The manuals provided with my Berk are very sketchy in telling me how to use the AGS.
• The overall RV manual from Forest River doesn’t mention AGS at all.
• My RV came with a Magnum ME-RC remote control and a manual, which is also at http://www.magnum-dimensions.com/sit...-ME-RC_Web.pdf
• I had to download the documentation for the Auto Gen Start Network module (AGS-N) module that came with my RV: ME-AGS-N Owner's Manual | 64-0039 Rev B | Magnum Dimensions
• There is also an AGS-N Spec sheet at http://www.magnum-dimensions.com/sit...sheet_revc.pdf
• I had lengthy email discussions with the Magnum/Sensata tech department, representatives at the Forest River Diesel Division.
I have also had the local Magnum service rep swap in a new AGS-N unit and it performed the same as the one shipped with my RV.
My AGS-N came with a Remote Temperature Sensor Cable as per Section 2.4.1 of the AGS-N manual. The Forest River rep says that it is connected to a temperature sensor in the bedroom air conditioner. I assumed that the temperature sensor for the bedroom A/C is on the bedroom wall next to the bathroom, in a little round black button, but I may be wrong. It could be in the A/C unit.
Section 7.0 of the ME-RC model describes how to set up the run time and start conditions for the generator. It discusses two methods for starting the generator to run the A/C: either use a temperature setting on the AGS: -4 Start Temp F Menu, or an optional ME-PT1 or ME-PT2 pigtail adaptor. I don’t have the pigtail adaptor, so I will discuss it in a later post. I have set the run time to the shortest allowed: 0.5 hours
This leaves me to run the generator on the basis of the temperature read by the sensor wire. The big question is how to set this temperature relative to the temperature set in the A/C thermostat (a Dometic CCC 2 in my case). In a paragraph in Section 7.0 entitled “Where should I set Start Temp?” it says:
“the AGS: 04 Start Temp F setting should be slightly above the A/C unit’s thermostat “cool” temperature (usually around 70-72F). Once the temperature setting is reached, the generator will start providing power to the A/C unit. The reason the temperature is set above the A/C unit’s thermostat is to ensure the A/C unit will run when the generator starts.”
When I do that, the A/C attempts to start from the Magnum ME2012 inverter before the generator is on. Although the inverter claims to be able to produce 3100 watts of power for 5 minutes, it doesn’t have enough power to run the A/C. The A/C doesn’t run and gives an E7 fault code in the Dometic CCC LCD panel.
Perhaps this would work if I had a bigger set of batteries than the 4 golf cart batteries that I have. But, I’m not sure if the battery bay will handle the weight of bigger batteries, such as L16s that would weigh 500 lb vs 250 lbs for the golf cart batteries.
When I discussed this by email with Mike Bukowski at Forest River, he said that I need to set the temperature on the A/C to start after the generator starts, so it should be slightly lower than the temperature set for the A/C. This is opposite to the Magnum recommendation. There are three problems with this approach:
1. The ME-RC unit only allows 5 degree steps in the the temperature threshold, which is pretty coarse. For example, I could set the ME-RC to start at 75 degrees F, and the A/C to start at 76 F. But, I couldn’t get the AC to start at 73 F.
2. The generator could run for a very long time before the room temperature rises the extra degree to start the A/C. This is a waste of fuel.
3. On the downside, the A/C won’t get the room temperature low enough to auto-stop the generator when cooling is no longer needed. This is because the generator needs a temperature one degree lower to auto stop. Again, this is a waste of fuel.
As a positive note, I must say that if I am just auto-starting the generator based on temperature or voltage, and if I remove the temperature or voltage requirement in the ME-RC, then the generator does successfully auto-stop if it has run for my preset time of 0.5 hours.
I’d be very interested to hear if others successfully use this procedure “by the book” or some variation of it. And, does it auto-stop the generator when the A/C comes off?