“No Controller Detected” 2023 Coachmen Prism Elite

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I have seen previous posts from a couple years back, discussing the communication issue between the Firefly control panel, and a GE HVAC. It seemed that GE was aware they had an issue and had a firmware fix for existing units, and the problem would be resolved on new units. We bought our 2023 Coachmen Prism Elite September 1, 2024. We are the original owners. Pretty much from the jump, our HVAC has had a recurring issue with the “No Controller Detected” error on the Firefly display, and the HVAC unit becoming unresponsive. I contacted Forrest River, who in turn put me in touch with a rep from Firefly. We ran through a diagnostic session both behind the Firefly panel, and at the connector, from the Firefly wire into the HVAC control box. It was determined that the Firefly was functioning properly through the use of a multimeter, and therefore the problem was the GE control box. Forrest River was very engaged in trying to resolve the issue, and promptly sent me a replacement control box. The original GE control box was model number RAREC1A4. The replacement control box was model number RAREC1A5. The replacement seemed to fix the issue initially, but unfortunately the problem is now ongoing. The HVAC unit works for a time, then stops cutting itself off when appropriate, and leads to the recurring message “No Controller Detected”, at which point the unit is completely unresponsive. I have been guided through the settings on the Firefly, to confirm that the correct HVAC unit has been selected on my floor plan, which it has. To me, this sounds like the problem GE previously thought they had solved, has in fact not been solved. I am going to attach photos of the issue. Any suggestions would be very much appreciated. Needless to say, living in the southeast, no AC has kept us from really ever getting started on our RV adventures. We bought the RV from a dealership in the upper Midwest, so it isn’t a “run it to the dealer” issue. The dealership has been very helpful as far as putting us in contact with an individual at Forrest River who has been very timely in our communications, but now I understand why one of Forrest River’s catch phrases is “Buy Local.” They are 100% right about that. Thanks in advance for any suggestions!!
Bob

 

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Perhaps I have a diagnosis.

So this morning, out of the blue, the fan on the unit started trying to kick on, but couldn’t quite make it. It repeatedly tried to come on for a couple of seconds, but paused, then tried again. The “No Controller Detected” error message was gone. The Firefly was set to “auto temp and auto fan”. While it was trying to start, a clicking sound could be heard in the area of the GE control box. I suspect there is a bad relay on the board. I turned the main breaker off, then on again, and the heat pump came on and stayed on. The clicking sound was gone. When I say “stayed on”… I meant stayed on. It went nine degrees past where the Firefly was set (when this started it was 65 in the Coach, and the temp was set to 71), and wouldn’t turn off. It required turning the main breaker off to get it to stop running, but when you turned the breaker back on, the heat pump started up again. The temp is set to 71, but it went to 80 degrees in the Coach. When it got to 80 degrees, the unit switched over to AC, and started trying to cool the coach back down. If the trend repeats itself, the “No Controller Found” will reappear, and the unit will become completely unresponsive again. Does this sound like a bad relay on the GE control board? Thanks again in advance for any help.
Bob

 

[Aussieguy]

try disconnecting all power shorepower battery and solar

see if your System will reboot

no controller on HVAC >.. wonder if that means the thermostat?


Just a thought since I don't have a firefly

 

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It is puzzling. The thermostat is part of the Firefly, but there is a sensor on the side of a cabinet next to the slide. It is almost at ceiling level… you would think they would place it more towards the middle of the height of the Coach. The current situation is that I have to turn the breaker to the HVAC off, to make it shutdown. When the breaker is turned back on, it fires right back up. I also have learned that there is a “constant on” wire leading to the Firefly main board (which is behind the panel the Firefly is mounted to), that you have to unplug, even when you cut shore power and the cabin 12v off, to try to do the reset you have mentioned. I have done that as well. I have had plenty of luck, unfortunately it has all been bad.

 

[Aussieguy]

disconnect the NEGATIVE battery and any solar cables to force reboot

 

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Today I:
*Disconnected Shore Power
*Turned off Coach power
*Disconnected negative battery cables on the Coach
* I do not yet have solar panels.

I let it remain in this (as far as I know) unpowered state for 30 minutes. I reconnected all of the above, in the reverse order they were disconnected. Unfortunately, when it powered back up, the “no controller detected” warning persisted, and the HVAC was completely unresponsive. Everything else in the Coach works perfectly, to include the separate LP furnace, which is fortunate, as cold weather has arrived. I am going to contact the gentleman who has been helping me at Forrest River, and see if he thinks I need a new HVAC control box again. The clicking when it was trying to turn on in the recent past, still sounds like a bad relay on the GE control box.
I appreciate your response. I was hoping that disconnecting the battery bank ground would cause it to “find” the GE HVAC since I had not previously done that, but unfortunately it did not.

 

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It is now Feb 21, 2025 and this situation still persists. We took it to a FR dealership, and they noticed there had been a service bulletin, which stated a “jumper” needed to be placed on two specific pins on the FireFly control panel. The dealership did not have any. I contacted the gentleman at FR, and he sent one directly to me, and I scheduled another appointment at the dealership for installation. The jumper was installed, the system reset, and still the same issue. They contacted FireFly who did the same diagnostic walkthrough as they did with me in an above post, and again determined that their unit was functioning properly, and the GE HVAC control box needed to be replaced once again. They have ordered a new control box, and we are awaiting its arrival and installation. Having already replaced the control box once, I reasonably (to me anyway) question if we will have a different (positive) outcome. At some point, this could become frustrating. /sarc. I will say the dealership has seemed very responsive and committed to solving this for us, as has FR, but still no solution.