Dometic Mother Board

Update: The tstat is cycling the rear AC on and off as needed. Tstat ok. Motherboard ok. AC ok. Bad EMS.

dougrainer wrote:
6300 is the Low Profile Penguin model. THAT model will have the Board ON the AC unit. You have to remove the upper cover of the unit and then remove the Evaporator cover either Styrofoam or plastic, depending on the year of the Penguin. Once the evap cover is removed you will see a 2 by 4 inch metal electrical box in front of the evaporator. THAT houses the 120 from the inside breaker and connects to the 120 going to the Board on the AC unit. This is where you may have a burnt 120 connectiOn IF THE 120 AT THE MAIN BREAKER PANEL SHOWS 120 OUTPUT FROM THE INTELLITEC EMS MODULE. Since you have to go on top and your age, you may have to get either a professional or somebody that is very handy to do the roof top checks. Regardless, you NEED someone that can operate a multitester to check various 120 volt circuits if you are not handy to use one. Doug

Doug, I am parked on the campus of an university and got a chance to have their Heating and Cooling tech look at my problem. There is no 120 present on the output from Intellitec EMS Module. He by-passed the EMS with the 120 and the rear air conditioner powered up and runs great. He did not have the time or proper testing equipment with him to check more. I am able to turn the rear unit on and off by flipping the breaker to allow it to help with the front unit when needed until I can get more info and service. It appears the problem is with the Intellitec EMS or tstat.

Thanks for your help.

It is still raining here. I will check following your instructions when I am more comfortable in doing so. I depended on my RV dealer to save me from climbing on top. They did check on top by removing the cover and testing.

Thanks for your help. I do appreciate it.

6300 is the Low Profile Penguin model. THAT model will have the Board ON the AC unit. You have to remove the upper cover of the unit and then remove the Evaporator cover either Styrofoam or plastic, depending on the year of the Penguin. Once the evap cover is removed you will see a 2 by 4 inch metal electrical box in front of the evaporator. THAT houses the 120 from the inside breaker and connects to the 120 going to the Board on the AC unit. This is where you may have a burnt 120 connectiOn IF THE 120 AT THE MAIN BREAKER PANEL SHOWS 120 OUTPUT FROM THE INTELLITEC EMS MODULE. Since you have to go on top and your age, you may have to get either a professional or somebody that is very handy to do the roof top checks. Regardless, you NEED someone that can operate a multitester to check various 120 volt circuits if you are not handy to use one. Doug

2008 Newmar Grand Star 3752
Intellitec model 900
AC/HP Model 630515. Front and Rear are same. Do not know Series if low or high profile...appears to be low compared to most I see.

This information I gather from inside literature. I am too old, and the weather is too stormy to venture onto the roof.

Do you know if you have the 500 or 600 series Dometic? The 600 is the Penguin models low profile. Doug

This will give you help. Doug

https://intellitec.com/wp-content/uploads/2019/08/53-00894-000.pdf

Have you finally figured out, you have been scammed? You do NOT need the Dometic board, you need the 120 checked at your Main 120 Breaker box. ALL 120 connections for both the Intellitec and the Coach 120 system breakers are in that box. IF the Rear AC output relay has power going out of the Intellitec board, then the odds are the wire nut connections at the rear AC have burned apart, and you have no 120 power to the AC unit. After 43 years as an RV Tech, I have to admit that the current crop of so called RV techs are nothing but part changers. They have no diagnostics skills and just want to replace "Motherboards" as they think all problems are caused by faulty boards. Fur future reference, When I state Year/Brand /Model of RV, please post what I ask for
2008 - Monaco - Diplomat would be what I need. I thank you for knowing that it was the Intellitec system, but there are only 2 REAL systems used Intellitec and PCS. Doug

dougrainer wrote:
I also requested Brand. THAT tells me which EMS system you have. If the EMS does not send the 120 to the rear AC, then nothing on it will run. The tstat controls are 12 volt. Doug

EMS by Intellitec

I also requested Brand. THAT tells me which EMS system you have. If the EMS does not send the 120 to the rear AC, then nothing on it will run. The tstat controls are 12 volt. Doug