2009 Camelot AC issues

[CaptPat]

We took our MH to a local campground for a shakedown, as it's been awhile since we've used it, in preparation for a longer trip in September.  We experienced some unusual behavior from each of the 3 AC units, particulars follow--
 
 We have 2 Dometic 630516.331, and 1 630035.331 with a DuoTherm  5-button thermostat.
 
 We ran all AC's on the generator for the 1 hour trip to the  campground, set up and switchover to site power went uneventfully.   Later in the afternoon units 1 and 2 stopped, though the thermostat  indicated both 1 and 2 with bars under them.  I reset the thermostat  and AC 1 and 2 restarted they ran for another 2 hours before stopping  again. Repeated the process successfully, when we went to bed I turned  1 off, leaving 2 and 3 (BR) to run through the night.
 
 In the morning 3 was still running, I assumed 2 had turned off as the  set temperature was reached, thermostat showed 2 no underline, and 3  underline.  As the day heated up 2 would not start when called for by  the thermostat, neither would 1.  I tried resetting the main power,  and shifting to the generator no change.  Eventually I was able to  restart 1 and 2, they ran for about 90 minutes before shutting down  again, shortly thereafter 3 stopped, thermostat showed 3 with  underline at this time.
 
 When I reset the thermostat (several times over the day and a half and tried to start units to AC mode I  could hear what sounded like a contact picking up near the inlet  plenums though the units were not turning on. I'm pretty sure that  site power was okay as my surge protector indicated normal V/Hz/A  readings.  When running each unit seemed normal, cold air and normal  air flow.  At no time did any of the site or coach breakers trip.
 
 Does this sound like a capacitor issue or something else?  The next  several days are going to be way too hot (99+) to go on the roof to  see for myself.  Once I get up there is there anything else I should  check?

Thanks

[Dwight]

I have found the thermostats in our ‘07 Diplomat to be very inaccurate. Dometic.  I must keep lowering the temp to keep it running sometimes then it gets too cold and I must keep adjusting opposite. 

[CaptPat]

19 minutes ago, Dwight said:

I have found the thermostats in our ‘07 Diplomat to be very inaccurate. Dometic.  I must keep lowering the temp to keep it running sometimes then it gets too cold and I must keep adjusting opposite. 

I don't think it's the thermostat, temps in the coach were well above the set point and the thermostat was calling for the AC units to start.

[Dwight]

Just seems I need to constantly raise or lower the thermostat to keep the temp we want. It was very hot last week. 
 

Our previous MH was a Bounder with one thermostat located on an outer wall of the coach-same Problem 

[jacwjames]

Maybe try unplugging and plugging back in the communication cables, the connectors are located up under the AC units accessible from inside, may be tucked up high.  Also unplug and plug back in the cable on the back of the thermostat.  May have a little corrosion on the connectors.

[vito.a]

Clean the RJ11 cable connectors and junction with DeOxit. 

https://www.amazon.com/DeoxIT-D5S-6-Contact-Cleaner-Integrated/dp/B0002BBV4G/ref=sr_1_3?crid=1DWKHYTV8A0NC&keywords=deoxit&qid=1659025191&sprefix=deoxit%2Caps%2C115&sr=8-3

If that doesn't help then test capacitors.   Many folks at this point just order new units.  If you get to that point then you need to understand you cannot mix the new A/C units with the old 5 button thermostat.  There is a retrofit control board but they are not currently available.  

[TimSpencer]

You may want to check/clean condenser coil on unit. Driving down the road may have provided extra air flow to keep unit running fine. But while stationary you rely on the condenser fan in the unit and if the coil is dirty or plugged it may cause unit to trip on high pressure. If it’s cycling on temp and then not restating when temp comes back up I would check the start components like capacitor and stat. 

[Chuck B 2004 Windsor]

There should be a temperature sensor used to control the unit.  Monaco put one of ours in the air intake of the air conditioner.  It needs to be moved to where no air is blowing on it.

Chuck B.  2004 Windsor

[Tom Cherry]

4 hours ago, jacwjames said:

Maybe try unplugging and plugging back in the communication cables, the connectors are located up under the AC units accessible from inside, may be tucked up high.  Also unplug and plug back in the cable on the back of the thermostat.  May have a little corrosion on the connectors.

RIGHT.  First rule is AC funky or what is BAD CONNECTIONS in Data or control lines.   Covered in several other threads.

Drop the covers on all the AC’s.  You will see two in-line phone cable connections.  Mark the cables as A on both ends and B on the other one.  Really doesn’t matter, but put it back as before.  Use alcohol or electronic…NOT ELECTRICAL CLEANER.  Spray or use Q-tip and cleaned the male and female gold contacts.  Then plug in, unplug and then repeat and “forcefully” seat or insure the males are in the females.  Again, the cables are not polarized…..but I keep them match like before.

Next…usually NOT an issue…but do it.  Remove the Thermostat.  There is a phone connector.  Clean the Thermostat female and the male as well.

NOW…turn OFF….using the bottom switch, the Thermostat.  Remount after plugging in.  Hold the TOP and BOTTOM BUTTONS IN and then turn on power.  Let off…maybe a second after power on.  You will see FF.  This means that you have rebooted and reestablished the data link.  This IS A COMMON issue.  My guess.  Oil and condensation and also just plain vibration is giving an erratic or intermittent connection at one, or more of the in-line connectors.  Even a few degrees heat or cold difference will cause the data loop to go blank and the Thermostat will NOT control the system properly. Been there…done it twice.  I now carry new connectors.  WORST CASE…a male cable is bad and you use a phone connector kit from Lowes and reterminate.  THEN, if this doesn’t fix it, start trouble shooting capacitors and such.  NOT saying this is the issue and there are electrical gremlins and such…but you MUST have a good data or control path to isolate or resolve the real issues.

Try it and let us know.  YES…this happened to me…drove 5 hours…AC and Genny worked great.  Stopped and deployed slides and plugged in.  NO REAR AC.  Just the lack of vibration making the circuit on either the outgoing line from the front to my only other AC, in bedroom, or the incoming phone connection back there shut down.  Fumed in 100+ weather in SC and finally cleaned and reset.  Worked fine every since…but I now have (2 actuality sets of spares and I lost one and then reordered and found the second set).

Good Luck.  Let us know.

[CaptPat]

@Tom Cherry Thanks, I’ll clean the comms connections and re-try.  Where did you get the spares?

 

[Chuck B 2004 Windsor]

40 minutes ago, CaptPat said:

@Tom Cherry Thanks, I’ll clean the comms connections and re-try.  Where did you get the spares?

 

There should be a temperature sensor used to control the unit.  Monaco put one of ours in the air intake of the air conditioner.  It needs to be moved to where no air is blowing on it.

Chuck B.  2004 Windsor

Nothing is ever said about the use of the flat telephone cable.  The flat cable is subject to cross talk because there is no twist in the wires.  Cross talk can come from various sources.  The most common source is the florescent lights in the ceiling.  Also there is the use of the flat telephone cable as data cable.  The difference is how the plug is mounted on each end.  On telephone cable the clip is mounted with both clips facing in one direction.  When used as a data cable the clips are mounted one end with the clip up and the other end with the clip facing down.  When looking at the width of the cable you will notice a ridge on one side.  That ridge is there to let you know which side of the cable it is.   I replaced all my flat ribbon cable with 2 pair JKT cable.  Red, green, yellow, and black wires in the cable.  The red and green are twisted, and the yellow and black are twisted.  

Hope this helps,  Chuck B 2004 Windsor

[Tom Cherry]

2 hours ago, CaptPat said:

@Tom Cherry Thanks, I’ll clean the comms connections and re-try.  Where did you get the spares?

 

Since we don’t have Radio Shacks, you COULD try Lowes.  I just ordered them from.  The standard, I think, is the RJ 11 Female to Female.  Look them up there.  There are…memory and Chuck, an old Telephone guy can chime in, nothing but a 4 wire cable.  Having spares is always nice.

Chuck is also correct.  Theses weren’t the highest grade cables…and yes, there is a host of RFI stuff that can interfere.  BUT, the most common is a Fluorescent ballast going bad. Test the unit and turn off….all the Fluorescent lights.  NOW, on the side of each fixture is an ON/OFF a power switch.  Turn them all OFF.

The final, 100% test to really eliminate RFI from a faulty ballast….go to the bathroom.  You have 3 Intellitec boxes.  One is labeled as a Relay or Relay Output.  That, one, FYI, controls the ON/OFF functions of all 3 Fantastic Fans; the Water Pump and the Fluorescent fixture circuits.  Don’t know about your 42, but probably have one Bedroom; one private toilet, one hallway or shower area or Vanity and the Galley/Living area.  If you look at the fuses there are 10 (memory) on the that Intellitec box.  The OTHERS or other 2 boxes are for the incandescent lighting circuits and they are the “Dimming” ones.  So…pull the fuses out for the Fluorescent lights in the Relay Output module….that TOTALLY removes power…

IF issues after that, then start a deeper dive.  Fix or make sure the data line is good and that the thermostat is working and all seems normal.

BTW.  To prevent future issues, folks recommend that you do NOT turn off the Thermostat using the switch.  Use the MODE and turn off each one from there

[96 EVO]

You have the fans set to low / high/ or Auto when the unit's are completely shutting down?

 

[CaptPat]

9 hours ago, 96 EVO said:

You have the fans set to low / high/ or Auto when the unit's are completely shutting down?

 

Yes I tried all three fan speeds it didn't make a difference.  I'm going to try cleaning the comms connectors today to see if that makes a difference.

 

@Tom Cherry I always turn off the AC units at the thermostat first, then turn off the thermostat itself.  I normally turn on the thermostat using the resetting procedure and always get "FF."  Looks like F-F RJ11 connectors are readily available, amazon and elsewhere.

[Tom Cherry]

44 minutes ago, CaptPat said:

Yes I tried all three fan speeds it didn't make a difference.  I'm going to try cleaning the comms connectors today to see if that makes a difference.

 

@Tom Cherry I always turn off the AC units at the thermostat first, then turn off the thermostat itself.  I normally turn on the thermostat using the resetting procedure and always get "FF."  Looks like F-F RJ11 connectors are readily available, amazon and elsewhere.

My advice...FWIW.  I would only use the "Mode" control. I "Save" my snap switch for only doing resets or if there are issues. Most of the older and probably some recent members have reported that the snap or mechanical switch is a high frequency failure item. The electronic "Mode" off, they, and I also, feel is less likely to fail. I have taken apart my T'Stat and done the "Erasure and Acetone (alcohol?) cleaning of the pads and contacts.......  Much like you have to do to salvage a grumpy car remote fob.

You MAY have issues...but if there are incremental environmental conditions....such as temperature and vibration....then there is (may?) be a high probability that the Thermostat is "losing the circuit". Folks have fussed and fumed for at least 13 years, my tenure, and the most reliable "fix" has been to do PN on the phone lines.  Past that, it gets more technical....

Good Luck....Let us know....  Being a 2 time VICTIM of "Gotta HAVE AC" and the eventual fix....cleaning and restoring the Data line was the fix.  Along the way, I DID learn a lot and how the systems work and how the com line and the DIP setting are to be programmed.  

 

[CaptPat]

I cleaned all of the RJ11 connectors there are XX of them.  Two female to female in the front AC, two comms line in the mid -- they plug directly into the control box, 1 female to female in the rear and the connector on the back of the thermostat itself.  All three ACs have been running fine on the generator for ~45 minutes.  I did monkey around with the fluorescent lights throughout the MH and could not induce an issue.

Visually the connectors seemed fine and only a very small amount of discoloration was observed on the cotton swabs soaked in 91% isopropyl alcohol.  We're expecting the temps to come down below 90* in the next couple days, then I'll check out under the covers on the roof to make sure everything looks okay. 

At this point I'm cautiously optimistic that the issue has been corrected, I've seen these things operate for awhile and then refuse to cooperate all of a sudden.

@Chuck B 2004 Windsor I'd be interested in hearing more about how you replaced the telephone flat cable with JKT, in particular how you terminated them and any issues fishing them through the ceiling. 

[jacwjames]

Hopefully you got it fixed.

One issue, at least for me, concerning the communication cables is that they are routed in the wall and then the ceiling from the thermostat to the rear AC unit and then from the rear AC to the front AC.  Not an easy way to replace them.  From the rear AC to the front AC you could cut holes in the duct work and pull them through, but from the rear AC to thermostat not sure what you could do.

[CaptPat]

Well looks like I spoke too soon, at the 50 minute mark all three AC units shut down, thermostat showed 1, 2, and 3 all with an underline.  Resetting the thermostat did not resolve the issue, fluorescent lights were off the fuses were still installed.  Bad theremostat?

[96 EVO]

51 minutes ago, CaptPat said:

Well looks like I spoke too soon, at the 50 minute mark all three AC units shut down, thermostat showed 1, 2, and 3 all with an underline.  Resetting the thermostat did not resolve the issue, fluorescent lights were off the fuses were still installed.  Bad theremostat?

Possibly.

There's no way you have bad capacitors in all 3 units!

[Chuck B 2004 Windsor]

1 hour ago, CaptPat said:

I cleaned all of the RJ11 connectors there are XX of them.  Two female to female in the front AC, two comms line in the mid -- they plug directly into the control box, 1 female to female in the rear and the connector on the back of the thermostat itself.  All three ACs have been running fine on the generator for ~45 minutes.  I did monkey around with the fluorescent lights throughout the MH and could not induce an issue.

Visually the connectors seemed fine and only a very small amount of discoloration was observed on the cotton swabs soaked in 91% isopropyl alcohol.  We're expecting the temps to come down below 90* in the next couple days, then I'll check out under the covers on the roof to make sure everything looks okay. 

At this point I'm cautiously optimistic that the issue has been corrected, I've seen these things operate for awhile and then refuse to cooperate all of a sudden.

@Chuck B 2004 Windsor I'd be interested in hearing more about how you replaced the telephone flat cable with JKT, in particular how you terminated them and any issues fishing them through the ceiling. 

You can use a conduit fish tape to fish the JKT through the ceiling the entire length of the coach.  Just run the fish tape as far as you can to the next ceiling access be it lights, etc.  You can use a standard phone connecting block to plug the cable into to gain access to each wire.  

Chuck B 2004 Windsor

https://www.lowes.com/search?searchTerm=telephone splice connectors

[Tom Cherry]

1 hour ago, CaptPat said:

Well looks like I spoke too soon, at the 50 minute mark all three AC units shut down, thermostat showed 1, 2, and 3 all with an underline.  Resetting the thermostat did not resolve the issue, fluorescent lights were off the fuses were still installed.  Bad theremostat?

BUMMER....and, even with quite a bit of "googling", no JOY on any OTHER site.  WITH the risk of shotgunning.... there would be only ONE more test or step...which is easy, relatively speaking.  RESET your Intellitec EMS. IF there is an issue, then maybe the load shedding is crazy. NO IDEA or even brain storm as to WHY the TStat has the strange display. Turn off all the POWER (incoming).  Pull the 4 or so screws from the main breaker cover and pull it. On the RIGHT (memory) side, there is a "module".  There is a 3 or 5 amp mini fuse there. There are one or two pigtails. I always remove the fuse and the pigtails and then wait a few minutes. Replace the pigtails and then the fuse. You have RESET IT. Then turn on the AC's and run and wait...

NO GUARANTEES....or whatever. I ASSUME that you have cleaned the contacts on the phone connection to the TStat. I did spray some electronic contact cleaner inside the snap switch.  You can try googling. You can TRY Lippert which has a Tech Support line and see if there are any geriatric folks that have had the "3 UNDERLINED" screens.

There are, I THINK....search here, there is a a NEW "Clone" Thermostat folks are using that will interface with the older, out of production, 5 button DuoTherm TStat.  You MIGHT call them and ask them....  Otherwise, you do some ebay looking and searching. There are several (used to be) folks that will repair and test and swap for a "Refurbished" TStat. Some folks carry a spare. 

From a 30K Observation...I can NOT come up with ANY good reason...why all three units would shut down....and give you the ODD display....BUT....if you had an "intermittent" load shed, which has happened....then all three units would drop power...maybe for a nano or mili second...and then be restored.

OK....ONE LAST or the NEXT STEP....and I did some consulting....with our "Mr. Wizard".  The above MAY work.  but, if there is a problem in the PCB on the EMS and you are getting ALL voltage dropped out...chasing a bad thermostat is a waste....so....follow along.

First...  Our Intellitec Tech Support resource, M&M RV Electronics (the are PAID to provide) says that even turning OFF the individual side or ON/OFF switches does not isolate or remove a bad Ballast.  The ONLY WAY...pull the FUSES.  FWIW....that is THEIR first STEP in eliminating RFI or interference...

BTW....When this HAPPENS...how long do you have to wait to get the systems operational AGAIN?  THAT might be the CLUE and WE think you MAY have a Power issue...as in LOAD shedding....  Or did someone turn on a hopped up radio or drone transmitter and put out some really spooky EMP/EMF/RFI.  Seriously, some folks have turned on devices and the wireless or the remote control or connection has actually impacted the TStats...back to Chuck's theory...

BUT....here is the next step. Let it "Cool OFF" so that you can restart the system....AFTER you do the EMS reset.  IF it persists....then here is your only other, plausible option....and it is important, we think for you and OTHERS to know about the Intellitec EMS SYstem.

I can NOT remember nor does my Manual say EXACTLY what circuits are on the Load Shed. The Front and Rear AC are on the print....and I only have them. IF your EMS has them lighted....I THOUGHT there was a name or indicator. IF ALL THREE AC's are on the SHED LIST>>>>> Then that is the next step.  The EMS has RELAYS FOR ALL THREE...

NOW...if you have the prints or look at the unit, Monaco GOOFED....and YES, this is documented, sometimes overlooked....but it was a Mistake and INTELLITEC told them and they chose NOT to follow the installation.  There are THREE relays and a Terminal Strip that has 6 connections for the THREE AC's.  The relays on the Intellitec Board were not "rated" for the constant ON/OFF or direct AC current. Monaco SHOULD have run each Thermostat or 12 VDC Control Voltage....through the Intellitec. That would have meant that when the DC power was run to the AC unit....alongside the AC, that it SHOULD have been THROUGH the Terminal Strip....on the drawing it SHOWS that.  GUESS WHAT?  Monaco ran the 15 A AC there directly...never meant to SWITCH AC.  WHAT A FIASCO. I knew about this...and Dr. Wiz reminded me and we looked it up.

SO...If the PCB in the EMS has a break or a bad circuit....there COULD be a Momentary....almost imperceptable DROP OUT.  That killed the AC's and there was, even though the Thermstat is DC, sent back a feed back.  NOW....the ONLY way to verify that is NOT happening.....HANG ON...

With the Panel off and the POWER OFF. You need to use an OHM (Continuity) meter.  On the OUTPUT side of Front AC, probe that and find the INCOMING line on the EMS.  Probably one ONE of the terminal Strips. THEN the other side has to be the OUTPUT side...as in the BLACK.  If you get the system BACK UP....then, do a little leg work...  Turn OFF the Rear and Middle AC Breaker. Then, probe the Terminal Strip. You should (measuring 120 VAC to GROUND....and you can use the Equipment Ground or take a 3 pronged plug and attach a lead to the GROUND in an outlet).  Measure the voltage and find the TWO terminals that have 120 on that AC 6 terminal strip.  SEE the PRINT ATTACHED.  Probably should be 1 & 2 or 3 & 4 or 5 & 6.  Once you isolate WHICH wires have 120 VAC.  THEN use the Ohm meter and find which is the INCOMING.  Then repeat.  You have MARKED the THREE incoming legs for each AC. I THINK the easiest would be to use a Red Wire Nut and then connect the In and OUT for Front AC....and bypass the RELAY.  DO the same for the OTHERS.  NOW test.  IF they run great...you need to contact M&M and get a replacement for the the EMS.  IF they still fail on or about the SAME time....then there is PROBABLY a Thermostat issue....

Hope this helps....a little long, but this ain't exactly a "hook up them jumper cables" deal.

Good Luck...Let us know...

12 V Energy Management.pdf

[CaptPat]

Since all 3 AC are affected at about the same time it's unlikely a capacitor issue, and when running the units are blowing and cooling just fine.  I think the thermostat is working fine.  That leaves the EMS or the Transfer switch as possible sources (recall the situation is the same on GEN or site power).  I don't think EMI from the neighbors is at fault, at home there's no one close, plus the issue was observed on the road and at a campground.  Fluorescent light ballast interference is still a possibility though it's not high on my list at this time.

I did poke around in the EMS box a bit and it appears to be wired as shown in the diagram above. Wires from the 120V terminal block to the breakers is a bit of a birds nest but should be traceable. I was able to get some movement on a couple terminal connections but not enough to be of concern and I wiggled most of the connections.  I did not find any glaring issues the fuse was fine and the green comms light was lit.  I restarted the generator and the relays clicked on when the generator started putting out voltage.  AC units restarted -- no problems.  I was hoping to observe a load shed event but after 1.5 hrs of uneventful run time and no shutdowns I gave up and shut everything down. 

I'll study your T/S suggestions of the EMS and try to get to that tomorrow.  I'll also check on the roof units to eliminate any issues that might be occurring up there as well.

The transfer switch is not the original IOTA and it seems to be pretty robust, a visual inspection revealed no issues, all connectors were tight.  A momentary issue here may cause an interruption in power as well.  Don't know how to test it however.

WRT a new thermostat I think I'll go with Micro-Air, they apparently have a model that is a plug and play replacement for the 5 button.  Plus it has some programming capabilities and BT connectivity.  Seems to be a better alternative than trying to find an extinct 5 button in good working order.

Edited July 29, 2022 by CaptPat
correction

[96 EVO]

Any issues with any other appliances in the coach when the A/C's shut down?

Microwave clock need reset? This won't happen if you have the inverter turned on.

[jacwjames]

Do all 3 of your AC pass through the EMS?  When my EMS failed I bypassed one AC to get by until I could replace the EMS.  You could consider bypassing the EMS to completely rule this out as a problem. 

When I replaced my AC's last year I did install the Micro-Air Easy Touch, since I was going to have to replace my 5 button anyway it wasn't that much more money.  It was plug and play.  I use my phone to control the AC's via blue tooth but it will also connect via WIFI.  Both are great features.  When I was camping in colder weather I'd use the phone to turn the furnace on to warm up the coach in the AM, I don't mind sleeping in a cold bedroom but hate getting up in one.  While I was in TX I was ~30 miles from the coach and checked the temps and it had climbed to almost 90F, so I turned on one AC and by the time I returned it had lowered to 78F. 

Another advantage is that you can set up the Mirco-Air to send you alerts for temps, so if you have dogs it's a great feature. 

[Tom Cherry]

8 minutes ago, CaptPat said:

Since all 3 AC are affected at about the same time it's unlikely a capacitor issue, and when running the units are blowing and cooling just fine.  I think the thermostat is working fine.  That leaves the EMS or the Transfer switch as possible sources (recall the situation is the same on GEN or site power).  I don't think EMI from the neighbors is at fault, at home there's no one close, plus the issue was observed on the road and at a campground.  Fluorescent light ballast interference is still a possibility though it's not high on my list at this time.

I did poke around in the EMS box a bit and it appears to be wired as shown in the diagram above. Wires from the 120V terminal block to the breakers is a bit of a birds nest but should be traceable. I was able to get some movement on a couple terminal connections but not enough to be of concern and I wiggled most of the connections.  I did not find any glaring issues the fuse was fine and the green comms light was lit.  I restarted the generator and the relays clicked on when the generator started putting out voltage.  AC units restarted -- no problems.  I was hoping to observe a load shed event but after 1.5 hrs of uneventful run time and no shutdowns I gave up and shut everything down. 

I'll study your T/S suggestions of the EMS and try to get to that tomorrow.  I'll also check on the roof units to eliminate any issues that might be occurring up there as well.

The transfer switch is not the original IOTA and it seems to be pretty robust, a visual inspection revealed no issues, all connectors were tight.  A momentary issue here may cause an interruption in power as well.  Don't know how to test it however.

WRT a new thermostat I think I'll go with Micro-Air, they apparently have a model that is a plug and play replacement for the 5 button.  Plus it has some programming capabilities and BT connectivity.  Seems to be a better alternative than trying to find an extinct 5 button in good working order.

Cool….folks like you that jump on things and study and provide prompt feedback makes it easier for the group to help.  Totally agree.  If this were common on MH that did not have a miss wired EMS, THEN here or on the various other locations would have had a “Gee….what is this?” topic.  
 

FWIW…The odds, but never know, of some crazy RFI are slim, but just repositioning a Garmin GPS was enough to disrupt the “electronic” cloud in my Camelot and the RR PressurePro sensors stopped working after 6 months.  Probably batteries were at 90% and not fresh out of box.  But. I did have “noise” and playing around with the GPS MOVED the bars or the measurements on the receiver….so, a bathroom repeater, have I.

Bottom line…reset the EMS.  Test again.  Still NO JOY….3 wire nuts and bypassing or removing the shedding relays will tell the tale.

I spent months chasing a “ghost” activated Intellitec under counter light in the private bath.  It would come on intermittently or sometimes go for a month OK.  I tried every trick M&M suggested, save a upgrade of the entire EMS, which IS connected to the Multiplex system…remotely, but in the architecture.  Finally, got a late member and Mr, Wiz to start experimenting and we changed codes and routed the “ON” Command to another module and circuit.  Stayed with the switch.  Got a replacement programmed and modified, that switch IS unique as it has contacts not in the Multiplex wiring.  Swapped…no issues in 4 years.  Told M&M.  OK…Tactile (intermittent momentary touch” issue….rare, very rare….but happens.

I don’t know if a bad EMS board, but it is moving right up the list of the “usual” suspects….

Keep trouble shooting and posting…we all learn

5 minutes ago, jacwjames said:

Do all 3 of your AC pass through the EMS?  When my EMS failed I bypassed one AC to get by until I could replace the EMS.  You could consider bypassing the EMS to completely rule this out as a problem. 

When I replaced my AC's last year I did install the Micro-Air Easy Touch, since I was going to have to replace my 5 button anyway it wasn't that much more money.  It was plug and play.  I use my phone to control the AC's via blue tooth but it will also connect via WIFI.  Both are great features.  When I was camping in colder weather I'd use the phone to turn the furnace on to warm up the coach in the AM, I don't mind sleeping in a cold bedroom but hate getting up in one.  While I was in TX I was ~30 miles from the coach and checked the temps and it had climbed to almost 90F, so I turned on one AC and by the time I returned it had lowered to 78F. 

Another advantage is that you can set up the Mirco-Air to send you alerts for temps, so if you have dogs it's a great feature. 

Me thinks YES….based on the print and past posters.  It is designed for a 3 AC system.  Just wire nutting the in and out for each AC will be simple…once you do a quick continuity and voltage  test….and no wiring mods and easy to restore.

I don’t see any other suspicious “perps”….even in the whole camp ground….  Fun and games….where you learn and save needless costs and times…

Good info on the replacement…..if needed.  It MIGHT not be susceptible…thanks.