Properly turning off your Dometic RV Roof Air Conditioners

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In the past I typically just hit the power button on my Dometic CCC2 thermostat to turn off the air conditioner. I was schooled on this at the recent Balloon Fiesta that the factory actually recommends NOT doing this, I paused, and have to agree. This is the same as pulling the plug on the system. The correct way which I agree with is to press the MODE button and set it to OFF. This will signal to the roof units to turn off but it doesn't just pull the plug on them. I never thought of this and learned something new from a peer (thanks @ARD). 2-1/2 years into this coach ownership and always learning new things. RV peers are amazing and these systems are not the easiest to understand. We learn from each other.
 
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Thanks for the tip Neal. I would assume this would be good practice for the other modes as well. Can’t hurt!
BTW, we seldom boondock and have no added solar. Do you feel that adding soft start to my units would be beneficial and/or worth the effort and expense?
 
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Thanks for the tip Neal. I would assume this would be good practice for the other modes as well. Can’t hurt!
BTW, we seldom boondock and have no added solar. Do you feel that adding soft start to my units would be beneficial and/or worth the effort and expense?
I do as it helps in 30A scenarios. You won’t load shed. Very handy devices. I forgot about them and need to add a thread about it.
 
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In the Mountain Aire on up, the AC/heat pumps are controlled through the SilverLeaf "Climate" panel. The easiest way to turn the AC off is to simply go into the Climate panel and raise the temperature to above ambient. That allows an orderly shutdown of the rooftop units.

If you actually want to turn the AC units off, once they have shut down after the temperature setting has been raised, then you can touch the "COOL" button. The blue backlight will go off and the AC function is then off. Of course, a similar procedure, using the "HEAT" button will turn the heat pump function off.

TJ
 
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Thanks for the tip Neal. I would assume this would be good practice for the other modes as well. Can’t hurt!
BTW, we seldom boondock and have no added solar. Do you feel that adding soft start to my units would be beneficial and/or worth the effort and expense?
Adding "soft start" to virtually any high-draw equipment is beneficial. We've had a large heat pump unit at the sticks-and-bricks for several years. Every time the unit started, the house lights would blink/dim momentarily. A couple years ago, the tech who does our annual service on the unit recommended adding the soft-start function. We agreed and have never had a light blink since. And, the cost was pretty minimal.

TJ
 
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Education needed! What does "soft start" mean & what does it actually do? Maybe gradually increase the current flow at start up?
What are the benefits, other than what TJ just mentioned?:unsure:
 
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Here is the link to it, I have it on both of my AC's.


@Chuggs is Mr. Electrical and can probably explain it best, certainly not me. But I've been impressed as my generator doesn't even load up when the AC comes on like it did prior to using them.
 
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To keep it in easy-to-understand language, soft-start eases your ACs (or other high-amperage equipment) into the starting cycle rather than having the full draw hit all at once.

In a sense, you can think of it this way: if you want to pull something heavy with a pickup truck and a chain, you hook up and there will be some slack in the chain. Now, without soft-start it would be like dropping the pickup into gear and slamming the gas to the floor. Big bang when the slack is gone and lots or stress and strain on the truck, chain and you! Or, you can ease into the throttle while the chain slowly tightens and once it is tight, you can then apply full power. No banging and bumping with the more gentle application of power.

I'm no electrical engineer, so that's the best I can do.

TJ
 
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TJ.....Great explanation! As an old "car guy", I can relate!
Thanks
 
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Even if you do just kill the power you really aren't doing any damage to your unit. When your thermostat shuts the system down (reaches temp) the power to the compressor is shut off just like hitting a switch and the same for when the blower motor shuts down. The only difference is they don't shut down together. A couple of advantages to shutting the blower down after the compressor is you gain a slight bit of additional cooling while the pressures equalize. You can also start the compressor sooner since the pressures are equalized quicker.
 
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