Dometic Blizzard NXT w/CCC2

[Gerry f]

I have a 2007 Executive Sandia IV

I replaced all three of the Penguin roof A/C Heat pump units with Blizzard NXT's  I also replaced the old thermostat with CCC2.  Everything seemed to work okay until I tried to use the furnace in zones 2 and 3.  Zone 1 in the front and kitchen works great.  They would not come on.  I read that there is a fourth Dometic controller (Brain) that also must be replace to get AquaHot to work properly.  I have been unable to locate this magic fourth controller (Brain).  Does anyone know where Monaco might have hid this unit.  I looked behind the cabinet that is behind the thermostat that is on the back side of the shower and it was not there.

Any help that can be provided would be appreciated.

Thanks,

Gerry Faulkner

2007 Executive Sandia IV 600hp Cummins

[vito.a]

Did you have 4 zones on your previous thermostat?  

If so, look at this thread (but it's for a 2008 model):  

If not, then you probably have the dip switches incorrectly set on your zones 2 and 3 A/C control boards. 

Did you copy the settings exactly from the previous Penguin units?

 

Edited May 1, 2023 by vito.a

[Tom Cherry]

18 hours ago, Gerry f said:

I have a 2007 Executive Sandia IV

I replaced all three of the Penguin roof A/C Heat pump units with Blizzard NXT's  I also replaced the old thermostat with CCC2.  Everything seemed to work okay until I tried to use the furnace in zones 2 and 3.  Zone 1 in the front and kitchen works great.  They would not come on.  I read that there is a fourth Dometic controller (Brain) that also must be replace to get AquaHot to work properly.  I have been unable to locate this magic fourth controller (Brain).  Does anyone know where Monaco might have hid this unit.  I looked behind the cabinet that is behind the thermostat that is on the back side of the shower and it was not there.

Any help that can be provided would be appreciated.

Thanks,

Gerry Faulkner

2007 Executive Sandia IV 600hp Cummins

@Gerry f

OK....from the TOP.  First I did NOT fully understand how the Blizzard NXT's work...as in their CONTROL MODULES...  BUT, I DO understand HOW the old Penguins were installed and how to configure the control modules.  SO....LOOK AT THE PRINT.  That is the FIRST THING....

Here goes..  This is how the OLD system worked...and of THAT I AM SURE....100%.  You do NOT have the FOURTH ZONE...or the HIDDEN BRAIN.  So, no need to go looking,

BTW...it took a little research....so if you could have included that, it would have helped.  According to your brochure, you have THREE 15KW Penguins and an AquaHot.  SO....I'm going down that path.  If that is wrong....then you will need to correct me.

When the Blizzards were installed, they MUST BE installed and the units programmed....JUST LIKE THE OLD SYSTEM.  They do NOT come preprogrammed.  The wiring that went into the Control Module MUST BE EXACTLY like the old units. The 15 KW's have all the access on the roof.  

SO, we are on the SAME PAGE... you need to confirm HOW the original system worked.  I downloaded the Blizzard Installation and also printed a PDF of the original HVAC Layout for an AquaHot (Standard) in your Sig.  Look at the Monaco Drawing.  It shows the following....

Front Thermostat  - AC and Furnace worked on it. It was marked or came up as ZONE 1

Rear - You had a Thermostat back there.  The Bedroom (rear AC) was ZONE 1 and the Middle was ZONE 2.

The Front and REAR systems are NOT connected by a Communications Cable.  That is why there is TWO THERMOSTATS.  Thus....the two systems....NEVER TALKED...as they had "No Phone Line"

I also assumed that you have TWO CC2 Thermostats....if only ONE, then somehow or someway, there HAS to be a communications cable running the system....otherwise....they are isolated.

Here is what you need to do first...

In the REAR unit (probably on the roof) there is the control module.  It is explained on page 13 of the install.

The REAR dip switch has ONLY the FURNACE dip switch ON.  NO OTHERS....

The MIDDLE Dip switch has ZONE 2 and FURNACE dip switches ON....NO OTHERS.

That is how the old units were....that is how the new units. work.

NOW....I assume you know how to to a factory reset of the system...Look on page 14.  Read the NOTE or item N.  Since you changed (probably) the DIP switch settings, it is like adding something or changing a peripheral on a PC.. it must be RESET so that the Thermostat identifies the component or any changes in the DIP settings.

OK... reviewed your comment above.  If the AquaHot wires (don't ask me the color) were not connected as they were to the original...they have to be connected.  If you are saying that you can't see a Zone 2 Furnace....then that is a dip switch issue.  When the Furnace dip is ON on any zone, the Thermostat will show the zone.  BUT, if the control wiring....was NOT connected...it ain't gonna work.

Good Luck...let us know...  

 

 

 

installation_manual_64778.pdf 2007 Sig to Dynasty 5 Button AQUAHOT HVAC Layout.pdf

[Tom Cherry]

Gerry, Please click on the QUOTE or just answer in the box below.  Scotty Hutto forwarded this to me....so here is what you said.... I did leave you a VM so call me and we can talk.  I am writing the following for you as well as others, who may be interested, and the fact that you have a custom 2007 with only ONE thermostat and believe that it has FOUR zones....because you were told that....needs addressing...and explaining.

Tom,

 First.  I only have and had from the factory ONE thermostat.  My unit was one of the first coaches that had one thermostat.  This was done when I informed the director or manufacturing that the thermostat would control up to 4 units.  They did not know that so my coach was built with only one thermostat.  All three of the Penguin original units were connected together with the silver statin phone cable.  Everything was working but the furnace in Dometic zones 2 and three with the new Blizzard NXT’s and one CCC2.  Living in southern Nevada I didn’t normally use the furnace but the heat pumps.

Hope that you know have a better understanding of how my coach was built.  It was custom built and has a few things that the standard coaches have.  I spent a lot of time with the plant manager getting things that they normally did not do.  According to the information that I have found with only one CCC2 you need to have a fourth controller as the BRAIN that tells all the others how to deal with the AquaHot and it must be the same controller as the one in each of the roof units.  My problem is that I have NOT been able to locate that fourth controller because it has to be the older version that was compatible with the Penguin units.

I was hoping that someone else on this forum might have a coach built after mine and had found the fourth unit hidden somewhere.  As we all know, Monaco had a habit of making changes and not documenting them very well if at all.

Thanks for your suggestions. 

OK....lets go from there.....  SO HERE GOES.  FIRST...it is easier to TEST the AquaHot in the Diesel mode.  If you have NOT had it serviced, then the Diesel will probably NOT work....and it will take a LONG time for the Electric to get hot.  You did NOT say WHICH mode the AquaHot was in....

FIRST....Did the old system work and did you have the FURNACE MODE for all THREE zones.?

Did you EVER SEE, on the OLD Thermostat, a ZONE 4?  If NOT, then you do NOT have the "brain" or the fourth zone.  IF you DID see a Zone 4 in the old system....then you have the hidden controller.  BUT...FWIW...your AquaHot (assuming again that you got the same one that everyone did, did NOT have a provision for using a Zone 4.  In 2008, Monaco DID add a 4th Zone.  There are ONLY 4 ZONES, per the print, available for your AquaHOT....and the NUMBERS do not match what you see on the Thermostat....fact....and also a major point of confusion for many...  

This may be getting DENSE or DEEP.  But here is how it works....and look at the print.  There are 5 ZONES on the AquaHot.  There is a Thermostat (2 terminals) and a Fan (2 terminals).  When the Thermostat closes (makes a circuit....the BOARD sends a signal, internally, to the corresponding PUMP....and you get water being pumped to a SPECIFIC ZONE....not all over the Motor Home.  There is a specific fan or set of fans for each zone. Those are the FAN terminals.  They provide 12 VDC to the zone's fan(s).  That's HOW IT WORKS.... If you would print out the print...and use a highlighter, you can follow the wires.    

NOW...HERE IS HOW YOUR MH IS WIRED......

Zone 1 on the thermostat....is controlling Zone 5 (YES 5) on the Aquahot

Zone 2 on the thermostat...is controlling Zone 2 on the AquaHot

Zone 3 on the thermostat is controlling Zone 1 on the AquaHot

The BAY HEATER (WET BAY) has a Thermostat.  It is controlling Zone  4 on the AquaHot.

Zone 3 is TOTALLY DISCONNECTED.  You do NOT, to the best of my knowledge even HAVE a Pump #3...

OK....look at your AquaHot.  Pull off the cover.  Look at the board.  If Zone 3 in the middle has NO WIRES....then you do NOT have the "missing or magic" Zone 4....

OK....lets get past that.... 

As a CHECK...QUESTION....did you EVER SEE ZONE 4 on your old  Thermostat?  If the ANSWER is NO....NEVER...then you do NOT have the Hidden Zone 4 Controller.  The 5 Button Thermostat would display up to FOUR ZONES....just like the NEW CC2.  So, if you NEVER used or saw or had a Zone 4....then we can proceed.  If you look at the prints....specifically the Monaco Print....then it STILL has your system....only it is simplified....  In your response....you said that all, AC....assuming that, was working in zones 2 and zones 3.

The Zone 4 that you read about is a STAND ALONE ZONE...with a separate remote temp sensor.  You do NOT, per the AquaHot have that zone.  SO...it doesn't exist as the wiring was not installed...nor was it intended to be that way. Again...pull the cover.  IF you DO have all 5 zones hooked to wires....then no one but a technician who understand the HVAC and AquaHot system can help...and he needs this print and has to mark it up to "AS BUILT".

Back to basics....

Look at the AquaHot control Panel.  If the Red light is ON....clear it with a paper clip.  If it doesn't CLEAR or if you have other trouble lights (read the manual) then that MAY be the problem.

First...  Does Zones 1, 2 & 3 show up on the CC2?  OK...then the DIP Switches for each control unit in the unit (see page 13 of install) is correct.

NEXT....Do you SEE or is there a ZONE 2 and Zone 3 FURNACE mode on the CC2?  If so...then the modules are configured OK.  If you can't FIND or there is NO FURNACE MODE FOR ZONE 2 and ZONE 3...then the controller needs to be configured or programmed properly per the instructions. REMEMBER....if you change a Dip Switch setting...you MUST do the Reset....per the instructions (Section N)

NEXT UP....You can NOT MIX and MATCH AC and Furnace on the Thermostat.  If ONE zone is on AC...then the other two must be...or they can be OFF.  Same for HP....  Same for Furnace.  KEEP ALL THREE ZONES in the same MODE.  OK...if you did that and you can adjust the temperature and are in Zone 2 Furnace...but the AquaHot doesn't work....then...ASSUMING no issues with the AquaHot, you have a WIRING issue in that the TWO Thermostat pair (2 wires per zone) were NOT hooked up properly. 

You CAN test the AquaHot...  With the Panel OFF...use a paper clip (this is DC and not AC), bend a paper clip into a U shape.  Hold it or jumper the AquaHot Zone 2 THERMOSTAT terminals.  The MIDDLE or Zone 2 registers should eventually come on.  You will hear the pump start up.  As LONG as you make the circuit for the Thermostat....it will run.

OK....now test Zone 3...  On the AquaHot, you use the paper clip across Zone 1 Thermostat....and keep it there.  Pump should start....and then it will eventually run. 

That's it.  That explains the system....and what needs to be done 

[Frank McElroy]

On 4/30/2023 at 8:01 PM, Gerry f said:

I have a 2007 Executive Sandia IV

I replaced all three of the Penguin roof A/C Heat pump units with Blizzard NXT's  I also replaced the old thermostat with CCC2.  Everything seemed to work okay until I tried to use the furnace in zones 2 and 3.  Zone 1 in the front and kitchen works great.  They would not come on.  I read that there is a fourth Dometic controller (Brain) that also must be replace to get AquaHot to work properly.  I have been unable to locate this magic fourth controller (Brain).  Does anyone know where Monaco might have hid this unit.  I looked behind the cabinet that is behind the thermostat that is on the back side of the shower and it was not there.

Any help that can be provided would be appreciated.

Thanks,

Gerry Faulkner

2007 Executive Sandia IV 600hp Cummins

Gerry - I sent you an offline reply as a private message.

[Gerry f]

Still trying to locate the “brain” if the system.  It is not in the basement ceiling with the other electronics.  It’s not behind any false walls in any cabinet.  I’m going to start trying to trace the thermo wires that are on the zones if the AquaHot controller this week. 
Will update this posting if I find anything of interest. 
Thanks to everyone that are giving me ideas. 

[Tom Cherry]

5 hours ago, Gerry f said:

Still trying to locate the “brain” if the system.  It is not in the basement ceiling with the other electronics.  It’s not behind any false walls in any cabinet.  I’m going to start trying to trace the thermo wires that are on the zones if the AquaHot controller this week. 
Will update this posting if I find anything of interest. 
Thanks to everyone that are giving me ideas. 

Gerry, after our conversation as well as patching Frank in…..here is the bottom line.

Forget chasing Casper until you determine in he exists.  Here is how youndo that.  Count Remote Sensors.  You may or may not have one up front.  If you have one, it is the gate keeper for the front system….otherwise, the CC2 does that.

Next…REAR bedroom.  Got to be one back there….that is Zone 2.

OK…NOODLE on this.  Your recollection is a bit flaky on Zone 4.  Monaco goofed on Frank’s system.  He DOES have a ZONE 4 controller, but it was not properly labeled.

SCOUR and do a basic search and destroy of the middle.  If you only have ONE remote sensor…PERIOD….in the hallway or center portion….then the ghost never existed.  So there is none.  Memory as well as logic tells me if there is a second remote sensor, it HAS to be in the private bath.  We have helped others that had this hidden issue….and the HVAC/HP sensor for Zone 2 was in the middle or open section.  

If there is not a remote temperature sensor in the private center bathroom, there was never a “brain” (what a dumb name) for Zone 4.  No remote sensor….no input to a Zone 4.  Thats about as simple aa it is….

NEXT UP.  You had LOST the data link between the CC2 and the Zone 2 & 3 units.  Have you restored that?

Good Luck….count noses….

 

[Gerry f]

On 5/15/2023 at 4:23 AM, Tom Cherry said:

Gerry, after our conversation as well as patching Frank in…..here is the bottom line.

Forget chasing Casper until you determine in he exists.  Here is how youndo that.  Count Remote Sensors.  You may or may not have one up front.  If you have one, it is the gate keeper for the front system….otherwise, the CC2 does that.

Next…REAR bedroom.  Got to be one back there….that is Zone 2.

OK…NOODLE on this.  Your recollection is a bit flaky on Zone 4.  Monaco goofed on Frank’s system.  He DOES have a ZONE 4 controller, but it was not properly labeled.

SCOUR and do a basic search and destroy of the middle.  If you only have ONE remote sensor…PERIOD….in the hallway or center portion….then the ghost never existed.  So there is none.  Memory as well as logic tells me if there is a second remote sensor, it HAS to be in the private bath.  We have helped others that had this hidden issue….and the HVAC/HP sensor for Zone 2 was in the middle or open section.  

If there is not a remote temperature sensor in the private center bathroom, there was never a “brain” (what a dumb name) for Zone 4.  No remote sensor….no input to a Zone 4.  Thats about as simple aa it is….

NEXT UP.  You had LOST the data link between the CC2 and the Zone 2 & 3 units.  Have you restored that?

Good Luck….count noses….

 

After weeks of playing hide and go seek for the fathom 4th controller, I finally determined that there was NOT one.  Frank and Tom were right as usual!

With the aid of a DVM, Fluke wire tracer and a oscilloscope I was finally able to find all the problems.  It was a wiring issue.  It seems that Dometic changed the wiring for the furnace controls in the AC control board.  They also changed the wiring of the two black RJ11 communications cables from the control board.  One of the figures in their installation manual shows that the communications cables are straight one to one and in another figure they show that the cables are crossed.

What I discovered is that the RJ11 cables are crossed in both positions in the controller wiring.  I also discovered that Monaco used a coupler for the silver satin communications cables that crossed them again.  With all the communications cables crossing the 12 VDC that powered AC zone 2 and 3 was never getting to the AC control boards and the communications from the thermostat to zones 2 and 3 were never getting to the respective controller boards in the AC units..  After making all the cables pin 1 to pin 1 etc and getting straight through couplers the units all work.  Connecting the proper wires from the AC control board to the correct furnace zone wires now all three systems and furnace zones work properly.

The Nightmare of how this ever worked at all will always be a mystery.  But everything is now working in the HVAC/AquaHot systems as far as the inside heating and AC is concerned.

Thanks again for Frank's and Tom's assistance.  I have certainly learned a lot about how Domectic, AquaHot and Monaco wiring all work together.