostats with the Dometic units?
As it is, we are cutting our trip short and going home.
Not a thing I can do about it today-
As with everything about a camper that quits, breaks, or fails, you never discover it until Friday night or Saturday afternoon.
I have no clue how to proceed except to try to get to an RV dealership.
I am geographically challenged.
There is no RV dealer or repair shop for 100 miles.
Also, I work-
I work at the same time the dealerships are open for business.
So I may have to schedule an appointment and take off work.
The dealers never have parts on hand and have to order.
They want you to drop off your trailer and leave it for 2 weeks.
I can't be without the trailer that long.
The nearest Airstream dealers are 4-5 hours away.
So I would make an 8-10 hour round trip to drop off the trailer, then the same 8-10 hour round trip to pick up the trailer and have to cancel a couple of events.
I might have to take off and go to Jackson Center, where they will have parts on hand and will fix it while I am there camping in the Terraport.
Thoughts?
Advice?
Wisdom?

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HowieE · 08-06-2016, 02:37 PM

There is NO reason to have to take it to an Airstream "stealer" unless it is under warranty. Any RV dealer that has a qualified shop can fix it. It first sound like a programming error if it is showing units 3 and 4 while you only have 2 units.

You might call the AC maker and see if they have instruction they can e mail you and you might be able to reprogram it.

lewster · 08-06-2016, 02:42 PM

Depending on exactly which Dometic units you have, you may be able to replace the CCC-II thermostat and control systems with individual Dometic 'Single Zone Thermostat' systems.

These would give you a digital thermostat for each unit, along with furnace control from one of the units and heat pump control for both.

You will need the complete kits (if they are compatible with your units) as each unit will need the new thermostats and control boards that go with them.

Lew Farber

Hiho Silver · 08-06-2016, 02:46 PM

Not sure how you reset your thermostat, but you could try unplugging the telephone cord connection on the back of the thermostat, if you didn't already do this?? Pull the thermostat carefully off the wall, then unplug the cord for a minute or two. I figured it maybe worth a try for your situation. Thats how a tech at JC told me to reset my thermostat, on my 2016 FC.

m.hony · 08-06-2016, 02:54 PM

I will try that.

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m.hony · 08-06-2016, 02:59 PM

ALL RV dealers are a rip-off as far as labor rate, and there are none for 100 miles.
The only somewhat reputable RV repair shop is still 80-90 miles away.
All would require an appointment or leaving the trailer.
I will still have to take off work to tend to it if I don't figure it out.
91 degrees here...

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m.hony · 08-06-2016, 03:05 PM

OK, guys...
This is getting stranger...
I took the thermostat off the wall and unplugged the telephone cord and plugged it back in.
The living room a/c came on... But on Zone 4!
Wth?

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m.hony · 08-06-2016, 03:08 PM

It won't turn off.
It will not show the bedroom unit- only zone 4-
None of the switches do anything...
But the living room a/c is blowing- regardless of what button you push...
I still suspect a bad thermostat...
Monday I will try calling Airstream, dealers, and Dometic.

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RonaldC303 · 08-06-2016, 03:36 PM

Here is the procedure for resetting with an E1 error code:

https://rvseniormoments.files.wordpr...r_recovery.pdf

Sorry, the insert link function is not working.

Ron

m.hony · 08-06-2016, 04:36 PM

Tried that several times.
Nothing works.
Error code is gone.
It shows zone 4.
None of the buttons will do anything.

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Wingeezer · 08-06-2016, 05:33 PM

Can't help with specifics but share your pain!

We only have one AC but have had a lot of control problems with it. At the moment it is ok!

I did find a troubleshooting guide someplace on the internet for that thermostat control - I think ours is the same as yours, it is a five button control. I'm sure you could find it with a google search if you don't already have it

Initially when we had problems I found whitish corrosion on the back of the thermostat circuit board. Cleaning it with alcohol and Q-tips got things working again.

A year or two later I started having more erratic problems. This time it seemed associated with the connecting cables or the female-female cable splice adapters that they plug into under the AC grille.

I had one spare connector hanging down (for a second AC unit if used I believe) so I switched and plugged the cable from the thermostat into the second unused one instead and things started to work!

It has been that way ever since and still working!

My feeling is that those cheapie telephone-type connectors might not be the best for this sort of service. I'm hoping I don't have further problems!

One thing to note if you consider trying to replace the cable to thermostat is that it looks like a standard four wire phone cable - but it is not. The plug at one end needs to be reversed 180 degrees on the cable compared to the plug at the other end. It is a data cable.

I learned that from Lew who give me several very helpful tips!

I am not sure if the cables that run up from the hanging connectors through the ceiling and up to the control board on the AC are reversed the same way or not - maybe Lew can comment if he happens to read this!

In any event I now carry spare cable, phone type terminal jacks to crimp on, and the special tool to connect the terminal jacks to the cable with me just in case I have further problems and need to mess around trying to make replacement connecting cables on the road! Hopefully having this equipment along will ensure I never need it - usually i goes that way!

I think the cheap little female - female cable splice connectors under the inside grille can be suspect also, and I carry a couple of spares of them.

Beyond that I have considered buying a spare control board and thermostat to carry with me. Last I checked they are still available. But they are about $100 each on line I think and I have not done that yet!

Good luck! Like you I wish they would just keep these things simple for us poor owners!

Brian.

perryg114 · 08-06-2016, 05:40 PM

I suspect both units can be downgraded to a simple mechanical thermostat. The bad news is the Dometic mechanical thermostats are terrible. I am using a 35 yr old coleman thermostat that came on the unit that came with the trailer and all my problems went away. There is no reason it could not be hot wired with a simple switch till you get it sorted out. It would be all or nothing. Open some windows to adjust temp and watch out for freezing up if running 100% of the time.

Perry

CruizinDux · 08-06-2016, 06:38 PM

m.honey, on the first night of our maiden voyage last winter, were in a friend driveway w/SP. I turned on the furnace, the gas fired, then the AC fired.

I noticed in the manual two references to hard boots to the factory defaults. Ours in a 2014 so the CCC2 stat may not be the same.

This operating instruction I just picked up off the web and is a bit different in page display. The system re-set is on page 11. On my manual it is on pages 4 & 20 but contains the same procedure.

It worked for me...we had heat that night...without the AC. I should also say we have never used the HP for either heat or AC mainly due to the noise, but plan to dive in on our fall trip to MO.

Bob

ijustlee · 08-06-2016, 07:14 PM

I hate electronic control boards on things! Maybe you could hire a local AC heating tech to convert the AC units to simple individual thermostats? Kinda hard to find one who really knows what to do but tell them you won't pay until the job works like you want. Unfortunately here in California you can't buy a thermostat with mercury contacts anymore! The mechanical ones work good if you keep the contacts clean though, I check mine for lint once or twice a year.

m.hony · 08-06-2016, 08:04 PM

Quote:

Originally Posted by CruizinDux

m.honey, on the first night of our maiden voyage last winter, were in a friend driveway w/SP. I turned on the furnace, the gas fired, then the AC fired.

I noticed in the manual two references to hard boots to the factory defaults. Ours in a 2014 so the CCC2 stat may not be the same.

This operating instruction I just picked up off the web and is a bit different in page display. The system re-set is on page 11. On my manual it is on pages 4 & 20 but contains the same procedure.

It worked for me...we had heat that night...without the AC. I should also say we have never used the HP for either heat or AC mainly due to the noise, but plan to dive in on our fall trip to MO.

Bob

Same thermostat-
Same manual-
2013 trailer-
Reset procedure does not work-
Now...
No a/c and display has zone 1 flashing and zone 4 not flashing-
This started with the reset procedure in a he manual.

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lewster · 08-06-2016, 08:18 PM

Along the lines of converting an A/C unit from electronic operation to use of a manual thermostat, given all of the functions that are required of the control board, factoring in things like evaporator freeze control, multi unit compatibility and use of the A/C, heat pump and furnace functions, I seriously doubt that any conversion of the type could be successful.

Also, don't forget that any control system that requires more than a phone-type data cable will require new wiring from the t/stat location to the A/C unit. Good luck with that!!!!

I have had to replace control systems several times in larger motor homes, but they were for RVP/Coleman units and required both new control boards, thermostats AND complete system re-wiring.

Luckily, these units had common duct work that provided the path for the new wiring, and the thermostat location was also easily accessible and in close proximity thru an adjacent closet.

Airstream trailers offer very few of these requirements.

If m. hony is having communication issues between the upper control boards and the t/stat, first place to check is the cheap plastic unions that join the data cable running from the t/stat to the upper control board.

If you have Airstream's ducted system, this will be difficult to access as there is no real 'ceiling assembly' to remove. You might be able to gain access by removing the air return grill on the curb side, located directly below the unit.

Best bet would be the unit closest to the t/stat, as this has a high probability of being the Zone 1 master unit where the initial connection is made.

I would also be armed with several RJ-11 unions for the purpose.

Lew Farber

Sjcjr · 08-06-2016, 09:48 PM

Quote:

Originally Posted by m.hony

Tried that several times.
Nothing works.
Error code is gone.
It shows zone 4.
None of the buttons will do anything.

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I had a similar problem with my previous airstream. Try killing ALL power. Unplug electrical AND put battery disconnect in the store position. Wait ten minutes. Plug in shore power and see if proper communication is re-established between both ac's and thermostat. It worked for me.

m.hony · 08-07-2016, 03:20 AM

I guess it's worth a try.
I got nothing to lose.
I just don't get why we need a programmable thermostat in a camper.
It just needs on/off, heat/air, temperature, and fan like an old timey house thermostat.
Even if it has to have fancy electronics to communicate with the mother boards on the units it could still be simpler/less complex-
Bi-metal spring and a Mercury switch...

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m.hony · 08-07-2016, 03:22 AM

I also don't get why we need 2 units to run on 1 thermostat.
If the thermostat quits, both units are down.
It would make so much more sense to me for each unit to have its own thermostat.
Why has it got to be so complicated?

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djarrett · 08-07-2016, 06:48 AM

I found this info on another forum:

Here is how to fix the most common dometic thermostat problems for the 4 and 5 button Comfort Control thermostats. Dometic support is awful and there are a lot of folks out there spending large sums of money on new thermostats and upper board conversion kits. With this posting you can save yourself big bucks.

I am a geek and figured it all out. There are procedures here you will not find anyplace else.

Below are the 3 most common problems and the way to fix them.

AC UNITS TURN OFF WHEN GOING OVER BUMPS, THERMOSTAT WILL NOT TURN ON, OR WILL NOT STAY ON:

-- The on/off switch on the thermostat probably has cracked solder joints. Re-solder the switch to the board and make sure the switch is snug on the circuit board so the solder does not crack again. Use a small 25-watt soldering iron with a finer tip on it. Of course, use electronic solder, not the solder used from plumbing! (Note: Dometic boards are famous for cold solder joints -- you might need to touch up the other solder points -- but don't try to do the microprocessor unless you know what you are doing.)

-- Also, soak the power switch with spray contact cleaner and operate the switch a few times.

-- If the above does not work, you might need to take the switch off the board, take it apart and fix it (you won't find a replacement for this switch on the internet due to the long paddle on it).

-- These switches were not properly mounted to the circuit board in the first place. You might have a cracked trace on the circuit board, which can be fixed by carefully scraping the green backing off the board with a small razor knife and soldering a small piece of solid wire (such as telephone wire) across the crack.

PUSHBUTTONS DO NOT WORK PROPERLY

(Note: the logic on the board triggers functions when a button is released, not when it is pressed. You have to let go of the button before a function is processed.)

Clean the switches. Remove the PC board from the housing. Do this in a clean work area so you don't lose any parts. Using a small flat jewelers screwdriver, carefully prise the locking tabs holding the top of the switch on the base JUST ENOUGH to pull the top of the switch off. Be sure not to lose any parts. Clean the contacts with spray contact cleaner and perhaps Q-tips. Snap the top back on the switch.

TEMPERATURE SENSING PROBLEMS:

First you have to understand how the system works.

For zone 1, the thermistor (little yellow thing near the thermostat on/off switch) inside the thermostat is usually used. If a remote sensor is plugged into the AC unit upper board (the white 2-pin plug), then the remote sensor is automatically activated by the thermostat and the temperature sensing electronics inside the thermostat is disabled. Do not bother trying to fix the electronics on the thermostat. It is complicated nonlinear circuitry and can't be fixed since Dometic provides no documentation.

Zone 2 usually has a remote sensor wired to the rear upper AC unit board. The temperature is processed by circuitry on the rear AC upper board. Look for a white nylon 2-pin connector on the upper board to see if a sensor is connected to it.

NOTE: In both cases, if a remote sensor is used, the electronics on the upper board are used to read and process signals for that zone from the thermistor. If communications between the boards and thermostat are hung up, it won't work right and there is no telling what it will do.

NOTE: If you are going to unplug the thermostat from the phone connector, always turn the thermostat off first, and also be sure the thermostat off before plugging the connector back in. If the thermostat is on when you unplug it or plug it back in, communications will not establish.

For testing, you need a thermometer from around the house so you can see what the real room temp is. Use a fan blowing on the home thermometer and the thermostat so you don't have to wait all day for thermostat and thermometer to sync up.

Dometic says these thermostats are accurate to +/- 5 degrees, which is abysmal. My experience is that they are usually within +/- 3 degrees (lousy). You will probably have to live with it if your thermostat is in this range.

If your thermostat isn't turning on/off at the right temperature (+/- 3 degrees), here is what to do (in this order):

1. Clearing communications issues: your unit can get into a situation where the thermostat is not communicating with one or both upper boards. Turn the thermostat off, and turn power to the AC units off and on. Then turn the thermostat on and see if it works better.

2. Reset the thermostat to factory specs. This can correct some problems with invalid temperature measurement when the thermistor inside the thermostat is being used. This sequence definitely works with 4-button thermostats. I do not have a 5-button unit to test so I cannot say if it works on 5-button thermostats. Do the following in the order below:
-- Turn the thermostat on
-- press any button once
-- press and hold the bottom 2 buttons in
-- press and release the mode button one time
-- release the bottom 2 buttons
-- press and release the mode button
-- if you did the above sequence correctly, the thermostat backlight will turn off. If it does not turn off, do the above sequence again.

3. Rear unit: If the temperature setting still does not work right, the problem is in the upper board (not reading the remote sensor thermistor correctly). Get a new upper board (available on the internet)

4. Front unit without remote sensor: Since the thermostats are no longer available and the circuitry not repairable, install a remote sensor 3106486.008 in your front AC unit. Just plug it into the upper board and the thermostat will use it. You will have to figure out how to route the thermistor down into the RV. If this does not work, the upper board is bad and needs to be replaced.

2. Front AC with remote sensor: Either the thermistor sensor is bad, or the circuitry on the upper board is bad. The sensors rarely go bad, but you can check the sensor with an ohmmeter. Unplug the sensor from the white plug on the upper board, and measure the resistance. The resistance should be about 7.2k at 70 degrees, 9.8k at 60 degrees, or 12.4k at 50 degrees. If you are seeing no resistance, then the thermistor is definitely bad If the thermistor is good, replace the upper board.

2. Reset the thermostat to factory specs. This can correct some problems with invalid temperature measurement when the thermistor inside the thermostat is being used. This sequence definitely works with 4-button thermostats. I do not have a 5-button unit to test so I cannot say if it works on 5-button thermostats. Do the following in the order below:
-- Turn the thermostat on
-- press any button once
-- press and hold the bottom 2 buttons in
-- press and release the mode button one time
-- release the bottom 2 buttons
-- press and release the mode button
-- if you did the above sequence correctly, the thermostat backlight will turn off. If it does not turn off, do the above sequence again.

This has NOTHING to do with temp sensing issues. ALL this does is reset to the TEMP preset on the tstat (usually 72 degrees and just verifies the DIP switch settings on each control board. NOTHING else. A LOT of people think the reset is like resetting a PC. It is NOT. It does NOTHING for operational issues. As to your assertion that people are spending money when the system can be fixed. You are correct, but at $125 per hour average labor, It would cost HUNDREDS of dollars to do all things you have suggested with no guarantee that the system will function after it is done. Now, if you have the tech smarts you have, then it is worth the time and effort. MOST rv'ers do not have the knowledge and expertise to do what you did. Besides, 4 button systems were discontinued almost 13 years ago, so paying someone to do that work is not cost efficient.
________________________________________________

Hope this provides some solutions to your problems
Dendy