AC issues

Greg Strban · 08-15-2023, 06:14 PM

I have a 2010 Keystone Alpine 3500RE. Early this year was getting E-1 code on thermostat. Mobile rv guy came and looked and we found some bad splices where a company had replaced the roof and did a horrible job or removing and replacing unit. He told me they both should work fine but heat wouldn’t work until I replaced the control board. I replaced that and was still getting code. Family came and looked (ac certified) and we somehow managed to get both acs to come on at same time and could not separate. Still no heat. Buttons on thermostat were acting funny and he recommended a new one. I installed a new thermostat and code is gone and still not working right. A friend (ac certified) came and looked today for a couple hours but now I can turn on zone 1 in living room and zone 2 cannot be found. I can put the old thermostat on and zone 2 works fine but zone one is not available. I’m needing help. I also need to know what the dip switches are supposed to be set at at each zone. We moved them to logical settings but still not working.

**chuckster57** · 08-15-2023, 06:46 PM

Welcome to the forum

What brand of AC and thermostat? I’m thinking Dometic, and if so which model of thermostat?

ChuckS · 08-15-2023, 06:51 PM

To help you we need to know:
Zone 1 AC .. what model is it
Zone 2 AC.. what model is it

Thermostat … same info

Based on my background with Alpine fifth wheels you most likely have
Zone 1 LR AC is Brisk Air II with CCC2 control board
Zone 2 BR AC is Penguin II with CCC2 control,board
Thermostat is Dometic CCC2 multizone

Picture highlights in Red zone 1 and zone 2 correct dip switch settings

** Important .. when you change dip switch settings on either AC control board you MUST do a CCC2 RESET. this allows the thermostat to talk across the CANBUS line and learn what is at each zone

Failure to do the CCC2 reset will result in frustration on your end because things will not ever work

ChuckS · 08-15-2023, 06:54 PM

This PDF contains info that should help you understand how those two roof AC units talk back and forth to the CCC2 thermostat

Also.. your furnace control board gets it’s signal to turn on or off from the Zone 1 AC roof control board.

Greg Strban · 08-16-2023, 06:21 AM

Thank you all. I will have to climb back up to get make and models on units. But based on paperwork (all but acs) every appliance in here is domestic as is the thermostat which is CCC2. Give me a day or two to work on this and will get back with you and let you know. I’m also tempted to take new thermostat to another camper and see if it works properly on another one. (My parents and my brother have duel unit campers).

jancoe1 · 08-16-2023, 07:22 AM

Check the communication line (phone line) coupler RJ11 at the a/c units.. Slight corrosion can cause loss of communication at those places. Your unit will have 2 communication lines. One from wall tstat to either the front or rear unit and then one between the 2 a/c units. Make sure there is no zone switch turned on for zone 1 a/c board and then turn on zone 2 on your 2nd a/c board. Do a reset and all is well. If it fails make a test communication line and go between the 2 airs and try again. It's a phone cable with one end reversed so it's easy to make.

jancoe1 · 08-16-2023, 07:25 AM

Those wall tstats rarely fail. Most likely not the issue here. E1 is lose of comm. Only one of those rooftop a/c units is going to have 12v batt wire to it. The other uses the comm line for board power and communication. So if zone 1 works all the time the problem can be in the line between to run 2nd a/c.

ChuckS · 08-16-2023, 10:05 AM

Quote:

Originally Posted by Greg Strban

Thank you all. I will have to climb back up to get make and models on units. But based on paperwork (all but acs) every appliance in here is domestic as is the thermostat which is CCC2. Give me a day or two to work on this and will get back with you and let you know. I’m also tempted to take new thermostat to another camper and see if it works properly on another one. (My parents and my brother have duel unit campers).

** IF you take the new thermostat to another RV that used exact same thermostat (CCC2) then you MUST do a RESET on the new thermostat when you install it or it will not work right... CANBUS has to be relearned

ChuckS · 08-16-2023, 10:07 AM

Quote:

Originally Posted by jancoe1

Those wall tstats rarely fail. Most likely not the issue here. E1 is lose of comm. Only one of those rooftop a/c units is going to have 12v batt wire to it. The other uses the comm line for board power and communication. So if zone 1 works all the time the problem can be in the line between to run 2nd a/c.

Yup this is all covered in the PDF I uploaded...

Old Mustanger · 08-16-2023, 07:43 PM

How old is/are your batteries? I was having the E1 error, had mobile repair come look at everything (I can't get on the roof to do anything myself anymore), took a quick trip to test what they did, no joy until about a half hour of being connected to shore power, so i got to thinking that it took a while to charge up the batteries enough to provide enough 12V power. Problem disappeared after replacing my batteries, coincidence? Maybe, but have not had any problems since.

ChuckS · 08-17-2023, 04:56 AM

Quote:

Originally Posted by Old Mustanger

How old is/are your batteries? I was having the E1 error, had mobile repair come look at everything (I can't get on the roof to do anything myself anymore), took a quick trip to test what they did, no joy until about a half hour of being connected to shore power, so i got to thinking that it took a while to charge up the batteries enough to provide enough 12V power. Problem disappeared after replacing my batteries, coincidence? Maybe, but have not had any problems since.

The roof AC control boards Must have 12vdc to function.. the CCC2 gets its 12 vdc from Zone 1 control board.. Low DC voltage of course will cause all of this to not work correctly... the current drain from these control boards is low so your batteries must have really been shot

Greg Strban · 08-17-2023, 06:58 AM

Both units are dometic as is the thermostat. I have all dip switches off on zone 1 except for HP and Furnace. Only switch on zone 2 that is on is the zone 2 switch. The new thermostat works everything fine on zone 1 but cannot find zone 2. When I plug old thermostat in it works zone 2 fine but cannot find zone 1. And yes I do a reset every time I move dip switches or change thermostat. I did try and check voltage at thermostat but I don’t have proper attachments for that and not sure if it’s correct. It’s showing me 5 volts. Thinking it’s supposed to be 12? But I would also think the thermostat wouldn’t work at all on that low of voltage so I must be reading it wrong. And I can get both units to come on but have to switch thermostats. The one comment about low battery isn’t the problem. It’s new and checked it at 13.5 volts. Plus it’s plugged in to shore power and I have every light on inside this dungeon trying to see these tiny wires and connections. And another thing that is different than the pics or pdf that have been shared is that my control boards have 10 dip switches and not five. I’m still trying to set them according to 5 switch set up. But zone one (if that is the big unit in living room) cannot be all dip switches off. The HP and Furnace must be on or they will not register on thermostat.

Old Mustanger · 08-17-2023, 07:37 PM

Quote:

Originally Posted by ChuckS

The roof AC control boards Must have 12vdc to function.. the CCC2 gets its 12 vdc from Zone 1 control board.. Low DC voltage of course will cause all of this to not work correctly... the current drain from these control boards is low so your batteries must have really been shot

yea they definitely were, funniest thing was the mobile guy tried to tell me that the control board wasn't communicating because I wasn't connected to a 50 AMP service.

Told him to leave.

ChuckS · 08-18-2023, 05:31 AM

On the telephone cable coming to the back of the CCC2 the Red/Black wires are
.. 12 vdc plus and ground

The Green/Yellow wires are the CANBUS wires .. the voltage will read 5 vdc when high and <5 vdc when low

ChuckS · 08-18-2023, 05:41 AM

I would also ask what the dip switch settings were on Zone 1 Before you started working on the system ..

Image of your PN CCC2 control board

ChuckS · 08-18-2023, 05:46 AM

And when you perform the RESET on the CCC2 the two zones the CCC2 finds should show up right there as zone 1 and Zone 2..

If not then with Zone 2 telephone line removed up on the roof at Zone 1 control board (for troubleshooting purposes) now doa RESET on the CCC2 and it should find and show only Zone 1

And the Modes on zone 1 should all work (Fan,Cool,FURN, etc)

If not the the control board on Zone 1 is bad

**chuckster57** · 08-18-2023, 06:27 AM

Have you tested the telephone cables?

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