Lost Zone 3

[Dbircky]

Have a Duo Therm thermostat.   After doing a reset on it, I lost Zone 3.   The 3 no longer appears on the thermostat and neither the A/C or Aqua Hot will come on on that Zone.    Zones 1 & 2 still work as before.   Nothing else has been changed.   Pulled fuse for thermostat and left it out for 20 minutes, Zone 3 still not appearing.   Cut all power to coach, still no Zone 3.  Zones 1 & 2 still work as before.  Pulled thermostat from wall and disconnected/reconnected comms cable.  Did the same at each A/C unit.   Zones 1 & 2 still work, Zone 3 still not appearing.
Any ideas of what I missed?  

[Frank McElroy]

The problem is likely the data cable connections or the data cable itself between the zone 2 and zone 3 control boards.  If you have 3 rooftop AC units the connections are under the roof AC shrouds.  If you only have 2 rooftop AC units then you have a hidden zone 3 controller.

[Chuck B 2004 Windsor]

Try finding the zone 3 controller behind the bedroom TV or in a space above the corner W/D.

[vito.a]

Do you have two Dometic 5 button thermostats?

One in front for the front A/C and another in the rear for the middle and rear A/C.  

So I assume you have three A/C's?

Why did you reset it in the first place?

Disconnecting power does not affect the thermostats.  

To perform a reset, first turn the black slide switch on the bottom off.  Then depress the top and bottom buttons simultaneously while sliding the black slide switch on. Hold the buttons down until you see FF in the display.  

If this doesn't help, then get some quality electronic contact cleaner like Hosa DeoxIT.  Diconnect each phone cable and clean the connectors.  Like the person above said drop the inside air filters down and find the phone cord junction connectors and clean each one.  Do all three A/C's as they sometimes daisy chain them.  When finished,  perform another reset.

If this doesn't fix it then get back to us as you'll have to reset the dip switches on each A/C control board. This involves removing the plastic shrouds on the roof and then the small metal cover over the control board and re-setting the dip switches.  

Also remember after resetting the thermostats or cycling power it takes 5 min for the A/C to time in. 

Best of luck.

 

Edited May 2, 2022 by vito.a

[Dbircky]

I did the reset due to Zone 3 modes blanking out after setting them AND setting Zone 1 and/or 2.    If I set Zone 1 or 2 first, the Zone 3 modes would blank.   At all times, however, Zone 3 still showed at the bottom of the screen and I could change and mode in that Zone, just not see it on the screen.  In other words Zone 3 still functioned, there was just not a way to see which mode it was in.   
 

I only have one thermostat, 3 A/Cs and Aqua Hot heating.   Zones 1 and 2 are working on all modes.   Have pulled each communication cable off and cleaned the connector including the one that plugs into the thermostat.  
 
I am not clear on why resetting the dip switches would help as none of the controlled units were changed nor was the thermostat.  Is it possible that a single zone can just die within the thermostat itself?

[Frank McElroy]

I would check the dip switch settings to be sure they are set properly.  A small amount of corrosion could cause zone 3 not to read properly or like I said before you have a bad data cable.  See page 17 in the attached file for proper dip switch settings.

 

[96 EVO]

5 hours ago, Dbircky said:

 
 

I only have one thermostat, 3 A/Cs and Aqua Hot heating.   Zones 1 and 2 are working on all modes.   

So, if your '08 is the same as mine, zone 2 should only have fan, cool, heat pump. Correct?

[Tom Cherry]

Wading in here late.  I have a 09 Camelot.  The problem, as Frank McElroy stated is that you have, most likely, lost the multiplex data loop.  Your system is programmed as follows.  When I say programmed, there is a module accessible from the top.  It has a row of dip switches. There is a layout of the dip switch settings Below.  I had to reprogram mine and learned a little.  You have the CCC one.

the Front one should only, memory, have the FURNACE in the ON position.  By default, since it is up front and has no ZONE 1, it will be read as Zone 1.

The middle one should be set as Zone 2.  The Furnace is OFF.  Your AquaHot only has 2 ZONES….so when this one Is used, it will NOT display a FURNACE on the TSAT 

Zone 3 is the rear one.  It must have the Furnace ON as it will control the rear AquaHot unit.

Monaco actually on the 40 (mine with 2 units) either goofed, or they just did is stupidly.  My system did NOT show a Zone 2….as I had no middle unit.  I reprogrammed the rear unit from Zone 3 to Zone 2 and fixed that.  

I would tell you NOT to touch the other switches.  They should all be the same.  Problem is. I can’t recall if the other switches were used….but whatever, all the other switches should be the same.

I have attached the “universal” installation PHOTO of the switches. See page 12 where the photo came from.  It explains it.  You have the dip switch module on the LEFT SIDE…or CCC

OK…..your issue, I suspect, is POOR connection.  You can “see” Zone 1 & 2, but lost or had issues with Zone 3.  The resetting of the TStat reads and records all the control modules.  You have lost Zone 3.  As suggested, unplugging and cleaning and then replugging and maybe doing that several times is the fix.  
this is how it works, the data line come in and there is a dual inline female to female connector….inside, under the cover…the control module is in the outside and is NOT polarized, the signal can come in ONE line and goes out the other.  That is for simplicity.  So, the TSTAT data line runs from the TSTAT to the front unit….and up to the control module…..then it comes back down the other phone line and connects to the line going back to Unit 2….and it repeats.  I’m drawing a blank on how the rear wall remote sensor is plugged in…..but don’t overthink this.

In order of MOST Probable causes…

Bad Connection due to wear in the connectors or some corrosion or dirt. Clean. Reseat several times.  OR Replace. I carry spares.  The issue is either on OUTGOING Line from Zone 2 or the incoming on Zone 3.  If the TSTAT never “see” or connects Zone 3, you have issues.  I would start at the middle one and clean BOTH connectors and seat, reseat, etc.  THEN, do your reset.  That clears the signal and then the TSAT will reread all the downstream items.  Sort of like rebooting your PC.

NOW, it that does not work, pull off the Zone 3 and do the same.  Again, you will have to RESET it… 

If that doesn’t work, then there are three possibilities….

1. The data line between zone 2 and zone 3 is bad…..as in Monaco nicked it during assembly and it has a cut or maybe shorted wire.  You can use a phone cable and bypass it.  This HAS happened.

2. The ends of the module connectors have been damaged or they don’t make contact.  Folks have bought the telephone connector kits and replaced the end and solved a variety of problems.

3.  LEAST LIKELY, your Zone 3 module is bad…..very rare.  These are robust, but it has happened. NUMBER ONE….loose connection.  I have had that twice and as a moderator, solved at least 20 folks problems by getting them to clean, clean, reseat, reseat…..

OK…..FINAL TIP.  Your TSat can be cleaned….but that is rarely the issue.  BUT, it has a weakness….the bottom ON/OFF switch. A wise member suggested that you ONLY use the slide switch for resetting.  You use the MODE switch to go to OFF, on each zone.  That is what I do now.

Good Luck…..this is probably simple.  As the others posted, there is a memory circuit in the system.  Even with NO DC, assuming it is only off for a few days, the TSTAT “remembers”….I think there are capacitors that stay charged….so turning on and off the power or such really doesn’t do anything.  BUT, disconnecting a phone cable kills the data loop and you have to reset the TSTAT data loop and it has to talk and do the handshake with all 3 modules.  You do NOT, I think, have a fourth or hidden module.  By  having either Zone 2 or Zone 3 (not both) have the Furnace dip switch ON, that controls the AH and you will see “furnace” on whichever zone has the Furnace ON…

let us know…..3312500_55901.pdf

//www.monacoers.org/applications/core/interface/file/attachment.php?id=10082&key=06b43f4dd053e7dea2afc07eacd2d68d

 

[Dbircky]

16 hours ago, 96 EVO said:

So, if your '08 is the same as mine, zone 2 should only have fan, cool, heat pump. Correct?

Both 1 & 2 have:

OFF

FAN ONLY

COOL

HEAT PUMP

FURNACE

Before the reset Zone 3 had exactly the same in the same order.   I just tried another identical thermostat, an Zone 3 still fails to appear.   So at least I can rule that out.    Time to start chasing the wires between 3 and the thermostat.   

[96 EVO]

So, when you turn zone 2 to furnace (with AH up to temp), which heat exchangers start up?

[Frank McElroy]

Typically the thermostat data wiring goes from the thermostat to one of the AC units (typically the one up front) then from the first AV unit to the second and then second AC unit to the third rooftop AC unit.  Take a look at the dip switch settings on each AC unit and you will find the 2nd and 3rd AC units.

[Ivan K]

I would use your extra thermostat to see if the zone shows up when connected directly to that units cable.

[Tom Cherry]

This is getting overly complicated.  
 

I did the “plug in the thermostat” in the rear.  It did not correct it when I lost the rear AC (which I reconfigured as Zone 2).  Clean the male and female connections with a Q-tip and alcohol or electronic (not ELECTRICAL) cleaner and then seat and unplug and reseat a few times to burnish and get a good connection.  That should do it.  90+% of the time, this fixes the lost or erratic zone problem.  KISS!

Other observation.  The middle AC’s control module (accessible from outside with cover off) APPEARS to be configured incorrectly.  The rear system or zone 3 should be the one controlling the AH system.  There is only TWO zones in the Camelots.  The middle unit is the smaller AC/HP.  I would turn OFF the Furnace DIP switch on zone 2.  I’ll wager at least a fifth of CR Black that.  I UNDERSTAND the adage, if it AIN’T BROKE…but in this case, someone BROKE IT…in that there are only TWO pumps or zones for the baseboard AH system.  The hallway and the bathroom and the bedroom are on ONE Pump.  If some unknowing person, or even a wrong setup originally was made, it should be corrected….

https://www.irv2.com/forums/f54/aquahot-zone-2-not-working-2008-monaco-camelot-42pdq-386568.html

If you read the above, if verifies what I said or know.  Your Zone 2 is incorrect.  NOW, will that resolve the issue?  Probably NOT, but having TWO zones control a single zone is illogical and the Thermostat may be getting confused.  I discussed this with Dometic and they said this was the way it was to be.

Work on the communications link and properly configure zone 2 and you will most likely be back in business…

Good Luck

[96 EVO]

Ha!

Vaguely recall that discussion 🙂! 

[Frank McElroy]

8 hours ago, Dbircky said:

Both 1 & 2 have:

OFF

FAN ONLY

COOL

HEAT PUMP

FURNACE

Before the reset Zone 3 had exactly the same in the same order.   I just tried another identical thermostat, an Zone 3 still fails to appear.   So at least I can rule that out.    Time to start chasing the wires between 3 and the thermostat.   

To really solve your problem, you will need to pull off the outside AC covers and look at your dip switch settings to be sure that they are set correctly.  I would move them just to be sure there is good contact  Since you have 3 AC units, the front AC unit should have no zone selected and the furnace selected.  The center AC should have both zone 2 and furnace selected.  The rear AC unit should have both zone 3 and the furnace selected.

If after you reboot the thermostat and you still don't see zone 3 then you have a data cable issue between the zone 2 and zone 3 AC units.  To verify, run an external data cable (not a telephone cable), reboot the thermostat and see if this solves the problem.

Tom, according to the 2009 Camelot wiring diagram, your coach with 2 AC units should have 3 zones.  Assuming that Monaco built your coach according to the wiring diagram, your issue is that the AC units must all be on the first available zones before setting a zone for heat only.  In your case, this means that the 2 AC units need to be on Zones 1 and 2 and the bath heat only zone set to zone 3 on the hidden controller.  See page 22 in the Camelot 2009 wiring diagram.  (NOTE - This schematic is incorrect because if shows the bath heat on zone 2 - on a 2 AC coach, zone 1 is the front AC unit, zone 2 is the rear AC unit, and zone 3 is for the bath aquahot heat only.  The 5 button thermostat must have all the AC units on the first available zones before adding heat only zones.)

 

[96 EVO]

Frank, page 19 shows the A/C wiring for coaches with 3 A/C's.

Only the front and rear show wiring to furnace. 

[Frank McElroy]

6 hours ago, 96 EVO said:

Frank, page 19 shows the A/C wiring for coaches with 3 A/C's.

Only the front and rear show wiring to furnace. 

Ben, glad you found that page.  So that means AC unit #2 would be programmed as zone 2 no furnace.  It will be interesting if there still is a hidden controller for the bath heat only as shown on page 22.  If that's the case then it would be programmed as zone 4 heat only.  That's how it is on my Dynasty with 3 AC units and 4 zones.

[Tom Cherry]

17 hours ago, Dbircky said:

Both 1 & 2 have:

OFF

FAN ONLY

COOL

HEAT PUMP

FURNACE

Before the reset Zone 3 had exactly the same in the same order.   I just tried another identical thermostat, an Zone 3 still fails to appear.   So at least I can rule that out.    Time to start chasing the wires between 3 and the thermostat.   

OK....Frank is correct about what the print says.  They prints that he has were mine originally which was a freebie set to prints from Monaco Tech Support.

As USUAL....The print is a bit confusing.  The Camelots only had ONE Comfort Control or TSAT.  There is a note on the print that confirms that. The Camelots have Remote Sensors, Hard WIRED into the controller.  My Rear AC has an unused (other side of the controller) phone (male) that goes NO WHERE.  If it had been a Contessa, it would have went to the Rear TStat...

The next thing is where it gets TRICKY.  If you follow the print, then the AH unit says there are FIVE Heating zones.  However, Zone 3 is NOT wired in.  So that makes four.  

On my system, all the AH fans or units work. BUT, I only have ONE BEDROOM blower or heat exchanger. That is the "Front" One.  I do NOT have the Rear Bedroom.  I have one in the bathroom that is switch controlled. 

Bottom Line....

FIRST, get the system functional.  You have, I believe a data connection issue.  Once you get it working, then run through the EXISTING AH Furnace program. Put ALL THREE zones in FURNACE.  Then set Zone 1 to a high temp (with the Diesel burner ON) and see what works.  Follow the prints.  Your front ones should work.  Turn down Zone 1, and then turn UP Zone 2.  See is the Bathroom works (switch is HIGH position).  Then turn down and repeat for Zone 3.....If they all work, then LEAVE the set up alone.  

From all the reading I did and my own experience, the Monaco assemblers did not always follow the prints.  SOME of the 3 AC 42 Camelots/Scepters had the Bathroom and the Bedroom TIED TOGETHER at the AH unit....like mine.  So Zone 2 really did NOT have a FURNACE setting....and they did not "see that" on the TStat. BUT, since yours DOES, then you are closer to the PRINT....and it MIGHT NOT BE BROKE.

The Joys of Monaco folks wiring stuff like they should.

FIX the Data Link and you should be good to go.

 

[hitechpete]

If you plug your spare CCC  into the cable going from the middle A/C to the 3rd A/C and perform a reset it should find the missing zone. If it does not find the zone, either the phone cable is faulty or the module in the A/C is faulty. If you plug a spare phone cable (4 wire) into the 3rd A/C unit and perform the reset again it should either: work and prove the existing link cable is faulty or not work and prove the A/C control module is at fault. My Penguin 2s had water in the tub that the connectors were laid in.

[96 EVO]

5 hours ago, Frank McElroy said:

Ben, glad you found that page.  So that means AC unit #2 would be programmed as zone 2 no furnace.  It will be interesting if there still is a hidden controller for the bath heat only as shown on page 22.  If that's the case then it would be programmed as zone 4 heat only.  That's how it is on my Dynasty with 3 AC units and 4 zones.

Yeah, in the toilet room in the Camelot / Scepter is a off / low/ high switch for that heat exchanger fan, but the heat exchanger itself is in the same loop as the bedroom and shower room heat exchangers.

Zone 2 on my thermostat only controls the mid HP.

Edited May 4, 2022 by 96 EVO

[Tom Cherry]

2 hours ago, 96 EVO said:

Yeah, in the toilet room in the Camelot / Scepter is a off / low/ high switch for that heat exchanger fan, but the heat exchanger itself is in the same loop as the bedroom and shower room heat exchangers.

Zone 2 on my thermostat only controls the mid HP.

This has been the point all along.  Let’s try to define it.

Zone 1 is living.  
Zone 2 is mid or hallway IF YOU HAVE A 42 a which has 3 AC’s.

Zone 3 is rear bedroom.

Monaco had two preprogrammed or configured AC units.  Both were 15K.  One was labeled (internally) Zone 1 (front) and Zone 3 (rear).  So if you have the 40 or TWO AC units, you had Zone 1 and Zone 3.  There is NO Zone 2.  
 

Monaco THEN had, on the 40 ft TWO AC a units, to jumperor tieor used the Bedroom, hall and bathroom heat exchangers as ONE ZONE…..and it was controlled by the Bedroom Zone 3 mode.

that is the ONLY away you got rear heat.  Mine was Zone 3 and I reconfigured it to ZONE 2.  I just turned OFF Zone 3 and turned ON Zone 2.  Nothing MORE.

NOW, the print that I gave Frank and he posted show that the Bathroom heater (2 speed on and OFF switch) is SUPPOSED to be  controlled from the ZONE 2 Middle control box.  That is also what the Owner’s manual says.

BUT, there are at least 20 posts here and on IRV2 that dispute that.  Simple.  The Assembly or production folks wired the AquaHot unit like it was a 2 AC 40 foot unit. If you have one like that, then all the NON LIVING ROOM heat exchangers ALL COME ON AT ONCE….from Zone 3.  So, in essence, those 42’s have a 40 wiring configuration on the Aqua Hot.  Then, when you toggle through the modes, the Zone 2 has NO FURNACE….as the “Furnace” Dip Switch is off.

BUT, the original poster said he had Furnace on all three zones.  His is wired like the print calls for.  His bathroom heater is only supposed to operate from the Zone 2 Furnace Mode. 
 

It really doesn’t matter as long as one understands how theirs works.  BUT, you can NOT tell someone that has the 42 series but has THREE Furnace modes that that is wrong.  It was the way that Monaco wired it…..and it is a hybrid with a 3 AC configuration, but the Bathroom was added, probably stupidity or lack of standardization, by an unknowing assembly line person that THOUGHT all the AH were to be wired the same.  
 

changing the AH wiring and making it like the original design print, assuming that they put all the zones 1 & 2 FAN  on one set (Fan 1) terminals and that the Zone 2 thermostat line is correct, is an easy change.  All that  does is separate the bathroom heater….which can be turned off anyway.

The original poster’s issue is NOT whether it is to “Print” or the Hybrid….his issue is the multiplexed data loop from Zone 2 to Zone 3 has an open circuit or there is grease or grime or the plug backed out.  That has to be fixed and it is either in the outgoing Zone 2 data line or the incoming Zone 3 data line.  KISS….

Fix or repair the data loop….then Zone 3 will work.  In his case, he will (or is) be to the print…..but dropping out a zone is a common occurrence and needs to be trouble shot and fixed….

As a moderator, I am asking the original poster to follow the a above. If he doesn’t understand the multiplex data loop or can’t reestablish the data loop, then get a tech to fix it.  Comparing the same coach or it’s brother is not productive as one has to understand that there are two different AquaHot configurations.  Both work, but the modes will be different.  You have got to fix the data loop….or determine that the control module in zone 3 is defective……less than a 5% probability based on 13 years of moderating and reading the posts here and on the original site.

thanks….

 

[96 EVO]

6 hours ago, Tom Cherry said:

 

BUT, the original poster said he had Furnace on all three zones.  His is wired like the print calls for.  His bathroom heater is only supposed to operate from the Zone 2 Furnace Mode. 
 

 

 

This is what I'm curious about, and why I asked which heat exchangers run when he turns thermostat zone 2 to furnace mode.

Maybe he has a different floor plan than myself, and they added a third zone pump in his AH system.

[Tom Cherry]

10 hours ago, 96 EVO said:

This is what I'm curious about, and why I asked which heat exchangers run when he turns thermostat zone 2 to furnace mode.

Maybe he has a different floor plan than myself, and they added a third zone pump in his AH system.

Ben, your curiosity is good.  Here, I think, is the answer.

Your manual (actually the 2008 Camelot as that was easier to find) says the Furnace will ONLY operate in Zones 1 & 3.  That means that the 40 and 42 ft 2008’s had an IDENTICAL AquaHot configuration and Zone 2 was programmed or configured as a AC/HP only unit,  NOW, as to whether  your Zone 2 also has the separate thermostat output to the AquaHot, I don’t know.

The Print that Frank has, which I provided, lists the AquaHot configuration for MY 2009.  So the original poster has a different wiring configuration.  There is also a change in the Owners manual and there is a chart or table in the 2009 manual that shows the mid or Zone 2 unit controls the center section. The print was drawn in late 2007 and was “released” for the 2009 MY.

As best I can determine, the AquaHot units are the same with the capability of 5 Zones.  In your 2008 3 AC coach and my 2009 2 AC coach, we only use 3 AquaHot Zones.  In the 2009 3 AC coaches, the Bathroom heater is separate from the .bedroom heater and has its own Zone (2 on the AQUAHOT terminal strip).  That AquaHot Zone 2 is only for the Bathroom heater.  There is still a “spare” or unused zone in the AquaHot control panel.

I THINK this clears it up.  Now, were some of the later 2008’s wired to the 2009 print?  Probably, but who knows.  Now, were some of 2009’s wired to the older  2008 configuration?  Probably, but who knows.  

Bottom Line, the prints call for two separate control configurations between 2008 and 2009.  So that mystery is resolved.  Our original founder, Colonel Bill often cautioned us about assuming that two consecutively built EXACTLY the SAME, MH were, in fact, the same.  Monaco had very little standardization on the assembly floor and documentation was more OTJ Training and word of mouth. Those of us that were in Engineering Management for any major Automotive supplier or Manufacturer can attest that in the mid 80’s, there was an industry wide (US)  push to improve quality and emulate the Japanese folks that used the Deming Statistical Process Control techniques that required extensive Operator Instruction Sheets as well as having “fill in” operators being THOROUGHLY cross trained so that there was a more consistent and higher quality level in our supplier parts as well as the Car assembly plants.

THAT NEVER HAPPENED at Monaco….Winnebago was much better and had better print control. Dealers and repair shops that worked on both said that the Winnebago’s were, much closer to the prints, than Monaco.  NOW, this riddle has been solved.  
 

We need the original poster to focus on the proper trouble shooting and reestablish his data link…. His thermostats are configured to the 2009 prints.  Therefore the issue has to be the data link and/or a defective control module in the rear AC….

Thanks for posting the comment and forcing me to do some digging…..we can all rest easier now….LOL….